Title of Invention	NITROGEN-CONTAINING HETEROCYCLIC DERIVATIVES.
Abstract	The invention provides a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof, and a pharmaceutical composition comprising the nitrogen-containing heterocyclic derivative and a pharmaceutically acceptable salt thereof, in particular, a pharmaceutical composition effective as a sodium channel inhibitor, having an excellent analgesic action especially on neuropathic pain with minimized side effects.

Title of Invention

NITROGEN-CONTAINING HETEROCYCLIC DERIVATIVES.

Abstract

The invention provides a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof, and a pharmaceutical composition comprising the nitrogen-containing heterocyclic derivative and a pharmaceutically acceptable salt thereof, in particular, a pharmaceutical composition effective as a sodium channel inhibitor, having an excellent analgesic action especially on neuropathic pain with minimized side effects.

Full Text	TECHNICAL FIELD The present invention relates to a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof. The present invention further relates to a pharmaceutical composition comprising a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof and more particularly, to a pharmaceutical composition having an analgesic action especially on neuropathic pain which acts as a sodium channel inhibitor. BACKGROUND ART A voltage-dependent sodium channel is a protein responsible for the initiation and propagation of action potentials in neurons. The voltage-dependent sodium channel is composed of one larger a subunit with four domains, each consisting of six transmembrane segments, as a common structure and two smaller P subunits. A maIor part of the channel function is played by a subunit. To date, more than 10 different a subunit subtypes have been known(Goldin AL, Annals of the New York Academy of Sciences 868:38-50, 1999). Each voltage-dependent sodium channel subtype shows distinct distributions in the central and peripheral nerve tissues. These subtypes regulate neural excitability and play an important role in regulating physiological functions in individual tissues. It is also suggested that they are deeply associated with various pathological conditions (Goldin AL, Annual Review of Physiology 63:871-894, 2001). In recent years, it has become clear that voltage-dependent sodium channels are deeply involved in neural transmission of pain, and sodium channel blockers are expected to be excellent pain therapeutics, especially neuropathic pain therapeutics (Taylor CP, Current Pharmaceutical Design 2: 375-388, 1996). Neuropathic pain means a pain that results from dysfunction in the central or peripheral neurons and refers to diabetic neuropathic pain, cancer pain, trigeminal neuralgia, phantom limb, post herpetic neuralgia, thalamic pain, etc. The clinical picture of neuropathic pain includes stabbing pain, burning pain, hyperalgesia, allodynia, etc. In medical scenes, non-steroidal anti-inflammatory drugs, narcotic analgesics such as morphine, etc. are used for the purpose of relieving pain. Recently, antiarrhythmic drugs and anticonvulsants, which are sodium channel blockers, have come to be used as well, for the purpose of relieving pain. The non-steroidal anti-inflammatory drugs are not completely satisfied in terms of analgesic actions and involve the problem of side effects such as gastrointestinal disturbance or renal disorder. The narcotic analgesics such as morphine are effective for nociceptive pain, but encounter serious side effects on the alimentary, respiratory or central nervous system. In addition, these drugs are generally less effective for neuropathic pain. The antiarrhythmic drugs such as lidocaine or mexiletine and the anticonvulsants such as carbamazepine, which are sodium channel blockers, have come to be used to relieve pain. Mexiletine has been approved and is available as an anti-diabetic neuropathic pain drug. However, these sodium channel blockers involve problems that they have central side effects such as convulsions or drowsiness, or peripheral side effects such as bradycardia and hence, have difficulty to increase a dose to a sufficient level, resulting in failure to achieve satisfactory analgesic effects. As above, analgesics that are useful for the treatment of neuropathic pain and are excellent in safety have not been found yet. Accordingly, sodium channel blockers having an excellent analgesic action especially on neuropathic pain with minimized side effects have been desired. Lidocaine, mexiletine, carbamazepine, etc. mentioned above are reported but do not fall under nitrogen-containing heterocyclic derivatives having styryl group. Derivatives having a 1-pyridylalkylpiperidine as a basic skeleton are disclosed and have a sodium channel inhibitory activity (Patent Literature 1). In this literature, compounds having 2-cyclohexylmethyloxy-6-fluorophenylethenyl on the piperidine ring as a substituent are disclosed. Also, compounds containing a mono-substituted phenylethenyl having a halogen or cyclohexylmethyloxy at the 2- or 3-position of a 1-aromatic heterocyclic group-alkylpiperidine ring as a substituent are described (Patent Literature 2). On the other hand, compounds, not as sodium inhibitors but as metabotropic glutamate receptor (mGluR) inhibitors and analgesics, which are one of therapeutics for various diseases, based on mGluR inhibitory effects are disclosed (Patent Literatures 3 - 4). Specifically, there are described 2-pyridine compounds having styryl group (Patent Literature 3), thiazole, oxazole, 1,2,4-thiadiazole, 1,2,4-oxadiazole, lH-l,2,4-triazole, 2-oxo-l,3,4-oxathiazole, 2H-tetrazole, 2-pyridine, pyridinium, pirazine, indolinium, benzothiophene, benzothiazonium, quinoline or quinolium compounds having styryl group (Patent Literature 4), imidazole compounds having styryl group (Patent Literature 5), and imidazole, 1.2,4-triazole or 2H-tetrazole compounds having styryl group (Patent Literature 6), but these compounds are unsaturated heterocyclic compounds having styryl group. Furthermore, piperidine compounds having benzyl or phenylmethylene based on NMDA/NR2B antagonizing effect are disclosed (Patent Literature 7). On the other hand, nitrogen-containing heterocyclic derivatives having styryl group, which are formed by combining groups, are disclosed (Patent Literatures 8 and 9) and among these derivatives, only the compounds that phenyl group and a nitrogen-containing heterocyclic ring are combined via a -O-lower alkylene-(Patent Literature 3), a -S-lower alkylene- or a -lower alkylene-C(0)0- are specifically disclosed (Patent Literature 4) but nitrogen-containing heterocyclic derivatives are neither disclosed specifically nor even suggested. Moreover, these derivatives are used as calcium channel antagonists (Patent Literature 8) or for promotion of acetylcholine release (Patent Literature 9) but nothing is disclosed or even suggested on any sodium channel inhibitory activity or any analgesic action. Patent Literature 1 European Patent Publication No. 1254904 Patent Literature 2 WO03/84948 Pamphlet Patent Literature 3 WO99/02497 Pamphlet Patent Literature 4 WO01/16121 Pamphlet Patent Literature 5 WO02/46166 Pamphlet Patent Literature 6 WO99/08678 Pamphlet Patent Literature 7 WOO 1/32615 Pamphlet Patent Litera+ture 8 W094/13291 Pamphlet Patent Literature 9 W097/19059 Pamphlet DISCLOSURE OF THE INVENTION An obIect of the present invention is to provide a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl or a pharmaceutically acceptable salt thereof. Another obIect of the present invention is to provide a pharmaceutical composition, especially a pharmaceutical composition for a sodium channel inhibitor, which has a remarkable analgesic action on neuropathic pain, comprising the nitrogen-containing heterocyclic derivatives having 2,6-disubstituted styryl or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier. The present inventors made extensive studies on nitrogen-containing heterocyclic derivatives to achieve the foregoing obIects and as a result, have found that derivatives containing a nitrogen-containing hetero ring having 2,6-disubstituted styryl as a basic skeleton or salts thereof possess a potent inhibitory activity against sodium channel and exert an action on mice with streptozotocin-induced diabetic neuropathy as disease animal models, and have accomplished the present invention, which is useful for neuropathic pain drugs. That is, the present invention relates to the nitrogen-containing heterocyclic derivatives represented by formula (I) below. The nitrogen-containing heterocyclic derivatives of the present invention are characterized in comprising styryl group always having two substituents at the ortho-position, namely, 2,6-disubstituted styryl group, and a nitrogen-containing heterocyclic group. This styryl group may optionally have an additional substituent(s). In the nitrogen-containing heterocyclic derivatives, saturated nitrogen-containing heterocyclic derivatives are preferred. Specifically, the present invention provides the following nitrogen-containing heterocyclic derivatives or pharmaceutically acceptable salts thereof, pharmaceutical compositions comprising these compounds and pharmaceutically acceptable carriers, use of these compounds, a method for treating diseases mediated by sodium channel, a method for treating neuropathic pain, and a method for treating diabetic neuropathic pain. [l A nitrogen-containing heterocyclic derivative represented by formula (I) 5 (wherein symbols in formula (I) above have the following significance: R1 and R2, which may be the same or different, represent H-, an optionally substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower alkyl-O-CO-, HaN-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an aryl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a 10 halogen, nitro, a heterocyclic group, or cyano; R3 and R4, which may be the same or different, represent an optionally substituted lower alkyl, a cycloalkyl, an acyl, HO-CO-, a lower alkyl-O-CO-, H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a halogen, nitro, 15 or cyano; R5 and R6, which may be the same or different, represent H-, a lower alkyl, or a halogen; R7 and R8, which may be the same or different, represent H-, a lower alkyl, HO- a lower alkyl-O-, or a halogen; 2Q R7 and R8 may be combined together to form oxo (0=); R9 represents H-, an optionally substituted lower alkyl, an optionally substituted cycloalkyl, an optionally substituted acyl, a lower alkyl-C (=NH)-, HO-CO-, an optionally substituted lower alkyl-O-CO-, H2N-CO-, an optionally substituted lower alkyl-HN-CO-, an (optionally substituted lower alkyl)2N-CO-, 25 H2NC(=NH)-, H2NC(=NCN)-, H2NC(=N-CONH2), H2NC(=NS(=0)2NH2)-, an optionally substituted lower alkyl-S02- or an optionally substituted heterocyclic group-S02-; R10, R11, R12 and R13, which may be the same or different, represent H-, or a lower alkyl, and two groups from R10, R11, R12 and R13 may be combined together to 30 form oxo (0=); A represents a nitrogen-containing heterocyclic group, quinolyl or pyrtdin-4-yl; provided that when A represents quinolyl or pyridin-4-yl, R9 is absent; and, n represents 0, 1, or 2), or a pharmaceutically acceptable salt thereof. 12] The nitrogen-containing heterocyclic derivative according to [1], or a pharmaceutically acceptable salt thereof, wherein the nitrogen-containing heterocyclic group shown by symbol A in the formula (I) is a nitrogen-containing saturated monocyclic heterocyclic group or a nitrogen-containing saturated bridged ring. 13] The nitrogen-containing heterocyclic derivative according to [2], or a pharmaceutically acceptable salt thereof, wherein the nitrogen-containing heterocyclic group shown by symbol A in the formula (I) is a nitrogen-containing saturated monocyclic heterocyclic group. [4] The nitrogen-containing heterocyclic derivative according to [3], or a pharmaceutically acceptable salt thereof, wherein the nitrogen-containing heterocyclic group shown by symbol A in the formula (I) is a 6-membered nitrogen- containing saturated monocyclic heterocyclic group. In the nitrogen-containing heterocyclic derivatives or pharmaceutically acceptable salts thereof according to [1] to [4], preferably the nitrogen-containing saturated heterocyclic group shown by symbol A in the formula (I) is piperidine. [5] The nitrogen-containing heterocyclic derivative according to any one of [1] through [4], or a pharmaceutically acceptable salt thereof, wherein symbols R7 and R8 in the formula (I) above, which may be the same or different, represent H-, a lower alkyl, HO-, a lower alkyl-O-, or a halogen. [6] The nitrogen-containing heterocyclic derivative according to any one of [1] through [5], or a pharmaceutically acceptable salt thereof, wherein symbol n in the formula (I) is 0. [7] The nitrogen-containing heterocyclic derivative according to any one of [1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (I) is H. 18] The nitrogen-containing heterocyclic derivative according to any one of [1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (I) is an optionally substituted lower alkyl. 19] The nitrogen-containing heterocyclic derivative according to [8], or a pharmaceutically acceptable salt thereof, wherein the substituent in the optionally substituted lower alkyl shown by symbol R9 in the formula (I) is at least one substituent selected from Group a below: Group a: (1) a halogen, (2) HO, (3) a lower alkyl-O-, (4) H2N, (5) a lower alkyl-NH-. (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group; this heterocyclic group is preferably a monocyclic heterocyclic group. [10] The nitrogen-containing heterocyclic derivative according to any one of [1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (I) is an optionally substituted acyl. [11] The nitrogen-containing heterocyclic derivative according to [10], or a pharmaceutically acceptable salt thereof, wherein the optionally substituted acyl shown by symbol R9 in the formula (I) is an optionally substituted lower alkyl-CO-, an optionally substituted cycloalkyl-CO-, an optionally substituted aryl-CO-, an optionally substituted heterocyclic group-CO- or an optionally substituted heterocyclic group-lower alkyl-CO-. [1.2] The nitrogen-containing heterocyclic derivative according to [10] or [11], or a pharmaceutically acceptable salt thereof, wherein the substituent in the optionally substituted acyl shown by symbol R9 in the formula (I) is at least one substituent selected from Group b below: Group b: (1) HO, (2) a lower alkyl-O-, (3) R101R102N (wherein R101 and R102, which may be the same or different, represent (i) H, (ii) a lower alkyl which may optionally be substituted with HO, a lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a lower alkyl-NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower alkyl)2N-, (iii) an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an aryl which may optionally be substituted with a halogen), (4) a halogen, (5) oxo (0=), (6)a cycloalkyl which may be optionally substituted with R101R102N, (7) an aryl, (8)a heterocyclic group, (9) a lower alkyl which may optionally be substituted with HO, a lower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which may optionally be substituted with oxo (0=), (ll)H2N-CO-, (12) a lower alkyl-S02-, and Q 3) a heterocyclic group-S02-. [13] The nitrogen-containing heterocyclic derivative according to any one of [1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (I) is HO-OC-, an optionally substituted lower alkyl-O-CO-, H2N-CO-, an optionally substituted lower alkyl-NH-CO-, an (optionally substituted lower alkyl)2N-CO- or an optionally substituted lower alkyl-S02-. In the nitrogen-containing heterocyclic derivatives or pharmaceutically acceptable salts thereof according to any one of [1] through [13], symbols R4 and R5 in the formula (I) above are more preferably a lower alkyl, and most preferably, these R4 and R5 are methyl group. [4] The nitrogen-containing heterocyclic derivative according to [1], or a pharmaceutically acceptable salt thereof, which is at least one compound selected from the group consisting of: 4-[(E)-2-(2,6-dimethylphenyl)vinyl]quinuclidine, 4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine, 4-[(Z)-2-(2,6-dimethylphenyl)vinyl]piperidine, 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine, 3,5-dimethyl-4-[(E)-2-piperidin-4-ylvinyl]benzonitrile, N,N,3,5-tetramethyl-4-[(E)-2-piperidin-4-ylvinyl]aniline, 2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine, 4-[(E)-2-(2,6-dimethylphenyl)vinyl]azepane, 4-[(2E)-3-(2,6-dimethylphenyl)prop-2-en-l-yl]piperidine, 3 -[(E)-2- (2,6-dimethylphenyl)vinyl]-1 -methylpiperidine, l-benzyl-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine, (2-{4-[(Ii)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}ethyl)dimethylamine, 5-({4-[0i)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}carbonyl)-lH-l,2,4-triazol-3- amine, 4-(2-{4-[(E)-2-(2,6-dimethyl-4-phenoxyphenyl)vinyl]piperidin-l-yl}-2-oxoethyl) morpholine, 4-(2-{2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine, l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-4-(pyridin-3- ylcarbonyl)piperazine, (2- {4-[(E)-2-(2,6-dimethylphenyl)viny l]piperidin-1 -yl} -1,1 -dimethyl-2-oxoethyl) amine, [ 1 -({4-\| (E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} carbonyl)cy clobutyl] amine, 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-[(2S)-pyrolidin-2-ylcarbonyl]piperidine, 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(lH-imidazol-1 -ylacetyl)piperidine, N-(2- { 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)oxetane-3 - amine, N-{2-[(2-[4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl]-2-oxoethyl)amino] ethyl} acetamide, 2-[(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)amino]ethanol, 1 -(2- {4-[(E)-2-(2,6-dimethy lphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)piperidine- 2-carboxamide, l-(2-{4-(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-3,5-dimethyl piperidine, 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-[(4-pyrolidin-l-ylpiperidin-l-yl)acetyl] piperidine, 4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine, [4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine-2- yl] methanol, 4-(2- {4- [(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)-1,4-oxazepane, l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)piperidine-4- amine, 1 -(2- {4- [ (E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)piperazine, (lR,4R)-2-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-2,5- diazabicyclo[2.2.1]heptane, and, (2-{4-[(E)-2-(2I6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)methyl[(3R)- tetrahyd rofuran-3 -yl] amine. [15] A pharmaceutical composition comprising the nitrogen-containing heterocyclic derivative according to any one of [1] through [14], or a pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier. [16] The pharmaceutical composition according to [15], which is a sodium channel inhibitor. [17] The pharmaceutical composition according to [15] or [16], which is a therapeutic agent for neuropathic pain. [18] The pharmaceutical composition according to [17], which is a therapeutic agent for diabetic neuropathic pain. [19] Use of the nitrogen-containing heterocyclic derivative according to any one of [1] through [14], or a pharmaceutically acceptable salt thereof, to manufacture a pharmaceutical composition. [20] Use of the nitrogen-containing heterocyclic derivative according to [19], or a pharmaceutically acceptable salt thereof, to manufacture a therapeutic agent for neuropathic pain. [21] Use of the nitrogen-containing heterocyclic derivative according to [20], or a pharmaceutically acceptable salt thereof, to manufacture a therapeutic agent for diabetic neuropathic pain. [22] A method for treating a disease caused by sodium channel, which comprises administering to a patient a therapeutically effective dose of the nitrogen-containing heterocyclic derivative according to any one of [1] through [12], or a pharmaceutically acceptable salt thereof. [23] A method for treating neuropathic pain, which comprises administering to a patient a therapeutically effective dose of the nitrogen-containing heterocyclic derivative according to [22], or a pharmaceutically acceptable salt thereof. [24] A method for treating diabetic neuropathic pain, which comprises administering to a patient a therapeutically effective dose of the nitrogen-containing heterocyclic derivative according to [23], or a pharmaceutically acceptable salt thereof. BEST MODE FOR CARRYING OUT THE INVENTION The compounds of the present invention represented by formula (I) (hereinafter sometimes merely referred to as "Compound (I) of the present invention") will be described below in detail. [Definition, etc.] In the definitions of the structural formulae in the specification, the term "lower" is used to mean a straight or branched carbon chain having the carbon number of 1 to 6, unless otherwise indicated. Examples of The "lower alkyl", for example, is used to mean methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, isohexyl, and the like, preferably, methyl, ethyl, propyl, butyl and tert-butyl The "lower alkenyl" is used to mean a hydrocarbon group having at least one double bond and includes, for example, vinyl, propenyl, allyl, isopropenyl, hexenyl, and the like. The "lower alkynyl" is used to mean a hydrocarbon group having at least one triple bond and includes, for example, ethynyl, propynyl, butynyl, and the like. The "cycloalkyl" is used to mean a 1- to 3-ring aliphatic saturated hydrocarbon group having the carbon number of 3 to 14 and includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, bicycloheptyl, bicyclooctyl, bicyclononyl, bicyclodecanyl, tricyclononyl, tricyclodecanyl, tricycloundecanyl, tricyclododecanyl, bicyclo[2.2.1]heptyl, bicyclo[2 2.2]octyl, and the like, preferably, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl. The "aryl" is used to mean a 1- to 3-ring aromatic hydrocarbon group having the carbon number of 6 to 14, in which a cycloalkyl may optionally be fused to a phenyl. The aryl includes, for example, phenyl, indenyl, naphthyl, anthryl, phenanthryl, indanyl, tetrahydronaphthyl, and the like, preferably, phenyl and naphthyl. The "heterocyclic group" is used to mean a 4- to 16-membered monocyclic, bicyclic or tricyclic saturated or unsaturated ring containing 1 to 4 hetero atoms selected from N, S and O. This heterocyclic group may optionally be bridged or may optionally take a spiro form. The unsaturated ring includes an aromatic ring (hetero aryl) and a non-aromatic ring. The monocyclic group includes azetidinyl, oxetanyl, pyrrolidinyl, tetrahydrofuranyl, 1,3-dioxoranyl, tetrahydro-2H-pyranyl, pyrazolidinyl, piperazinyl, piperidinyl, morpholinyl, thiomorpholinyl, 1,4-oxazepanyl, trithianyl, dioxoranyl, furyl, thienyl, pyrrolyl, 2,5-dihydro-lH-pyrrol-l-yl, imidazolyl, pyrazolyl, thiazolyl, oxazolyl, pyridyl, pirazinyl, pyrimidyl, triazolyl, thiadiazolyl, pyridazinyl, triazinyl, tetrahydropyranyl, oxadiazolyl, and the like; the bicyclic group includes indolinyl, isoindolinyl, 3, 4-methylenedioxyphenyl, 3, 4-ethylenedioxyphenyl, benzofuranyl, benzothienyl, benzothiadiazolyl, benzothiazolyl, benzimidazolyl, indolyl, 2,3-dihydroindolyl, quinolyl, isoquinolyl, 1,2,3,4-tetrahydroquinolyl, decahydroquinolyl, 1,2,3,4-tetrahydroisoquinolyl, decahydroisoquinolyl, quinoxalinyl, and the like; and the tricyclic group includes carbazolyl, acridinyl, phenothiadinyl, and the like. The bridged heterocyclic group includes quinuclidinyl, 2,5-diazabicyclo[2.2.1]heptyl, 8-azabicyclo[3.2.1]octyl, 7-azabicyclo[2.2. l]heptyl, and the like. The spiro-heterocyclic group includes l,4-dioxa-8-azaspiro[4.5]decanyl, and the like. The "nitrogen-containing hetero-aryl" is used to mean a 4- to 10-membered mono- or bicyclic nitrogen-containing hetero-aryl having 1 to 3 nitrogen atoms in the heterocyclic groups described above and includes, for example, pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, pyridyl, pyridazyl, pyrimidyl, pyrazyl, triazyl, indolyl, isoindolyl, benzimidazolyl, benzopyrazolyl, pyrrolopyridyl, imidazopyridyl, quinolyl, isoquinolyl, quinoxalyl, and the like, preferably, imidazolyl, pyridyl and quinolyl. The "nitrogen-containing saturated heterocyclic group " is used to mean a 3- to 10-membered mono- or bicyclic nitrogen-containing heterocycloalkyl having 1 to 3 nitrogen atoms in the heterocyclic groups described above and includes, for example, aziridinyl, azetidinyl, pyrrolidyl, piperidyl, piperazyl, morpholinyl, hexahydroazepinyl, 1,4-diazepinyl, 1,4-oxazepinyl, quinuclidinyl, 2,5-diazabicyclo[2.2.1]heptane, azabicyclooctyl (e.g., azabicyclo[3.2.1]octyl), diazabicyclooctyl, azabicyclononyl, azabicyclodecanyl, l,4-dioxa-8-azaspiro[4.5]decanyl, and the like, preferably, pyrrolidyl, piperidyl, piperazyl, morpholinyl, hexahydroazepinyl, 1,4-diazepinyl, 1,4-oxazepinyl, quinuclidinyl, 2,5-diazabicyclo[2.2.1]heptane and azabicyclo[3.2.1]octyl. The "nitrogen-containing heterocyclic group" is used to mean the nitrogen-containing hetero-aryl described above, the nitrogen-containing saturated heterocyclic group described above, or a group formed by fusing the nitrogen-containing heterocyclic group or the nitrogen-containing hetero-aryl and the nitrogen-containing heterocycloalkyl, and preferably means pyrrolidyl, piperidyl, morpholinyl, hexahydroazepinyl, azabicyclo[3.2.1]octyl, l,4-dioxa-8-azaspiro[4.5]decanyl, imidazolyl, pyridyl and quinolyl. The "acyl" includes HCO-, a lower alkyl-CO-, a lower alkenyl-CO-, a cycloalkyl-CO-, aryl-CO-, a heterocyclic group-CO-, a heterocyclic group-lower alkyl-CO-, a heterocyclic group-lower alkenyl-CO-, a heterocyclic group-lower alkynyl-CO-, a lower alkyl-CS-, a lower alkenyl-CS-, a cycloalkyl-CS-, an aryl-CS-, heterocyclic group-CS-, a heterocyclic group-lower alkyl-CS-, a heterocyclic group-lower alkenyl-CS- and a heterocyclic group-lower alkynyl-CS-. Preferably, the acyl is a lower alkyl-CO-, a cycloalkyl-CO-, an aryl-CO-, a heterocyclic group-CO- and a heterocyclic group-lower alkyl-CO-. This heterocyclic group-CO- is more preferably a monocyclic heterocyclic group-CO-. Specific examples are HCO-, acetyl, propionyl, cyclopropylcarbonyl, cyclobutylcarbonyl, cyclopentylcarbonyl, cyclohexylcarbonyl, azetidin-2-ylcarbonyl, 2,5-dihydro-lH-pyrrol-l-ylmethylcarbonyl, pyrolidin-2-ylcarbonyl, pyrolidin-1 -ylmethylcarbonyl, piperidin-2-ylcarbonyl, piperidin-3-ylcarbonyl, piperidm-4-ylcarbonyl, morphoIin-2-ylcarbonyl, morpholin-3-ylcarbonyl, morpholin-4-ylmethylcarbonyl, 1,4-oxazepan-4-yl-carbonyl, l,4-oxazepan-4-yl-methylcarbonyl, piperidin-1-ylmethylcarbonyl, benzoyl, imidazol-4-ylcarbonyl, imidazol-1 -ylmethylcarbonyl, l,2,4-triazol-2-ylcarbonyl, pyridin-2-ylcarbonyl, nicotinoyl, pyridin-2-ylmethylcarbonyl, isonicotinoyl, benzimidazol-5-ylcarbonyl, thenoyl, pyrrolidinylcarbonyl, piperidinylcarbonyl, 2,5-diazabicyclo[2.2. l]heptan-l-ylmethylcarbonyl, etc. The "halogen" includes fluoro, chloro, bromo and iodo, preferably, fluoro and chloro. The substituent in the "optionally substituted lower alky!" and " optionally substituted cycloalkyl" includes at least one member selected from Group a. The substituent in the "optionally substituted acyl," "optionally substituted lower alkyl-S02-" and "optionally substituted heterocyclic group-So2-" includes at least one member selected from Group b. Group a: (1) halogen, (2) HO, (3) a lower alkyl-O-, (4) H2N, (5) a lower alkyl-NH-, (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group; this heterocyclic group is preferably a monocyclic heterocyclic group. Group b: (1) HO, (2) a lower alkyl-O-, (3) R101R102N (wherein R101 and R102, which may be the same or different, represent (i) H, (ii) a lower alkyl which may optionally be substituted with HO, lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a lower alkyl-NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower alkyl)2N-, (iii) an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an aryl which may optionally be substituted with a halogen), (4) a halogen, (5) oxo (0=), (6)a cycloalkyl may optionally be substituted with R101R102N, (7)an aryl, (8)a heterocyclic group, (9) a lower alkyl which may optionally be substituted with HO, a lower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which may optionally be substituted with oxo (0=), (ll)H2N-CO-, (12) a lower alkyl-S02-, and (13) a heterocyclic group-S02-. In Compound (I) of the present invention, optical isomers (enantiomers, diastereomers, etc.) or geometrical isomers are present depending upon type of substituents. Consequently, Compound (I) of the present invention includes these optical isomers or geometrical isomers, either in the isolated form or as mixtures thereof. Compound (I) of the present invention may form a salt with an acid addition salt or with a base. Specific examples of such acid addition salts with an inorganic acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, nitric acid, phosphoric acid, etc.; with an organic acid such as formic acid, acetic acid, propionic acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid, lactic acid, malic acid, citric acid, tartaric acid, carbonic acid, picric acid, methanesulfonic acid, ethanesulfonic acid, glutamic acid, etc.; with an inorganic base such as sodium, potassium, magnesium, calcium, aluminum, etc., an organic base such as methylamine, ethylamine, monoethanolamine, diethanolamine, triethanolamine, cyclohexylamine, lysine, ornithine, etc. In addition, Compound (I) of the present invention or its pharmaceutically acceptable salts may form hydrates, solvates with ethanol, etc. or polymorphism. Furthermore, Compound (I) of the present invention includes all of so-called prodrugs, i.e., the compounds which can be metabolized in vivo and converted into Compound (I) of the present invention or its pharmaceutically acceptable salts. Examples of the group which forms the prodrugs of Compound (I) of the present invention are those described in Prog. Med. 5: 2157-2161 (1985) and those described in "Iyakuhin no Kaihatsu" (Development of Pharmaceuticals) published in 1990 by Hirokawa Shoten, Vol. 7, "Molecular Design", pages 163-198. Specifically, the group is a group, which can be converted into the primary amine or secondary amine, HO-, HO-CO-, etc. defined in the present invention, by hydrolysis or solvolysis or under physiological conditions. The prodrugs of HO- include, for example, an optionally substituted lower alkyl-COO-, an optionally substituted aryl-CO-O-, RO-CO-optionally substituted lower alkylene-CO-O- (wherein R represents H- or a lower alkyl; hereinafter the same), RO-CO-optionally substituted lower alkenylene-CO-O-, a RO-CO-lower alkylene-O-lower alkylene-CO-O-, RO-CO-CO-0-, ROS(=0)2-optionally substituted lower alkenylene-CO-O-, phthalidyl-O-, 5-methyl-l,3-dioxolen-2-on-4-yl-methyloxy, etc. [Processes for Production] Compound (I) of the present invention can be produced by applying a variety of synthesis techniques, using the characteristics based on its basic skeleton or type of substituents. Hereinafter, representative processes are described below. PROCESS 1: (wherein A, R1 - R13 and n have the same significance as defined above; hereinafter the same). Compound (la) of the present invention can be obtained by the Wittig reaction (Org. React., 14, 270-490 (1965)) of a phosphonium salt (II) with an aldehyde or ketone (III) in a conventional manner. A reaction solvent, which can be used, includes a solvent inert to this reaction, such as tetrahydrofuran, dioxane, dimethylformamide, dimethylsulfoxide, toluene, etc. As a base, there may be used sodium hydride, potassium tert-butoxide, sodium ethoxide, lithium diisopropylamide, etc. The reaction can be carried out under the conditions of cooling (e.g., -70°C) to heating. PROCESS 2: Compound (lb) of the present invention can be obtained by the aldol condensation (Org. React., 16,1-438 (1968)) of an aldehyde (TV) with a (V) in a conventional manner. A reaction solvent, which can be used, includes a solvent inert to this reaction, such as tetrahydrofuran, dioxane, dimethylformamide, dimethylsulfoxide, toluene, etc. The reaction may be carried out under basic conditions and in this case, sodium hydride, potassium tert-butoxide, sodium ethoxide, lithium diisopropylamide, lithium bis(trimethylsilyl)amide, etc. may be used. As an acid used when the reaction is carried out under acidic conditions, there may be used hydrochloric acid, trifluoroacetic acid, tosylic acid, boron trifluoride, aluminum trichloride, titanium tetrachloride, etc. The reaction can be carried out under the conditions of cooling (e.g., -70°C)to heating. (wherein M represents Li, MgCl, etc.; hereinafter the same). Compound (Ic) of the present invention can be obtained by the reaction of an aryl metal such as an aryl lithium, an aryl Grignard, etc. with a carbonyl compound in a conventional manner (Org. Synth. HI, 200 (1955); Org. React., 6, 339-366 (1964); Org. React., 8, 258-304 (1967)). A reaction solvent, which can be used, includes a solvent inert to this reaction, such as diethyl ether, tetrahydrofuran, dioxane, dimethylsulfoxide, toluene, etc. The reaction can be carried out under the conditions of cooling (e.g., -70°C) to heating. In addition to the processes described above, Compound (I) of the present invention can also be obtained, e.g., by the Peterson reaction (Org. React., 38, 1-223 (1990)), formation of triple bond followed by partial reduction (I. Am. Chem. Soc, 77, 3378 (1955); I. Am. Chem. Soc, 99, 2805 (1977); Synthesis, 1973, 457; Tetrahedron 30, 3817 (1974)), etc. (wherein R9a means R9 other than H and X1 means a leaving group such as a halogen, rnethanesulfonyloxy, p-toluenesulfonyloxy, etc.; hereinafter the same.) This process is alkylation. Specifically, the alkylation is carried out as in the processes described above, e.g., in a solvent inert to the reaction, using an amine (Id) and a compound (VIII) having a leaving group corresponding to the reaction in a chemically equivalent amount or in an excess of either reactant, under the conditions of cooling to heating. In some occasions, the reaction is carried out smoothly in the presence of a base (e.g., an inorganic base such as potassium carbonate, sodium carbonate, cesium carbonate, etc.; an organic base such as triethylamine, diisopropylethylamine, etc.; a metal alkoxides such as potassium tert-butoxide, sodium tert-butoxide, etc.; sodium hydride; lithium hydride; etc.), an additive (tetra-n-butylammonium iodide, potassium iodide, sodium iodide, etc.), which is advantageous. A reaction solvent, which can be used, includes a solvent inert to this reaction, such as tetrahydrofuran, dichloromethane, dichloroethane, acetonitrile, (wherein R9b-CO- represents an optionally substituted an acyl; and X2 represents OH; a leaving group such as a halogen, 1-hydroxybenzotriazol-l-yloxy, methoxy, phenoxy, azido, etc., or a leaving site in a mixed anhydride or a symmetric anhydride; hereinafter the same.) This process is amidation. Specifically, the amidation is carried out as in the processes described above, e.g., by reacting an amine (Id) with a carboxylic acid or its reactive derivative (IX) in a chemically equivalent amount in accordance with the processes described in, e.g., M. Bodanszky, "Peptide Chemistry" (1988, pages 55-73), Nobuo Izumiya, et. al, "Basis and Experimentals of Peptide Synthesis" (1985, pages 89-142), etc. Specifically, this reaction is preferably carried out by the method using a condensing agent conventionally used (dicyclohexylcarbodiimide, l-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 1,l'-carbonyldiimidazole (CDI), etc.); the mixed anhydride method using ethyl chloroformate or isobutyl chloroformate; the symmetric anhydride method using ethoxyacetylene, an alkynylamine such as tert-butylethynyldimethylamine, etc. If desired, a catalyst such as 1-hydroxybenzotriazole, etc. may be used. The reaction may also be carried out by reacting a carboxylic acid with a halogenating agent such as thionyl chloride, oxalyl chloride, phosphorus oxychloride, etc. to convert the acid into a reactive derivative such as an acid halide and then reacting the reactive derivative with a primary or secondary amine. The reaction is carried out in a solvent inert to this reaction such as tetrahydrofuran, dioxane, dichloromethane, dichloroethane, dimethylformamide, dimethylsulfoxide, toluene, etc., if necessary, in the presence of a base (e.g., an organic base such as triethylamine, diisopropylethylamine, pyridine, etc.; an inorganic base such as potassium carbonate, sodium hydrogencarbonate, etc.), under the conditions of ice cooling to heating with stirring. (wherein R9Crepresents a group having a carbon number less than by one from the optionally substituted lower alkyl shown by R9, hereinafter the same). This process is reductive amination. Specifically, the reaction is carried out as in the processes described above, e.g., by reacting an amine (Id) with an aldehyde or ketone (X) in a conventional manner of reductive amination, e.g., the process described in "Experimental Chemistry Series (Maruzen)" (4th edition, 20, 1992, page 300), edited by The Chemical Society of Iapan, etc. Specifically, Compound (Ig) can be produced by reacting the amine with its chemically equivalent amount of the aldehyde or ketone in a solvent inert to this reaction such as tetrahydrofuran, dioxane, dichloromethane, dichloroethane, dimethylformamide, dimethylsulfoxide, toluene, etc., in the presence of a reducing agent such as sodium cyanoborohydride, sodium triacetoxyborohydride, sodium borohydride, formic acid, etc., under the conditions of ice cooling to heating with stirring. In some occasions, the reaction is carried out smoothly in the presence of an acid (e.g., a Lewis acid such as titanium tetraisopropoxide, etc.; acetic acid; p-toluenesulfonic acid, etc.), which is advantageous. The reduction described above may also be performed in the above-described solvent inert to the reaction by catalytic reduction in the presence of a metal catalyst such as palladium (Pd), platinum (Pt), etc. The reducing agent may be added immediately after mixing the primary or secondary amine with the aldehyde or ketone or after passage of some time. The foregoing shows the processes for producing representative compounds. In addition, compounds other than the compounds of the present invention or raw compounds but having similar substituents can be subIected to reactions for modifying substituents according to the processes described above to produce the compounds of the present invention. In addition to the processes described above, these compounds can be produced by other well known processes, including conventional imidation or amidination, or by the processes described in "Experimental Chemistry Series (Maruzen)" (4th edition, 25, pages 396-427) edited by The Chemical Society of Iapan, Protective group Organic Synthesis, Second Ed., Iohn Wiley & Sons, Inc., or Angew. Chem. Int. Ed. Engl. 1998, 37, p2046-2067, etc. Compound (I) of the present invention thus produced is isolated in its free form or as its salt. The salt of Compound (I) of the present invention can be prepared by applying a conventional salt-making technique to Compound (I) of the present invention as the free base. Also, Compound (I) of the present invention or its salt may be isolated and purified in the form of a hydrate, solvate or polymorphism thereof. The isolation and purification are performed by applying conventional chemical operations including extraction, concentration, distillation, crystallization, filtration, recrystallization, various chromatography techniques, etc. Various isomers can be separated by choosing an appropriate raw compound, or by utilizing a difference between isomers in physical or chemical properties. For example, the optical isomers can be converted into stereochemically pure isomers, by choosing appropriate raw compounds or by racemic resolution of racemic compounds (for example, by a process of optical resolution which comprises converting the racemic compounds into diastereomer salts with ordinary optically active acids, etc.). [Formulation] Various formulations conventionally used are applicable to Compound (I) of the present invention. Representative formulations are explained below. A pharmaceutical composition may contain one or two or more types of the Compound (I) of the present invention or pharmaceutically acceptable salts thereof as the effective ingredient and pharmaceutically acceptable carriers, which can be prepared into tablets, powders, fine granules, granules, capsules, pills, liquids, inIections, suppositories, ointments, paps or the like, using carriers and excipients conventionally used to make pharmaceutical preparations, and other additives. The resulting formulations are administered orally (including sublingual administration) or parenterally. The clinical dose of Compound (I) of the present invention or pharmaceutically acceptable salts to human is appropriately determined, depending on the symptom, age, sex and body weight of an individual patient, to whom Compound (I) or pharmaceutically acceptable salts is applied. Generally, Compound (I) or pharmaceutically acceptable salts is orally administered to an adult at a dose of 1 mg to 1000 mg per day in one portion or divided portions in the form of a solid composition or a liquid composition. Alternatively, the compound is intravenously administered to an adult at a dose of 1 mg to 500 mg per day in one portion or divided portions, or intravenously administered in a sustained release manner for a period of 1 hour to 24 hours per day. As described above, since the dose may vary depending upon various conditions and thus, a dose below the range given above may be sometimes sufficient. As the solid composition for oral administration in accordance with the present invention, tablets, powders, granules and the like are used. For such solid composition, one or more active substances are mixed with at least one inactive diluent, for example lactose, mannitol, glucose, hydroxypropylcellulose, microcrystalline cellulose, starch, polyvinylpyrrolidone, or metasilicate aluminate magnesium. Following a conventional manner, the composition may further contain additives other than inactive diluents, for example, lubricants such as magnesium stearate, disintegrators such as cellulose calcium glycolate, stabilizers such as lactose, solubilization or dissolution-auxiliary agents such as glutamic acid or aspartic acid. The tablets or pills may be sugar-coated or coated with a gastric soluble or enteric film, using sucrose, gelatin, hydroxypropyl cellulose and hydroxypropylmethyl cellulose phthalate, and the like. The liquid composition for oral administration contains pharmaceutically acceptable emulsifiers, solubilizers, suspending agents, syrups, elixirs and the like and also contains inactive diluents conventionally used, for example, distilled water or ethyl alcohol. The composition may further contain auxiliary agents such as solubilization- or dissolution-auxiliary agents, moisturizers and suspending agents, sweeteners, flavoring agents, aromatic agents and preservatives. The inIections for parenteral administration include aseptic, aqueous or non-aqueous solubilizers, suspending agents and emulsifiers. Aqueous solubilizers and suspending agents include, for example, distilled water for inIections and physiological saline. Water-insoluble solubilizers and suspending agents include, for example, propylene glycol, polyethylene glycol, vegetable oils such as olive oil, alcohols such as ethanol, polysorbate 80 (trade name), etc. Such composition may further contain additives including isotonic agents, preservatives, moisturizers, emulsifiers, dispersants, stabilizers (for example, lactose), and solubilization- and dissolution-auxiliary agents. These are sterilized by filtration through, e.g., a bacteria retention filter, or by blending with sterilizers or irradiation. These may also be prepared into aseptic solid compositions and the resulting aseptic compositions are provided for use after dissolution in aseptic water or in an aseptic solvent for inIections, prior to use. Furthermore, Compound (I) of the present invention may be used in combination with therapeutics for the diseases described above or with other drugs useful for pain by a mechanism other than the sodium channel blockage. Drugs useful for pain, which are usable in combination, include narcotic analgesics, antipyretic analgesics, non-steroidal antiinflammatory drugs, etc. Examples Next, the present invention is described in more detail by referring to Examples but is not deemed to be limited thereto. Raw compounds used will be explained in Reference Examples. The chemical structures of individual compounds obtained in Examples, Example Nos. using the compounds and specific constructions are shown in Tables ] through 13 and the physicochemical properties of these compounds are shown in Tables 14 through 25 below. Production examples of the raw compounds used in Examples are specifically described by referring to Reference Examples 1 through 33. The chemical structures of the compounds obtained in Reference Examples 4 to 15, 17, 22 to 25, 28 to 29 and 31 to 32 are shown in Table 26 and the physicochemical properties of the compounds of Reference Examples 1 through 33 are shown in Table 27. Tables 1 to 25 relating to Examples and Tables 26 and 27 relating to Reference Examples are shown at the end of the specification. The symbols in Tables 1 to 25 relating to Examples and Tables 26 and 27 relating to Reference Examples are used to mean the following. Rf: Reference Example No., Ex.: Example No., Me: methyl, Et: ethyl, Pr: propyl, iPr: isopropyl, Bu: butyl, iBu: isobutyl, tBu: tert-butyl, Ph: phenyl, Ac: acetyl, Bn benzyl, cBu: cyclobutyl, cPen: cyclopentyl, cHex: cyclohexyl, cHep: cycloheptyl, Mo: morpholine, ThioMo: thiomorpholine, Py: pyridine, Pyrrolid: pyrrolidine, Piperi: piperidine, Pipera: piperazine, TM: imidazole, MeO: methoxy, EtO: ethoxy, Me2N: dimethylamino, PhO: phenoxy, BU2N: dibutylamino, yl: yl, Salt: salt, fum: fumarate, difumarate: difumarate, dimaleate: dimaleate, Structure: structural formula, NMR: nuclear magnetic resonance spectrum (unless otherwise indicated, 400 MHz, DMSO-d6, TMS internal standard, ppm), MS: mass spectrum (unless otherwise indicated, FAB or ESIm/z), Data: physicochemical property. Reference Example 1 1) 3.32 g of aniline was added to a solution of 4.99 g of 2-chlorobenzaldehyde in 48 ml of benzene, and the mixture was heated under reflux for 20 hours. After the reaction mixture was concentrated under reduced pressure, the concentrate was azeotropically distilled with toluene to give 6.16 g of yellow oil. The yellow oil was dissolved in 120 ml of acetic acid and 5.45 g of palladium acetate was added to the solution, followed by heating under reflux for 2 hours. After cooling, water was added to the reaction mixture and the precipitated crystals were collected by filtration. The crystals were dissolved in 50 ml of methylene chloride, and 75 ml of saturated aqueous sodium chloride and 50 ml of acetone were added to the solution. The mixture was stirred at ambient temperature for 15 hours. The precipitated crystals were collected by filtration and washed with ethanol, benzene and methylene chloride to give 5.50 g of green crystals. The crystals were suspended in 250 ml of benzene and 8.08 g of triphenylphosphine was added to the suspension, followed by stirring at ambient temperature for 50 minutes. To the reaction mixture was added 13 ml of 1.2M methyl lithium in diethyl ether .The mixture was stirred for 2 hours and 250 ml of IN hydrochloric acid was further added thereto, followed by stirring for 2 hours. The reaction mixture was extracted with diethyl ether. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 1.51 g of 2-chloro-6-methylbenzaldehyde as pale yellow oil. 2) Under ice cooling, 185 mg of sodium borohydride was added to a solution of 1.51 g of 2-chloro-6-methylbenzaldehyde in 15 ml of methanol, followed by stirring for 35 minutes. The reaction mixture was concentrated under reduced pressure and saturated aqueous ammonium chloride was added to the residue. The mixture was extracted with diethyl ether. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by 126 ml of triethylamine and 36.0 g of molecular sieves (4A), and the mixture was heated under reflux for 47 hours. The reaction mixture was filtered and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane) to give 5.23 g of colorless oil. Grignard reagent was prepared from the oil, 0.51 g of magnesium and 25 ml of tetrahydrofuran. Under ice cooling, a solution of 1.27 g of dimethylformamide in 15 ml of tetrahydrofuran was added dropwise to the reagent. After stirring at ambient temperature for 45 minutes., the reaction mixture was poured into saturated aqueous ammonium chloride, followed by extraction with diethyl ether. The organic layer was washed with saturated aqueous sodium chloride and then dried over anyhydrous sodium sulfate and the solvent was evaporated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 3.79 g of pale yellow oil. This oil was dissolved in 40 ml of methanol. Under ice cooling, 0.32 g of sodium borohydride was added to the solution, followed by stirring at ambient temperature for 45 minutes. The reaction mixture was concentrated under reduced pressure and saturated aqueous ammonium chloride solution was added to the residue, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure to give 3.78 g of (2,6-dimethyl-4-phenoxyphenyl)methanol. The compound of Reference Example 4 was obtained in a manner similar to Reference Example 3. The compounds of Reference Example 5 to 15 were obtained in a manner similar to Reference Example 1. Reference Example 16 After 4.34 g of N-bromosuccinimide and 0.54 g of benzoyl peroxide were added to a solution of 3.03 g of 2,3-dimethylanisole in 70 ml of carbon tetrachloride, the mixture was heated under reflux for 30 minutes. After cooling, insoluble solid in the reaction mixture were filtered off and the filtrate was concentrated under reduced pressure to give an oil. The obtained oil was dissolved in 50 ml of benzene, and 5.82 g of triphenylphosphine was added to the solution. The mixture was heated under reflux for 11 hours. After cooling, the precipitated crystals were collected by filtration and recrystallized from methylene chloride-benzene to give 6.51 g of (2-methoxy-6-methylbenzyl)(triphenyl)phosphonium bromide as colorless crystals. The compound of Reference Example 17 was obtained in a manner similar to Reference Example 16. Reference Example 18 After 10.4 g of potassium carbonate and 6.80 ml of methyl iodide were added to a solution of 10.0 g of 4-bromo-3,5-dimethylphenol in 100 ml of acetone, the mixture was heated under reflux for 15 hours. The reaction mixture was concentrated under reduced pressure and saturated aqueous ammonium chloride was added to the residue, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 9.18 g of 4-bromo-3,5-dimethylanisole as colorless oil. Reference Example 19 Ethyl 4-(hydroxyimino)cyclohexanecarboxylate was reacted in the presence of cone, sulfuric acid in ethanol to produce ethyl 7-oxoazepane-4-carboxylate. Reference Example 20 Ethyl 7-oxoazepane-4-carboxylate was reacted in the presence of lithium aluminum hydride to produce azepan-4-ylmethanol. Reference Example 21 8.60 ml of di-tert-butyl dicarbonate was added to a solution of 5.00 g of 2-piperidin-4-ylethanol in 50 ml of tetrahydrofuran, followed by stirring at ambient temperature for 30 minutes. The reaction mixture was concentrated under reduced pressure and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 8.80 g of an oil. The oil was dissolved in 60 ml of dimethylsulfoxide, and the resulting solution was added 20.5 ml of triethylamine and 12.2 g of sulfur trioxide-pyridine complex, followed by stirring at ambient temperature for 30 minutes. The reaction mixture was poured into saturated aqueous sodium bicarbonate, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 6.40 g of tert-butyl 4-(2-oxoethyl)piperidine-1 -carboxylate. The compounds of Reference Examples 22 to 25 were produced in a manner similar to Reference Example 21. Reference Example 26 (1 -Benzylpyrolidin-3-yl)methanol was reacted in the presence of triethylamine and sulfur trioxide-pyridine complex in dimethylsulfoxide to produce 1 benzylpyrrolidine-3-carbaldehyde. Reference Example 27 tert-Butyl 3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylate was reacted in the presence of p-toluenesulfonylmethylisocyanide, potassium tert-butoxide and ethanol in 1,2-dimethoxyethane to produce tert-butyl 3-cyano-8-azabicyclo[3.2.1]bctane-8-carboxylate. The compounds of Reference Examples 28 to 29 were produced in a manner similar to Reference Example 27. Reference Example 30 tert-Butyl 3-cyano-8-azabicyclo[3.2.1]octane-8-carboxylate was reacted in the presence of diisobutyl aluminum hydride in tetrahydrofuran to produce tert-butyl 3-formyl-8-azabicyclo[3.2.1]octane-8-carboxylate. The compounds of Reference Examples 31 to 32 were produced in a manner similar to Reference Example 30. Reference Example 33 Under ice cooling, 18 ml of 2-(bromomethyl)-l,3-dioxolane, 9.87 g of potassium tert-butoxide and 6.57 g of tetrabutylammonium iodide were added to a solution of 14.0 g of methyl 2-oxopiperidine-4-carboxylate in 300 ml of tetrahydrofuran and 50 ml of dimethylformamide, and the mixture was stirred at 70°C for 14 hours. The reaction mixture was poured into water, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 4.50 g of yellow oil. This oil was dissolved in 90 ml of tetrahydrofuran and 1.00 g of lithium borohydride was added to the solution under ice cooling, followed by stirring at ambient temperature for 4 hours. After saturated aqueous ammonium chloride solution was added to the reaction mixture, the mixture was extracted with chloroform. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (chloroform-methanol) to give 2.60 g of colorless oil. This oil was dissolved in 30 ml of dimethylsulfoxide, and 5.14 g of triethylamine and 4.04 g of sulfur trioxide-pyridine complex were added to the solution, followed by stirring at ambient temperature for 1.5 hour. The reaction mixture was poured into water, followed by extraction with chloroform. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure to give 2.36 g of l-(l,3-dioxolan-2-ylmethyl)-2-oxopiperidine-4-carbaldehyde. Example 1 264 mg of sodium hydride (55%) was added to a solution of 2.65 g of (2-chloro-6-methylbenzyl)(triphenyl)phosphonium chloride in 20 ml of dimethylsulfoxide, followed by stirring at ambient temperature for 1 hour. After 994 mg of tert-butyl 4-formylpiperidine-l-carboxylate was added to the reaction mixture, the mixture was stirred at ambient temperature for 1 hour. The reaction mixture was poured into saturated aqueous ammonium chloride, followed by extraction with ethyl acetate. The organic layer was washed with water and saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 645 mg of tert-butyl 4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine-l-carboxylate as an oil. Example 2 As starting materials, 5.00 g of (2,6-dimethylbenzyl)(triphenyl)phosphonium chloride and 1.79 g of tert-butyl 4-formylpiperidine-l-carboxylate were used and treated in the same manner as in Example 1. The reaction mixture was then purified by silica gel column chromatography (hexane-ethyl acetate) to give 192 mg of tert-butyl 4-[(Z)-2-(2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate (Example 2-1) and 1.96 g of tert-butyl 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate (Example 2-2). The compounds of Examples 3 to 14, 16 to 24, 27 and 28 were produced in a manner similar to Example 1. The compounds of Examples 15-1, 15-2, 25-1, 25-2, 26-1 and 26-2 were produced in a manner similar to Example 2. Example 29 Under argon atmosphere, 1M tetrahydrofuran solution of 1.3 ml of lithium bis(trimethylsilyl)amide was added at -78°C to a solution of 300 mg of tert-butyl 4-acetylpiperidine-l-carboxylate in 4.0 ml of tetrahydrofuran, followed by stirring for 15 minutes. To the reaction mixture, a solution of 167 mg of 2,6-dimethylbenzaldehyde in 1.0 ml of tetrahydrofuran was added, followed by stirring at ambient temperature for 12 hours. Saturated aqueous ammonium chloride solution was added to the reaction mixture, followed by extraction with diethyl ether. The organic layer was washed with water and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 235 mg of tert-butyl 4-[(E)- 3 -(2,6-dimethylphenyl)prop-2-enoyl]piperi dine-1 -carboxylate. Example 30 Under cooling at -78°C, a solution of 1.50 g of 4-bromo-2,6-dimethylanisole in 20 ml of tetrahydrofuran was added to a solution of 1.6M hexane solution of 4.8 ml of n-butyl lithium in 20 ml of tetrahydrofuran. The mixture was stirred for 1 hour. A solution of 1.50 g of tert-butyl 4-(2-oxoethyl)piperidine-l-carboxylate in 20 ml of tetrahydrofuran was added to the mixture. After stirring for 30 minutes, the mixture was stirred at ambient temperature for further 3 hours. The reaction mixture was poured into water, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 628 mg of tert-butyl 4-[2-hydroxy-2-(4-methoxy-2,6-dimethylphenyl)ethyl]piperidine-l-carboxylate as an oil. To the oil was added 15 ml of 10% hydrochloric acid and the mixture was heated under reflux for 2 hours. After cooling, the reaction mixture was alkalized with 20% aqueous sodium hydroxide solution,, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure to give 291 mg of tert-butyl 4-[(E)-2-(4-methoxy-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate. Example 31 Under argon atmosphere, 3 ml of propionitrile was added to a mixture of 339 mg of tert-butyl 4-[(E)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate, 89 mg of sodium cyanide, 53 mg of tetrakistriphenylphosphine palladium and 17 mg of copper iodide., followed by heating under reflux for 7 hours. Water was added to the reaction mixture, followed by extraction with ethyl acetate. The extract was dried over anhydrous magnesium sulfate and the residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 299 mg of tert-butyl 4-[(E)-2-(4-cyano-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate. Example 32 Under carbon monoxide atmosphere, 120 u.1 of butanol and 265 u,l of tributylamine were added to a mixture of 409 mg of tert-butyl 4-[0i)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate and 39 mg of dichlorobistriphenylphosphine palladium. The mixture was heated at 100°C overnight with stirring. Then 87 mg of dichlorobistriphenylphosphine palladium, 120 u.1 of butanol and 265 μ1 of tributylamine were added to the reaction mixture and the mixture was heated at 120°C overnight with stirring. Water was added to the reaction mixture, followed by extraction with ethyl acetate. The organic layer was washed sequentially with 0.1N hydrochloric acid, saturated aqueous sodium hydrogen carbonate solution, water and saturated aqueous sodium chloride. After drying over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 217 mg of tert-butyl 4-{(E)-2-[4-(butoxycarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate (Example 32-1) and 123 mg of tert-butyl 4-((E)-2-{4-[(dibutylamino)carbonyl]- 2,6-dimethylphenyl}vinyl)piperidine-l-carboxylate (Example 32-2). Example 33 Under argon atmosphere, 10 ml of toluene and 87 μl of morpholine were added to a mixture of 300 mg of tert-butyl 4-[(E)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate, 110 mg of sodium tert-butoxide, 45 mg of bisdibenzylideneacetone palladium and 48 mg of BINAP. The resulting mixture was heated at 100°C for 11 hours with stirring. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 289 mg of tert-butyl 4-[(E)-2-(2,6-dimethylphenyl-4-morpholin-4-yl-phenyl)vinyl]piperidine-l- carboxylate. The compound of Example 34 was produced in a manner similar to Example 33. Example 3 5 To a suspension of 133 mg of tert-butyl 4-[(E)-2-(4-cyano-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate in 5 ml of acetone and 2 ml of water, 146 mg of hydrogen peroxide-urea complex and 7 mg of potassium carbonate were added, followed by stirring overnight. Then, 221 mg of hydrogen peroxide-urea complex was added and the mixture was stirred overnight, and 293 mg of hydrogen peroxide-urea complex was further added, followed by stirring for 4 days. An aqueous solution of sodium sulfate was added to the reaction mixture and extracted with chloroform. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (chloroform-methanol) to give 134 mg of tert-butyl 4-{(E)-2-[4-(aminocarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate. Example 36 To a solution of 209 mg of tert-butyl 4-{(E)-2-[4-(butoxycarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate in 5 ml of ethanol, 1.5 ml of IN aqueous sodium hydroxide solution was added, followed by stirring at ambient temperature for 3.5 hours. After 1 ml of tetrahydrofuran was added to the reaction mixture, the mixture was stirred at 50°C overnight. The solvent was evaporated under reduced pressure, water and 1.6 ml of IN hydrochloric acid were added thereto. The formed precipitates were collected by filtration and dried to give 179 mg of 4-{(E)-2-[l-(tert-butoxycarbonyl)piperidin-4-yl]vinyl}-3,5-dimethylbenzoicacid. Example 37 To a solution of 645 mg of tert-butyl 4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine-l-carboxylate in 4 ml of ethanol, 3 ml of 35% hydrogen chloride-ethanol was added, followed by stirring at ambient temperature for 5 hours. The reaction mixture was evaporated under reduced pressure and the residue was azeotropically distilled with 5 ml of toluene 3 times to give crystals. The collected crystals were recrystallized from ethanol-ethyl acetate to give 377 mg of 4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine hydrochloride. The compounds of Examples 38 to 67 were produced in a manner similar to Example 37. Example 68 To a solution of 125 mg of l-benzyl-4-[(E)-2-(2,6-dimethylphenyl)vinyl]-3-methylpiperidine in 3 ml of 1,2-dichloroethane, 139 mg of 1-chloroethyl chlorofofmate was added at ambient temperature. The mixture was heated under reflux for 1 hour. After cooling, 10 ml of methanol was added to the reaction mixture and the resulting mixture was heated under reflux for further 30 minutes. After cooling, the solvent was evaporated under reduced pressure. The residue was dissolved in 5 ml of ethyl acetate and the solution was filtered. To the filtrate was added 1 ml of 4N hydrochloric acid-ethyl acetate and the solvent was evaporated under reduced pressure. The residue was triturated in ethyl acetate. After filtration, the obtained solid was recrystallized from ethyl acetate-methanol to give 47 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-3-methylpiperidine hydrochloride. The compound of Example 69 was produced in a manner similar to Example 68. Example 70 To a solution of 520 mg of 2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine rnonohydrochloride in 7 ml of dimethylformamide, 0.13 ml of methyl iodide, 0.58 ml of triethylarnine and 572 mg of potassium carbonate were added, followed by stirring at ambient temperature for 12 hours. The reaction mixture was poured into water, followed by extraction with ethyl acetate. The organic layer was washed with saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue was purified by silica gel column chromatography (chloroform-methanol) to give 470 mg of 2 -[(E)-2-(2,6-dimethylphenyl)vinyl]-l-methylpiperidine. The product was dissolved in 5 ml of ethanol, and 2.5 ml of 35% hydrogen chloride-ethanol was added to the solution, followed by stirring at ambient temperature for 1 hour. The reaction mixture was evaporated under reduced pressure and the residue was azeotropically distilled with 5 ml of toluene 3 times to give crystals. The collected crystals were recrystallized from ethanol-ethyl acetate to give 395 mg of 2-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-methylpiperidine rnonohydrochloride. The compounds of Examples 71 to 77 were produced in a manner similar to Example 70. Example 78 Under ice cooling, 6.77 ml of triethylarnine and 3.87 ml of chloroacetyl chloride were added to a solution of 9.96 g of 4-[(E)-2-(2.6-dimethylphenyl)vinyl]piperidine in 150 ml of tetrahydrofuran. After stirring at ambient temperature for 20 minutes, 200 ml of water was added to the mixture. After the organic layer was fractionated, the aqueous layer was extracted with diethyl ether. The combined organic layer was and washed with saturated aqueous sodium chloride. After drying over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate). The collected crystals were washed with diisopropyl ether-hexane and dried under reduced pressure to give 10.69 gof l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine. The compounds of Examples 79 to 84 were produced in a manner similar to Example 78. Example 8.5 To a solution of 200 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride in 5 ml of dimethylformamide, 111 μl oftriethylamine, 107 mg of imidazole-4-carboxylic acid, 161 mg of 1-hydroxybenzotriazole and 228 mg of 1 -ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride were added at ambient temperature. After stirring at ambient temperature overnight, the reaction mixture was concentrated under reduced pressure. After 50 ml of chloroform and 15 ml of saturated aqueous sodium hydrogen carbonate solution were added to the reaction mixture, the organic layer was fractionated and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroforrn-methanol-ammonia water) to give 280 mg of colorless oil. The oil obtained was dissolved in 2 ml of ethanol, and 226 \x\ of 4N hydrochloric acid-ethyl acetate was added to the solution. The precipitated crystals were collected by filtration and washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether to give 191 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-(lH-imidazol-4-ylcarbonyl)piperidine monohydrochloride. The compounds of Examples 86 to 107 were produced in a manner similar to Example 85. Example 108 To a solution of 250 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride in 5 ml of dimethylformamide, 138 \|_tl oftriethylamine, 222 mg of 2-[(tert-butoxycarbonyl)amino]-2-methylpropionic acid, 201 mg of I-hydroxybenzotriazole and 286 mg of l-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride were added at ambient temperature. After stirring at ambient temperature overnight, the reaction mixture was concentrated under reduced pressure. After 50 ml of chloroform and 15 ml of saturated aqueous sodium hydrogencarbonate solution were added to the residue, the organic layer was fractionated and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane-ethyl acetate) to give 364 mg of white crystals. The collected crystals were dissolved in 5 ml of 4N hydrochloric acid-ethyl acetate. After stirring at ambient temperature for 1 hour, 10 ml of diethyl ether was added to the solution, followed by stirring for 30 minutes. The precipitated crystals were collected by filtration and washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether to give 227 mg of (2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-l,l- dimethyl-2-oxoethyl)amine monohydrochloride. The compounds of Examples 109 to 122 were produced in a manner similar to Example 108. Example 123 To a solution of 300 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride in 5 ml of ethanol, 736 mg of ethyl acetimidate hydrochloride and 996 μ1 of triethylamine were added at ambient temperature. After stirring at ambient temperature overnight, the reaction mixture was concentrated under reduced pressure After 50 ml of chloroform and 15 ml of saturated aqueous sodium hydrogencarbonate solution were added to the reaction mixture, the organic layer was fractionated and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform-methanol-ammonia water) to give 313 mg of pale yellow crystals. The collected crystals were dissolved in 5 ml of ethanol, and 305 μ1 of 4N hydrochloric acid-ethyl acetate was added to the solution. The solvent was evaporated under reduced pressure. The residue was crystallized from ethanol-diethyl ether and the precipitated crystals were collected by filtration and washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether to give 89 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(1 -iminoethyl)piperidine monohydrochloride. Example 124 349 mg of lH-pyrazole-1-carboxamidine and 1.45 ml of N,N-diiso propylethylamine were added to a solution of 300 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride in 5 ml of dimethylformamide at ambient temperature. After stirring at ambient temperature overnight, the reaction mixture was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate-ethanol-water) to give 427 mg of white crystals. The obtained crystals were dissolved in 5 ml of methanol, and 415 u,l of 4N hydrochloric acid-ethyl acetate was added to the solution. The solvent was evaporated under reduced pressure and the residue was crystallized from ethanol-diethyl ether. The precipitated crystals were collected by filtration and washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether to give 154 mg of l-amidino-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride. Example 125 84 mg of IH-imidazole and 142 mg of potassium carbonate were added to a solution of 300 mg of l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidinein 5 ml of acetonitrile, followed by heating under reflux for 3 hours. After cooling, saturated aqueous sodium hydrogencarbonate solution was added to the reaction mixture, followed by extraction with chloroform. The organic layer was concentrated under reduced pressure and the residue was purified by silica gel column chromatography (chloroform-methanol-ammonia water) to give 314 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-(lH-imidazol-l-ylacetyl)piperidine as yellow crystals. A portion of 288 mg from the crystals was dissolved in 2 ml of ethanol and 334 μ1 of 4N hydrochloric acid-ethyl acetate was added to the solution, followed by concentrating under reduced pressure. The residue was crystallized from ethanol-diethyl ether and the crystals were collected by filtration. The crystals were then washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether to give 188 mg of 4- [(E)-2-(2,6-dimethylphenyl) vinyl] -1 -(1 H-imid azol-1 -ylacetyl)piperi dine monohydrochloride. The compounds of Examples 126 to 196 were produced in a manner similar to Example 125. Example 197 329 mg of tert-butyl (3S)-piperidin-3-ylcarbamate and 189 mg of potassium carbonate were added to a solution of 400 mg of l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine in 10 ml of acetonitrile, followed by heating u+nder reflux for 2 hours. After the reaction mixture was concentrated under reduced pressure, chloroform and saturated aqueous sodium hydrogencarbonate solution were added to the residue, then the organic layer was fractionated. The solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform-methanol-ammonia water). The obtained oil was dissolved in 10 ml of ethanol, and 10 ml of 4N hydrochloric acid-ethyl acetate was added to the solution, followed by stirring at ambient temperature for 3 hours. The reaction mixture was concentrated under reduced pressure and the resulting residue was crystallized from 2-propanol-diisopropyl ether. The crystals were recrystallized from water-ethanol to give 473 mg of (3S)-l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2- oxoethyl)p:iperidine-3-amine dihydrochloride. The compounds of Examples 198 to 206 were produced in a manner similar to Example 197. Example 207 454 ul of 37% aqueous formaldehyde solution and 175 ul of acetic acid were added to a solution of 219 mg of (2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)tetrahydro-2H- pyran-4-ylamine in 5 ml of dichloroethane, followed by stirring at ambient Temperature for 2 hours. Subsequently, 388 mg of sodium triacetoxyborohydride was added to the reaction mixture, followed by stirring at ambient temperature for 1 hour. Saturated aqueous sodium hydrogencarbonate solution and chloroform were added to the mixture, then the organic layer was fractionated and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform-methanol-ammonia water). The resulting oil was dissolved in 5 ml of ethanol, and 172 u.1 of 4N hydrochloric acid-ethyl acetate was added to the mixture. The solvent was evaporated under reduced pressure. The residue was crystallized from 2-propanol-diisopropyl ether. The crystals were recrystallized from 2-propanol-diisopropyl ether to give 201 mg of (2-{4-[(E)- 2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)methyl(tetrahydro-2H- pyran-4-yl)aminemonohydrochloride. The compounds of Examples 208 to 222 were produced in a manner similar to Example 207. Example 223 A solution of 200 mg of 4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl}-2-oxoethyl)morpholine in 1 ml of tetrahydrofuran was added dropwise to a suspension of 42 mg of lithium aluminum hydride in 6 ml of tetrahydrofuran under ice cooling, followed by heating under reflux for 2 hours. The mixture was then allowed to cool. Under ice cooling, 42 μ1 of water, 42 μl of 15% aqueous sodium hydroxide solution and then 126 ul of water were sequentially added to the reaction mixture. After stirring at ambient temperature for 30 minutes, 500 mg of anhydrous sodium sulfate was added and insoluble solid was filtered. The filtrate was evaporated under reduced pressure and the residue was purified by silica gel column chromatography (chloroforrn-methanol-ammonia water) to give 150 mg of yellow oil. Aportion of 143 mg from the oil was dissolved in 5 ml of ethyl acetate, and 2 ml of 4N hydrochloric acid-ethyl acetate was added to the solution. The solvent was evaporated under reduced pressure and the residue was washed with acetonitrile to give 133 mg of 4-(2- {4-[\|E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} ethy l)morpholine dihydrochloride. The compound of Example 224 was produced in a manner similar to Example 223. Example 225 675 μl of morpholine was added dropwise to a solution of 380 mg of l-(acryloyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine in 10 ml of toluene. The mixture was heated under reflux for 2 days in total. After the reaction mixture was concentrated under reduced pressure, the residue was purified by silica gel column chromatography (chloroforrn-methanol-ammonia water). The obtained oil was dissolved in 5 ml of ethanol, and 2 ml of 4N hydrochloric acid-ethyl acetate was added to the solution. The solvent was evaporated under reduced pressure. The precipitated crystals were recrystallized from ethanol to give 450 mg of 4-(3-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-3-oxopropyl)morpholine monohydrochloride. Example 226 After 3 ml of 10% hydrochloric acid was added to a solution of 818 mg of 4 -[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(1,3-dioxolane-2-ylmethyl)piperidin-2-one in 10 ml of tetrahydrofuran, the mixture was heated under reflux for 4.5 hours. After cooling, the reaction mixture was poured into saturated aqueous sodium hydrogen carbonate solution and extracted with ethyl acetate. The organic layer was washed with water and saturated aqueous sodium chloride. After drying over anhydrous sodium sulfate, the solvent was evaporated under reduced pressure to give 685 mg of {4-[(E)-2-(2,6-dimethylphenyl)vinyl]-2-oxopiperidin-l-yl}acetaldehyde. In addition to the compounds described in Examples, the compounds given in Tables 28 to 30 can be obtained by the processes described above, the processes described in Reference Examples and Examples, processes known to ordinary skill in the art and their modifications, without requiring any special experiments. Tables 28 to 30 are placed at the end of the specification, following Tables 1 to 27. INDUSTRIAL APPLICABILITY The compounds of the present invention have the sodium channel inhibitory action and are useful as pharmaceuticals, especially therapeutics for diseases associated with sodium channel and symptoms accompanied by these diseases, preferably as analgesics for neuropathic pain. For example, neuropathic pain means a pain caused by dysfunction of the central or peripheral nervous system and includes diabetic neuropathic pain, etc. [Pharmacological Tests] Hereinafter, experiments on the sodium channel inhibitory action using representative compounds of the present invention and animal tests using mice and rats are described in detail. (Experiment on sodium channel inhibitory action) The sodium channel inhibitory action of representative compounds in Compound (I) of the present invention was confirmed by experiment of [14C] guanidine uptake using rat brain tissues. The [14C] guanidine uptake experiment was performed by the method of Bonisch et al.(British Iournal of Pharmacology 108, 436-442, 1993) with some modifications. The [14C] guanidine was used as a sodium tracer, and the inhibitory activity on uptake of [ C] guanidine induced by veratridine as a sodium channel activator into rat cerebral cortex primary neurons was measured. a. Preparation of rat cerebral cortex primary neuron culture system Pregnant rats (Wistar, female, 19 days of gestation) were anesthetized with ether. The animals were bled to death by giving incision through the carotid artery. The fetuses were taken out of the pregnant rats and after ethanol sterilization, the cerebral cortex was removed from the fetuses. The cerebral cortex was digested with papain and dispersed in culture medium, followed by plating on a poly-L-lysine-coated 96-well white plate at a density of 2.5 x 105 cells/well. Incubation was performed in a CO2 incubator (37°C, 5% CO2) for 2 days. b. Assessment of test compounds After each well was washed once with an assay buffer (135 mM choline CI, 5 mM KC1, 1 mM MgS04, 5.5 mM glucose, 1 mg/mL BS A, 10 mM Hepes-Tris, pH 7.4), a fresh assay buffer was added to the well, followed by incubation at 25°C for 10 minutes. Then, a reaction solution (a test compound, [14C] guanidine and 100 \|I.M veratridine) was replaced for the buffer, followed by incubation at 25°C for 15 minutes. The reaction was terminated by washing 3 times with a cold wash buffer (135 mMNaCl, 5 mM KC1, 1 mMMgS04, 10 mM Hepes-Tris, pH 7.4). To each well, 17 \xL of O.lNNaOH was added. After agitation, 100 uL of scintillator was added to the well and further agitation was continued. The radioactivity was quantified by a liquid scintillation counter. In each experiment, the sodium channel-specific uptake of the whole uptake was designated as portion that was inhibited by 1 mM mexiletine. The action of the test compound on sodium channel is expressed as 50% inhibition concentration(ICso) based on the specific uptake. As shown in Table 31, the compounds of the present invention exhibited excellent inhibitory action. (Analgesic action on animal with streptozotocin-induced diabetic neuropathy) Representative compounds of Compound (I) of the present invention were assessed for the analgesic action in mice with streptozotocin (STZ)-induced diabetic neuropathy to confirm the effect on neuropathic pain. The assessment was performed by the method of Kamei et al. (Pharmacology Biochemistry & Behavior 39, 541-544, 1991) with some modifications. Male ICR mice of 4 weeks old were intraperitoneally inIected with 200 mg/kg weight of STZ to prepare mice with diabetic neuropathic pain. The analgesic action was assessed by the tail pinch test. Specifically, the analgesic action was detected as prolongation in withdrawal latency (in seconds), i.e., the time until the animal showed head-turning response after the tail was pinched with forceps. On Day 14 following the STZ inIection, a pretest was carried out to determine the response latency before the administration of a test compound. Only the animals showing not longer than 3 seconds of the response latency in the pretest were used for the test compound assessment on the following day (Day 15 after STZ inIection). In the test compound assessment, the response latency after the administration of a test compound was measured. The test compound was orally administered at a dose of 30 mg/kg, 45 minutes prior to the response latency measurement The analgesic action of a test compound is expressed as prolongation of latency (in seconds) calculated by the formula: (response latency after administration of a test compound) - (response latency before administration of a test compound). As shown in Table 32, the representative compounds of the present invention displayed the prolongation of latency (in seconds) of about 1 to 5 seconds. Separately, a test was conducted in a similar fashion, using a solvent (10% w/w DMSO/water) in place of the compound of the present invention. The results indicate that the prolongation of latency (in seconds) was 0.69 ± 0.38 second (mean + standard error). Generally in this analgesic test, the prolongation of at least about 1 second is considered to be effective and when the prolongation is longer than 1.5 second, the activity is rated as excellent; when the prolongation exceeds about 2 seconds, the analgesic action is rated as extremely excellent. Accordingly, the compounds tested in Examples have more excellent activities as compared to those of Comparative Examples 1 and 2. Mexiletine showed the prolongation of about 3 seconds. . Comparative Example 1: Compound described in Example 308 (Patent Literature 1: EPC 1254904) Comparative Example 2: Compound described in Example 334 (Patent Literature 1: EPC 1254904) (Anti-allodynia effect in rats with L5/L6 spinal nerve ligation) One of the maIor symptoms in neuropathic pain is a markedly lowered threshold of response to tactile stimulation (allodynia). The anti-allodynia effect of the representative compounds in the compounds of the present invention was confirmed by assessing the analgesic action in L5/L6 spinal nerve ligation rats. The assessment was performed by the method of Kim and Chung (Pain 50, 355-363, 1992) with some modifications. Under pentobarbital anesthesia, male SD rats of 5 or 6 weeks old were given surgery to ligate both the left L5 and L6 lumbar nerves tightly with silk threads. For the assessment of analgesic action, the von Frey hair test was adopted. That is, the animal's hindpaw was picked with hair and the lowest strength of hair for limb withdrawal response was designated as a response threshold (log gram) to mechanical stimulation. Since it was confirmed in prior test that the response threshold of the animal's hindpaw ipsilateral to the side of ligation was markedly low during days 7 to 14 after the surgery (in the state of allodynia), the anti-allodynia effect of a test compound was assessed on any day between days 7 and 14 from the surgery. On the day before the assessment of a test compound, the response threshold before administration of a test compound was measured. The animals were divided into 4 to 5 groups so that differences in the mean values of response thresholds before administration among the groups and variation within groups become small. In the assessment of a test compound, the response threshold after administration of the test compound was measured. The test compound was orally given 30 minutes before measurement of the response threshold. The anti-allodynia action potency of a test compound is expressed as ED50. In the calculation of the ED50, the thresholds of ipsilateral and contralateral paws in the solvent group were designated as 0% and ] 00%, respectively. Compounds having excellent ED50 values were found in the compounds of the present invention, whereas mexiletine showed ED50 value of about 70 mg/kg. It was confirmed by the test described above that the representative compounds in the compounds of the present invention show the sodium channel inhibitory action. It was also confirmed that these compounds with oral administration exhibited the analgesic action, that was more excellent than that of heretofore known compounds, in the disease animal models, i.e., mice with diabetic neuropathy and L5/L6 spinal nerve ligation rats. Based on the foregoing results, it was confirmed that some compounds of Compound (I) of the present invention showed sodium channel inhibitory action that was more excellent than that of mexiletine. It was also confirmed that some compounds of Compound(I) of the present invention with oral administration showed analgesic action that was equal or superior to that of mexiletine in the animal disease model, i.e., mice with diabetic neuropathy. Based on the evidence mentioned above, it was confirmed that the compounds of the present invention are excellent sodium channel inhibitors and are useful for relief of pain, especially neuropathic pain such as pain accompanied by diabetic neuropathy, etc. , / 1. A nitrogen-containing heterocyclic derivative represented by formula (I) below: (wherein symbols in formula (I) above have the following significance: R1 and R2, which may be the same or different, represent H-, an optionally substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower alkyl-O-CO-, H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an aryl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl^N-, an acyl-NH-, a halogen, nitro, a heterocyclic group, or cyano; R~' and R4, which may be the same or different, represent an optionally substituted lower alkyl, a cycloalkyl, an acyl, HO-CO-, a lower alkyl-O-CO-, H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a halogen, nitro, or cyano; R and R6, which may be the same or different, represent H-, a lower alkyl, or a halogen; R and R8, which may be the same or different, represent H-, a lower alkyl, HO-, a lower alkyl-O-, or a halogen; R and R8 may be combined together to form oxo (0=); R!' represents H-, an optionally substituted lower alkyl, an optionally substituted cycloalkyl, an optionally substituted acyl, a lower alkyl-C (=NH)-, HO-CO-, an optionally substituted lower alkyl-O-CO-, H2N-CO-, an optionally substituted lower alkyl-HN-CO-, an (optionally substituted lower alkyl)2N-CO-, H2NC(=NH)-, H2NC(=NCN)-, H2NC(=N-CONH2)-, H2NC(=NS(=0)2NH2)-, an optionally substituted lower alkyl-S02- or an optionally substituted heterocyclic group-S02-; R10, Ru, R12 and R13, which may be the same or different, represent H-, or a lower alkyl, and two groups from R10, Rn, R12 and R13 may be combined together to form oxo (0=); A represents a nitrogen-containing saturated heterocyclic group; and, n represents 0,1 or 2, provided that n is zero when A is a nitrogen-containing saturated heterocyclic group other than piperidine group;, or a pharmaceutkaliy acceptable salt thereof. 2.The nitrogen-containing heterocyclic derivative as claimed in claim 1, or a pharmaceuticaily acceptable salt thereof, wherein the nitrogen-containing saturated heterocyclic group shown by symbol A in the formula (I) is a nitrogen- containing saturated monocyclic heterocyclic group or a nitrogen-containing saturated bridged ring. 3. The nitrogen-containing heterocyclic derivative as claimed in claim 2, or a pharmaceuticaily acceptable salt thereof, wherein the nitrogen-containing saturated heterocyclic group shown by symbol A in the formula (I) is a nitrogen- containing saturated monocyclic heterocyclic group. 4. The nitrogen-containing heterocyclic derivative as claimed in claim 3, or a pharmaceutkaliy acceptable salt thereof, wherein the nitrogen-containing saturated heterocyclic group shown by symbol A in the formula (I) is a 6- membered nitrogen-containing saturated monocyclic heterocyclic group. 5. The nitrogen-containing heterocyclic derivative as claimed in any one of claims 1 through 4, or a pharmaceuticaily acceptable salt thereof, wherein symbols R7 and R8 in trie formula (I) above, which may be the same or different, represent H , a lower alkyl, H0-, a lower alkyl-O-, or a halogen. 6. The nitrogen-containing heterocyclic derivative as claimed in any one of claims through 5, or a pharmaceutically acceptable salt thereof, wherein symbol n in the formula (I) is 0. 7. The nitrogen-containing heterocyclic derivative as claimed in any one of claims 1 through 6, or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (I) is H. 8. The nitrogen-containing heterocyclic derivative as claimed in any one of claims 1 through 6, or a pharmaceuticaHy acceptable salt thereof, wherein symbol Rg in the formula (I) is an optionally substituted lower alkyl. 9. The nitrogen-containing heterocyclic derivative as claimed in claim 8 or a prarmaceutically acceptable salt thereof, wherein the substituent in the optionally substituted tower alkyl shown by symbol R9 in the formula (I) is at least one substituted selected from Group a below: Group a (1) a halogen, (2) HO, (3) a lower alkyl-0-, (4) H2N; (5) a lower alkyl-NH-, (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group. 1(\|. The nitrogen-containing heterocyclic derivative as claimed in any one of claims 1 through 6, or a pharmaceuticaHy acceptable salt thereof, wherein symbol R9 n the formula (I) is an optionally substituted acyl. 11.The nitrogen-containing heterocyclic derivative as claimed in claim 10, or a pharmacautically acceptable salt thereof, wherein the optionally substituted acyl shown by symbol R9 in the formula (I) is an optionally substituted lower alkyl- CO-, an optionally substituted cycloalkyl-CO-, an optionally substituted aryl-CO-, an optionally substituted heterocyclic group-CO-or an optionally substituted heterocyclic group-lower alkyl-CO-. 12. The nitrogen-containing heterocyclic derivative as claimed in claim 10 or 11, or a pharmaceutically acceptable salt thereof, wherein the substituent in the optionally substituted acyl shown by symbol R9 in the formula (I) is at least one substitutent selected from the Group b below; Group b (1) HO, (2) a tower alkyl-0-,(3) R101 and R102, which may be the same or different, represent (i) H, (ii) a tower alkyl which may optionally be substituted with HO, a lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a lower alkyl- NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower alkyl)2N-,(iii) an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an aryl which may optionally be substituted with a halogen, (4) a halogen, (5) oxo (0*), (6) a cycloalkyl which may be substituted with R101 and R102N, (7) an aryl, (8) a heterocyclic group, (9) a tower alky I which may optionally be substituted with HO, a tower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which nay optionally be substituted with oxo(0=), (11) H2N-CO-, (12) a tower alkyl- SO2, and (13) a heterocyclic group-SOr- 13. The nitrogen containing heterocyclic derivativer as claimed in any one of claims 1 through 6 or a pharmaceutically acceptable salt thereof, wherein symbol R9 in the formula (1) is H0-0C-, an optionally substituted lower alkyl-0-CO-, HN2CO-. an optionally substituted lower alkyl-NH-CO-, an (optionally substituted lower alkyl)2 N-CO- or an optionally substituted lower alkyl-S-S02. 14.The nitro-gan containing heterocyclic derivative as claimed in claim 1, or a pharmaceutically acceptable salt thereof, which is at least one compound selected from the group consisting of: 4\| (E)-2-{2,6 -dimethy lphenyl)vinyl]quinuclidine, tert-buty14(2E)-3-(2,dimethylphenyl)prop-en-1-yl]piperidine-1darboxylate/ tert-butyH-[(2E)-3K2,64ime1hylphe!iyl)-l-metty catoxylate, tert-buutyl4-[(2E)-3-(2,dimethylrItenyl)prop-2 4 [(E)-2-(2-':hloro-6-methyiphenyl)vinyl]piperidine, 4[Z)-2-(2/6-dimethylphenyl)vinyl]piperldine/ 4[(E)-2-(2,6-dimethylphenyl)vinyl]piperldine, 3 5-dimethyl-4-[(E)-2-piperidin-4-ylvinyl)b€nzonitrile, N ,N, 3,5-teb amethyR-[(E)-2-piperkIin-4-ylvlnyl]aniHne, 2[{E)-2-(2,6-dimethylpnenyl)vinyl]piperidine, 4 [(E)-2-(2,6-dimethylphenyl)vinyl]acepane, 4[(2E)-3-(2f6dlimethylpbenyl)prop-2-en-l-yl]piperidine/ 4 [(2E)-3-{2r6-dimethylphenyl)prop-2-en-yl]piperidina, (2E)-3-(2,6-dimethylphenyl)-l-piperidin-4-ylprop-2-en-i-on8, 3-[(E)-2-(2,6-dimethylphenyl)vinyl]-1-methylpiperidinel 1-benzyl-4-[(E)-2-(2,6-dimtthylphenyl)vinyl]pipe ridintf (2-{4-[(E) -2-(2,6dimethylphenyl)vinyl]piperidln-1 -yl}ethyl)dimethylamine, 5-({4-[(E) -2-(2,6-dimethyIphenyl)vinyl]piperidin-l -yI} carbonyl)-1H-1 ;2,4-triazol- 3-amine, 4-(2-{4-[(E)-2-(2/6-dimethy1-4phenoxyphenyl)vinyt]piptridin-l-y!}-2- oxoethyl)morpholine, l-(2-0-[(E)-2-(2,6dimethylphenyl)vJnyl]plperldin-HI}-2OXOethyl)-4-pyrklin-3- ylcarbonyl)piperine,(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]pipridin-1-yl}-1,1- dimethyl-2-oxoethyl)amine, [l-({4-[(E)-2-(2,6dimethylphenyl)vinyl]piperidin 4-(2-{4-[2E)-3-(2,6-dimethylphenyl)prop-2-en-l-yl]piperidin-l-yl}-2- cxorthyl)morpholine 4-[(E)-2-(2,6dimethylphenyl)vlnyl]-l-[(2S)i)yrolkJln-2-ykarbonyl]piperidin€/ 4-[(E)-2H2r6dimethylphenyl)vinyl]-1-1lH-imklazol-l-ylKeryl)piperidinc, N-(2-{4-[(E)-2-(2/6dimethylphenyl)vinyl]piperidio-l-yl}-2-oxoethyl)oxttane-3- smine, N-{2-[(2-[4-[(E)-2(2/6-dimtthylphenyl)vinyl]piptrid)n-l-yl]-2- oxoethyl)amino]ethyl}acetamide, 2-[(2-{4-[(E)-2-(2/6-dimethylphenyl)vinyl]piperidin-l-yl}-2- oxoethyl)amino]ethanol. l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piridin-l-y}-2-oxoetyhy)Xoethyl)piperidln-2- carboxamkide, l-(2-{4-(E)-2-(2,6-dimethytphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-3^- dimethylpiperidlne, 4[(E)-2-(2,6-dimethyiphenyl)vinyl]-l-[(4-pyrolidin-l-ylpiperidin-i- y)acetyl]piperidine, 4(2-{4-[(E)-2,2,dimtmylphenyl)vinrl]plperidin-l-yl}-2-xoethy!)morpho!lne [4(2M4-[(fi)-2-(2,dimethylphenyl)vinyl]piptrk}in-l-yl}-2-xc)ethyl)morpholine- 2-yl]methanol, 4-(2-{4-[(E)-2-(2,dimethylphenyl)vinyl]piperidln-l-yl}-2'OXoethyl)-l,4- oxazepane, H2M4-[(E)-2K2,dim«thylphenyl)viny1)piperidin-1-yl}-2-oxoethyl)pipe carboxamkie, [(2R)-4-(2 {4-[(E)-2-(2,6-dimethylphenyl)vinyi]piperidin-1-yl}-2- oxoethyl)morpholin-2-yl]methanolo, (2R)-l-(2-{4-[(E)-2-(2.6-dimethYlphtnYl)vinyl]piperidln-l-yU-2- oxoethyi)piptridine -2-carboxamkfe, (2S)-l-(2-{4-[(E)-2-{2f6-dlmtthylphtnyI)vinyl3plptrldin-l-yl}-2- oxoethyl)piper Wine -2-carboxamfcte, [(2S)-4-(2"{4-[(E)-2-(2,6-dimcthylphenyl)v»nyl]piper»din-l-yl}-2- oxoethyl)morpholin-2-yl]mtttonol, [(3R)-l-(2-{4-[(E)-2-(2,6-dimelhylphenyl)vinyl3piperldin-l-yl}-2- oxoethyl)piperKlin-3irl)methanol, [(3S)-1-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1-yl}-2- oixoethyl]piperidin-3-yl]methanol, (2R)-2-({4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-ylKarbonyl-l- Methylpiperidine, 4-[(E)-2(2,6-dimtthylphtnyl)yinyl]-l-Oixolylpiptrkiint, (3S)-l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyi]piperldin-l-yl}-2- oxoethy!)pipefidin-3-ol, (3R)-N-2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-N- methytetrahydrofuran-3-amine, (35)-N-2-{(E)-2-(2,6-dimethylphenyl)vinyl]pip€ridin-l-yl}-2-oxoethyl)-N- methyltttrahydrofuren-3-emint, l-(2-0-[(E)-2K2,6-Dimethylphenyl]Ylnyl]piperkiin-l-yl}-2-oxoethyl)piperidin€-4- amine, 1-(2-{4-[(E)-2-(2,6-Dimtthylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)pip•rzin•/ (lMR)-2(2-{4-[(E)-2-(2,6-dimethylphenyl)vlnyl]piperidin-l-yl}-2-xoethy0-2,5- (Ii,i23bicycb [2,2,1] heptane, and l2-{4-[(E)-2H2,6dimethylphenyl)vinyl]piperdin-1-yl}-2-ox)XMthyl)methyl[(3R)- ie trahydrofur an-3-yI]amine. 15. A pharmaceutical composition comprising the nitrogen-containing heterocyclic derivative as claimed in any one of claims 1 through 14, or a pharmaceutically acceptable salt thereof. 16. A pharmaceutical composition, which is a sodium channel inhibitor comprising a nitrogen-containing heterocyclic derivative represented by formula (II) below: (wherein symbols in formula (II) above have the following significance: R1and R2, which may be me same or different, represent H-, an optionally substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower elkyl-O- CO ,H2N-C0-, a lower alkyl-HN-CO-, a (lower alkyl)2N-C0-,H0-, a lower alkyl-0-, an aryl-O-, an acyl-O-, H2N-, a lower afcyl-HN-, a (tower alkyl)2N-, an acyl-NH-,a halogen, nitro, a heterocyclic group, or cyano; R3 and R4, which may be the same or different, represent an optionally substituted lower alkyl, a cycioalkyl, an acyl, HO-CO-, a lower akyl-O-CO-, H2N- C0- , a lower akyl-HN-CO-, 2 (lower alkyl)2N-CO-, HO-, a tower alkyl-O-, an acyl-0-, H2N-, a lower alkyl-HN-, a (tower alkyl)2 N-, an acyl-NH-, a halogen, nitro, or cyano; R5 and R6, which may be the same or different, represent H-, a lower alkyl, or halogen; R7 and R8, which may be the same or different, represent H-, a tower alkyl, HO-, a tower afcyl-O-, or a halogen; R7 and R8 may be combined together to form oxo (0«); R9 represents H-, an optionally substituted tower alkyl, an optionally substituted cyctoakyl, an optionally substituted acyl, a lower alkyl-C(=NH)-, HO-CO-, an optionally substituted tower alkyl-0-CO-, H2N-CO-, an optionally substituted tower alkyl -HN-CO-, an (optionally substituted tower aklyl)2N-CO-, H2NC(=NH)- -82- /H2NC)-H2NC(=NS(=0)2NH2)-/ an optionally substituted towewr alkyl-SO2- or opotionally substituted heterocyclic group-SO1-; Ri0, R11, R12 and R13 which may be the same or different, represent H-, or a tower alkyl, and two groups from R10, R11, R12 and R13 may be combined together to form. oxo (0=); A represents a nitrogen-containing saturated heterocyclic group, quinolyi or pyrklin-4-yl; provided that when A represents quinolyi or pyridin-4-yl, R9 is absent; and, n represents 0,1 or 2), or a pharmaceutically acceptable salt thereof. 17 The pharmaceutical composition as claimed in claim 15 or 16, which is a therapeutic agent for neuropathic pain. 18 The pharmaceutical composition as claimed in claim 17 which is a therapeutic agent for diabetic neuropathic pain. The invention provides a novel nitrogen-containing heterocyclic derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof, and a pharmaceutical composition comprising the nitrogen-containing heterocyclic derivative and a pharmaceutically acceptable salt thereof, in particular, a pharmaceutical composition effective as a sodium channel inhibitor, having an excellent analgesic action especially on neuropathic pain with minimized side effects.

Full Text

TECHNICAL FIELD
The present invention relates to a novel nitrogen-containing heterocyclic
derivative having 2,6-disubstituted styryl and a pharmaceutically acceptable salt
thereof. The present invention further relates to a pharmaceutical composition
comprising a novel nitrogen-containing heterocyclic derivative having
2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof and more
particularly, to a pharmaceutical composition having an analgesic action especially
on neuropathic pain which acts as a sodium channel inhibitor.
BACKGROUND ART
A voltage-dependent sodium channel is a protein responsible for the
initiation and propagation of action potentials in neurons. The voltage-dependent
sodium channel is composed of one larger a subunit with four domains, each
consisting of six transmembrane segments, as a common structure and two smaller P
subunits. A maIor part of the channel function is played by a subunit. To date, more
than 10 different a subunit subtypes have been known(Goldin AL, Annals of the
New York Academy of Sciences 868:38-50, 1999). Each voltage-dependent sodium
channel subtype shows distinct distributions in the central and peripheral nerve
tissues. These subtypes regulate neural excitability and play an important role in
regulating physiological functions in individual tissues. It is also suggested that they
are deeply associated with various pathological conditions (Goldin AL, Annual
Review of Physiology 63:871-894, 2001).
In recent years, it has become clear that voltage-dependent sodium channels
are deeply involved in neural transmission of pain, and sodium channel blockers are
expected to be excellent pain therapeutics, especially neuropathic pain therapeutics
(Taylor CP, Current Pharmaceutical Design 2: 375-388, 1996).
Neuropathic pain means a pain that results from dysfunction in the central or
peripheral neurons and refers to diabetic neuropathic pain, cancer pain, trigeminal
neuralgia, phantom limb, post herpetic neuralgia, thalamic pain, etc. The clinical
picture of neuropathic pain includes stabbing pain, burning pain, hyperalgesia,

allodynia, etc.
In medical scenes, non-steroidal anti-inflammatory drugs, narcotic
analgesics such as morphine, etc. are used for the purpose of relieving pain. Recently,
antiarrhythmic drugs and anticonvulsants, which are sodium channel blockers, have
come to be used as well, for the purpose of relieving pain.
The non-steroidal anti-inflammatory drugs are not completely satisfied in
terms of analgesic actions and involve the problem of side effects such as
gastrointestinal disturbance or renal disorder. The narcotic analgesics such as
morphine are effective for nociceptive pain, but encounter serious side effects on the
alimentary, respiratory or central nervous system. In addition, these drugs are
generally less effective for neuropathic pain.
The antiarrhythmic drugs such as lidocaine or mexiletine and the
anticonvulsants such as carbamazepine, which are sodium channel blockers, have
come to be used to relieve pain. Mexiletine has been approved and is available as an
anti-diabetic neuropathic pain drug. However, these sodium channel blockers involve
problems that they have central side effects such as convulsions or drowsiness, or
peripheral side effects such as bradycardia and hence, have difficulty to increase a
dose to a sufficient level, resulting in failure to achieve satisfactory analgesic effects.
As above, analgesics that are useful for the treatment of neuropathic pain
and are excellent in safety have not been found yet. Accordingly, sodium channel
blockers having an excellent analgesic action especially on neuropathic pain with
minimized side effects have been desired.
Lidocaine, mexiletine, carbamazepine, etc. mentioned above are reported
but do not fall under nitrogen-containing heterocyclic derivatives having styryl
group.
Derivatives having a 1-pyridylalkylpiperidine as a basic skeleton are
disclosed and have a sodium channel inhibitory activity (Patent Literature 1). In this
literature, compounds having 2-cyclohexylmethyloxy-6-fluorophenylethenyl on the
piperidine ring as a substituent are disclosed.
Also, compounds containing a mono-substituted phenylethenyl having a
halogen or cyclohexylmethyloxy at the 2- or 3-position of a 1-aromatic heterocyclic
group-alkylpiperidine ring as a substituent are described (Patent Literature 2).
On the other hand, compounds, not as sodium inhibitors but as metabotropic
glutamate receptor (mGluR) inhibitors and analgesics, which are one of therapeutics
for various diseases, based on mGluR inhibitory effects are disclosed (Patent

Literatures 3 - 4). Specifically, there are described 2-pyridine compounds having
styryl group (Patent Literature 3), thiazole, oxazole, 1,2,4-thiadiazole,
1,2,4-oxadiazole, lH-l,2,4-triazole, 2-oxo-l,3,4-oxathiazole, 2H-tetrazole,
2-pyridine, pyridinium, pirazine, indolinium, benzothiophene, benzothiazonium,
quinoline or quinolium compounds having styryl group (Patent Literature 4),
imidazole compounds having styryl group (Patent Literature 5), and imidazole,
1.2,4-triazole or 2H-tetrazole compounds having styryl group (Patent Literature 6),
but these compounds are unsaturated heterocyclic compounds having styryl group.
Furthermore, piperidine compounds having benzyl or phenylmethylene
based on NMDA/NR2B antagonizing effect are disclosed (Patent Literature 7).
On the other hand, nitrogen-containing heterocyclic derivatives having
styryl group, which are formed by combining groups, are disclosed (Patent
Literatures 8 and 9) and among these derivatives, only the compounds that phenyl
group and a nitrogen-containing heterocyclic ring are combined via a -O-lower
alkylene-(Patent Literature 3), a -S-lower alkylene- or a -lower alkylene-C(0)0- are
specifically disclosed (Patent Literature 4) but nitrogen-containing heterocyclic
derivatives are neither disclosed specifically nor even suggested. Moreover, these
derivatives are used as calcium channel antagonists (Patent Literature 8) or for
promotion of acetylcholine release (Patent Literature 9) but nothing is disclosed or
even suggested on any sodium channel inhibitory activity or any analgesic action.
Patent Literature 1
European Patent Publication No. 1254904
Patent Literature 2
WO03/84948 Pamphlet
Patent Literature 3
WO99/02497 Pamphlet
Patent Literature 4
WO01/16121 Pamphlet
Patent Literature 5
WO02/46166 Pamphlet
Patent Literature 6
WO99/08678 Pamphlet
Patent Literature 7
WOO 1/32615 Pamphlet
Patent Litera+ture 8

W094/13291 Pamphlet
Patent Literature 9
W097/19059 Pamphlet
DISCLOSURE OF THE INVENTION
An obIect of the present invention is to provide a novel nitrogen-containing
heterocyclic derivative having 2,6-disubstituted styryl or a pharmaceutically
acceptable salt thereof.
Another obIect of the present invention is to provide a pharmaceutical
composition, especially a pharmaceutical composition for a sodium channel inhibitor,
which has a remarkable analgesic action on neuropathic pain, comprising the
nitrogen-containing heterocyclic derivatives having 2,6-disubstituted styryl or a
pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier.
The present inventors made extensive studies on nitrogen-containing
heterocyclic derivatives to achieve the foregoing obIects and as a result, have found
that derivatives containing a nitrogen-containing hetero ring having 2,6-disubstituted
styryl as a basic skeleton or salts thereof possess a potent inhibitory activity against
sodium channel and exert an action on mice with streptozotocin-induced diabetic
neuropathy as disease animal models, and have accomplished the present invention,
which is useful for neuropathic pain drugs.
That is, the present invention relates to the nitrogen-containing heterocyclic
derivatives represented by formula (I) below. The nitrogen-containing heterocyclic
derivatives of the present invention are characterized in comprising styryl group
always having two substituents at the ortho-position, namely, 2,6-disubstituted styryl
group, and a nitrogen-containing heterocyclic group.
This styryl group may optionally have an additional substituent(s). In the
nitrogen-containing heterocyclic derivatives, saturated nitrogen-containing
heterocyclic derivatives are preferred.
Specifically, the present invention provides the following
nitrogen-containing heterocyclic derivatives or pharmaceutically acceptable salts
thereof, pharmaceutical compositions comprising these compounds and
pharmaceutically acceptable carriers, use of these compounds, a method for treating
diseases mediated by sodium channel, a method for treating neuropathic pain, and a
method for treating diabetic neuropathic pain.
[l A nitrogen-containing heterocyclic derivative represented by formula (I)

5 (wherein symbols in formula (I) above have the following significance:
R1 and R2, which may be the same or different, represent H-, an optionally
substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower alkyl-O-CO-,
HaN-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an
aryl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a
10 halogen, nitro, a heterocyclic group, or cyano;
R3 and R4, which may be the same or different, represent an optionally
substituted lower alkyl, a cycloalkyl, an acyl, HO-CO-, a lower alkyl-O-CO-,
H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an
acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a halogen, nitro,
15 or cyano;
R5 and R6, which may be the same or different, represent H-, a lower alkyl,
or a halogen;
R7 and R8, which may be the same or different, represent H-, a lower alkyl,
HO- a lower alkyl-O-, or a halogen;
2Q R7 and R8 may be combined together to form oxo (0=);
R9 represents H-, an optionally substituted lower alkyl, an optionally
substituted cycloalkyl, an optionally substituted acyl, a lower alkyl-C (=NH)-,
HO-CO-, an optionally substituted lower alkyl-O-CO-, H2N-CO-, an optionally
substituted lower alkyl-HN-CO-, an (optionally substituted lower alkyl)2N-CO-,
25 H2NC(=NH)-, H2NC(=NCN)-, H2NC(=N-CONH2), H2NC(=NS(=0)2NH2)-,
an optionally substituted lower alkyl-S02- or an optionally substituted heterocyclic
group-S02-;
R10, R11, R12 and R13, which may be the same or different, represent H-, or a
lower alkyl, and two groups from R10, R11, R12 and R13 may be combined together to
30 form oxo (0=);
A represents a nitrogen-containing heterocyclic group, quinolyl or
pyrtdin-4-yl;

provided that when A represents quinolyl or pyridin-4-yl, R9 is absent; and,
n represents 0, 1, or 2), or a pharmaceutically acceptable salt thereof.
12] The nitrogen-containing heterocyclic derivative according to [1], or a
pharmaceutically acceptable salt thereof, wherein the nitrogen-containing
heterocyclic group shown by symbol A in the formula (I) is a nitrogen-containing
saturated monocyclic heterocyclic group or a nitrogen-containing saturated bridged
ring.
13] The nitrogen-containing heterocyclic derivative according to [2], or a
pharmaceutically acceptable salt thereof, wherein the nitrogen-containing
heterocyclic group shown by symbol A in the formula (I) is a nitrogen-containing
saturated monocyclic heterocyclic group.
[4] The nitrogen-containing heterocyclic derivative according to [3], or a
pharmaceutically acceptable salt thereof, wherein the nitrogen-containing
heterocyclic group shown by symbol A in the formula (I) is a 6-membered nitrogen-
containing saturated monocyclic heterocyclic group.
In the nitrogen-containing heterocyclic derivatives or pharmaceutically
acceptable salts thereof according to [1] to [4], preferably the nitrogen-containing
saturated heterocyclic group shown by symbol A in the formula (I) is piperidine.
[5] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [4], or a pharmaceutically acceptable salt thereof, wherein symbols R7
and R8 in the formula (I) above, which may be the same or different, represent H-, a
lower alkyl, HO-, a lower alkyl-O-, or a halogen.
[6] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [5], or a pharmaceutically acceptable salt thereof, wherein symbol n in
the formula (I) is 0.
[7] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in
the formula (I) is H.
18] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in
the formula (I) is an optionally substituted lower alkyl.
19] The nitrogen-containing heterocyclic derivative according to [8], or a
pharmaceutically acceptable salt thereof, wherein the substituent in the optionally
substituted lower alkyl shown by symbol R9 in the formula (I) is at least one
substituent selected from Group a below:

Group a: (1) a halogen, (2) HO, (3) a lower alkyl-O-, (4) H2N, (5) a lower
alkyl-NH-. (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group; this
heterocyclic group is preferably a monocyclic heterocyclic group.
[10] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in
the formula (I) is an optionally substituted acyl.
[11] The nitrogen-containing heterocyclic derivative according to [10], or a
pharmaceutically acceptable salt thereof, wherein the optionally substituted acyl
shown by symbol R9 in the formula (I) is an optionally substituted lower alkyl-CO-,
an optionally substituted cycloalkyl-CO-, an optionally substituted aryl-CO-, an
optionally substituted heterocyclic group-CO- or an optionally substituted
heterocyclic group-lower alkyl-CO-.
[1.2] The nitrogen-containing heterocyclic derivative according to [10] or
[11], or a pharmaceutically acceptable salt thereof, wherein the substituent in the
optionally substituted acyl shown by symbol R9 in the formula (I) is at least one
substituent selected from Group b below:
Group b: (1) HO, (2) a lower alkyl-O-, (3) R101R102N (wherein R101 and R102,
which may be the same or different, represent (i) H, (ii) a lower alkyl which may
optionally be substituted with HO, a lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a
lower alkyl-NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower
alkyl)2N-, (iii) an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an
aryl which may optionally be substituted with a halogen), (4) a halogen, (5) oxo (0=),
(6)a cycloalkyl which may be optionally substituted with R101R102N, (7) an aryl, (8)a
heterocyclic group, (9) a lower alkyl which may optionally be substituted with HO, a
lower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which may
optionally be substituted with oxo (0=), (ll)H2N-CO-, (12) a lower alkyl-S02-, and
Q 3) a heterocyclic group-S02-.
[13] The nitrogen-containing heterocyclic derivative according to any one of
[1] through [6], or a pharmaceutically acceptable salt thereof, wherein symbol R9 in
the formula (I) is HO-OC-, an optionally substituted lower alkyl-O-CO-, H2N-CO-,
an optionally substituted lower alkyl-NH-CO-, an (optionally substituted lower
alkyl)2N-CO- or an optionally substituted lower alkyl-S02-.
In the nitrogen-containing heterocyclic derivatives or pharmaceutically
acceptable salts thereof according to any one of [1] through [13], symbols R4 and R5

in the formula (I) above are more preferably a lower alkyl, and most preferably, these
R4 and R5 are methyl group.
[4] The nitrogen-containing heterocyclic derivative according to [1], or a
pharmaceutically acceptable salt thereof, which is at least one compound selected
from the group consisting of:
4-[(E)-2-(2,6-dimethylphenyl)vinyl]quinuclidine,
4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine,
4-[(Z)-2-(2,6-dimethylphenyl)vinyl]piperidine,
4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine,
3,5-dimethyl-4-[(E)-2-piperidin-4-ylvinyl]benzonitrile,
N,N,3,5-tetramethyl-4-[(E)-2-piperidin-4-ylvinyl]aniline,
2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine,
4-[(E)-2-(2,6-dimethylphenyl)vinyl]azepane,
4-[(2E)-3-(2,6-dimethylphenyl)prop-2-en-l-yl]piperidine,
3 -[(E)-2- (2,6-dimethylphenyl)vinyl]-1 -methylpiperidine,
l-benzyl-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine,
(2-{4-[(Ii)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}ethyl)dimethylamine,
5-({4-[0i)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}carbonyl)-lH-l,2,4-triazol-3-
amine,
4-(2-{4-[(E)-2-(2,6-dimethyl-4-phenoxyphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)
morpholine,
4-(2-{2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine,
l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-4-(pyridin-3-
ylcarbonyl)piperazine,
(2- {4-[(E)-2-(2,6-dimethylphenyl)viny l]piperidin-1 -yl} -1,1 -dimethyl-2-oxoethyl)
amine,
[ 1 -({4-| (E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} carbonyl)cy clobutyl] amine,
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-[(2S)-pyrolidin-2-ylcarbonyl]piperidine,
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(lH-imidazol-1 -ylacetyl)piperidine,
N-(2- { 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)oxetane-3 -
amine,
N-{2-[(2-[4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl]-2-oxoethyl)amino]
ethyl} acetamide,
2-[(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)amino]ethanol,
1 -(2- {4-[(E)-2-(2,6-dimethy lphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)piperidine-

2-carboxamide,
l-(2-{4-(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-3,5-dimethyl
piperidine,
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-[(4-pyrolidin-l-ylpiperidin-l-yl)acetyl]
piperidine,
4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine,
[4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)morpholine-2-
yl] methanol,
4-(2- {4- [(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)-1,4-oxazepane,
l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)piperidine-4-
amine,
1 -(2- {4- [ (E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} -2-oxoethyl)piperazine,
(lR,4R)-2-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-2,5-
diazabicyclo[2.2.1]heptane, and,
(2-{4-[(E)-2-(2I6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)methyl[(3R)-
tetrahyd rofuran-3 -yl] amine.
[15] A pharmaceutical composition comprising the nitrogen-containing
heterocyclic derivative according to any one of [1] through [14], or a
pharmaceutically acceptable salt thereof, and a pharmaceutically acceptable carrier.
[16] The pharmaceutical composition according to [15], which is a sodium
channel inhibitor.
[17] The pharmaceutical composition according to [15] or [16], which is a
therapeutic agent for neuropathic pain.
[18] The pharmaceutical composition according to [17], which is a
therapeutic agent for diabetic neuropathic pain.
[19] Use of the nitrogen-containing heterocyclic derivative according to any
one of [1] through [14], or a pharmaceutically acceptable salt thereof, to manufacture
a pharmaceutical composition.
[20] Use of the nitrogen-containing heterocyclic derivative according to [19],
or a pharmaceutically acceptable salt thereof, to manufacture a therapeutic agent for
neuropathic pain.
[21] Use of the nitrogen-containing heterocyclic derivative according to [20],
or a pharmaceutically acceptable salt thereof, to manufacture a therapeutic agent for
diabetic neuropathic pain.
[22] A method for treating a disease caused by sodium channel, which

comprises administering to a patient a therapeutically effective dose of the
nitrogen-containing heterocyclic derivative according to any one of [1] through [12],
or a pharmaceutically acceptable salt thereof.
[23] A method for treating neuropathic pain, which comprises administering
to a patient a therapeutically effective dose of the nitrogen-containing heterocyclic
derivative according to [22], or a pharmaceutically acceptable salt thereof.
[24] A method for treating diabetic neuropathic pain, which comprises
administering to a patient a therapeutically effective dose of the nitrogen-containing
heterocyclic derivative according to [23], or a pharmaceutically acceptable salt
thereof.
BEST MODE FOR CARRYING OUT THE INVENTION
The compounds of the present invention represented by formula (I)
(hereinafter sometimes merely referred to as "Compound (I) of the present
invention") will be described below in detail.
[Definition, etc.]
In the definitions of the structural formulae in the specification, the term
"lower" is used to mean a straight or branched carbon chain having the carbon
number of 1 to 6, unless otherwise indicated.
Examples of The "lower alkyl", for example, is used to mean methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl,
tert-pentyl, hexyl, isohexyl, and the like, preferably, methyl, ethyl, propyl, butyl and
tert-butyl
The "lower alkenyl" is used to mean a hydrocarbon group having at least
one double bond and includes, for example, vinyl, propenyl, allyl, isopropenyl,
hexenyl, and the like.
The "lower alkynyl" is used to mean a hydrocarbon group having at least
one triple bond and includes, for example, ethynyl, propynyl, butynyl, and the like.
The "cycloalkyl" is used to mean a 1- to 3-ring aliphatic saturated
hydrocarbon group having the carbon number of 3 to 14 and includes, for example,
cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl,
bicycloheptyl, bicyclooctyl, bicyclononyl, bicyclodecanyl, tricyclononyl,
tricyclodecanyl, tricycloundecanyl, tricyclododecanyl, bicyclo[2.2.1]heptyl,
bicyclo[2 2.2]octyl, and the like, preferably, cyclopropyl, cyclobutyl, cyclopentyl,
cyclohexyl, cycloheptyl and cyclooctyl.

The "aryl" is used to mean a 1- to 3-ring aromatic hydrocarbon group having
the carbon number of 6 to 14, in which a cycloalkyl may optionally be fused to a
phenyl. The aryl includes, for example, phenyl, indenyl, naphthyl, anthryl,
phenanthryl, indanyl, tetrahydronaphthyl, and the like, preferably, phenyl and
naphthyl.
The "heterocyclic group" is used to mean a 4- to 16-membered monocyclic,
bicyclic or tricyclic saturated or unsaturated ring containing 1 to 4 hetero atoms
selected from N, S and O. This heterocyclic group may optionally be bridged or may
optionally take a spiro form. The unsaturated ring includes an aromatic ring (hetero
aryl) and a non-aromatic ring. The monocyclic group includes azetidinyl, oxetanyl,
pyrrolidinyl, tetrahydrofuranyl, 1,3-dioxoranyl, tetrahydro-2H-pyranyl, pyrazolidinyl,
piperazinyl, piperidinyl, morpholinyl, thiomorpholinyl, 1,4-oxazepanyl, trithianyl,
dioxoranyl, furyl, thienyl, pyrrolyl, 2,5-dihydro-lH-pyrrol-l-yl, imidazolyl,
pyrazolyl, thiazolyl, oxazolyl, pyridyl, pirazinyl, pyrimidyl, triazolyl, thiadiazolyl,
pyridazinyl, triazinyl, tetrahydropyranyl, oxadiazolyl, and the like; the bicyclic group
includes indolinyl, isoindolinyl, 3, 4-methylenedioxyphenyl, 3,
4-ethylenedioxyphenyl, benzofuranyl, benzothienyl, benzothiadiazolyl,
benzothiazolyl, benzimidazolyl, indolyl, 2,3-dihydroindolyl, quinolyl, isoquinolyl,
1,2,3,4-tetrahydroquinolyl, decahydroquinolyl, 1,2,3,4-tetrahydroisoquinolyl,
decahydroisoquinolyl, quinoxalinyl, and the like; and the tricyclic group includes
carbazolyl, acridinyl, phenothiadinyl, and the like. The bridged heterocyclic group
includes quinuclidinyl, 2,5-diazabicyclo[2.2.1]heptyl, 8-azabicyclo[3.2.1]octyl,
7-azabicyclo[2.2. l]heptyl, and the like. The spiro-heterocyclic group includes
l,4-dioxa-8-azaspiro[4.5]decanyl, and the like.
The "nitrogen-containing hetero-aryl" is used to mean a 4- to 10-membered
mono- or bicyclic nitrogen-containing hetero-aryl having 1 to 3 nitrogen atoms in the
heterocyclic groups described above and includes, for example, pyrrolyl, imidazolyl,
pyrazolyl, triazolyl, tetrazolyl, pyridyl, pyridazyl, pyrimidyl, pyrazyl, triazyl, indolyl,
isoindolyl, benzimidazolyl, benzopyrazolyl, pyrrolopyridyl, imidazopyridyl, quinolyl,
isoquinolyl, quinoxalyl, and the like, preferably, imidazolyl, pyridyl and quinolyl.
The "nitrogen-containing saturated heterocyclic group " is used to mean a 3-
to 10-membered mono- or bicyclic nitrogen-containing heterocycloalkyl having 1 to
3 nitrogen atoms in the heterocyclic groups described above and includes, for
example, aziridinyl, azetidinyl, pyrrolidyl, piperidyl, piperazyl, morpholinyl,
hexahydroazepinyl, 1,4-diazepinyl, 1,4-oxazepinyl, quinuclidinyl,

2,5-diazabicyclo[2.2.1]heptane, azabicyclooctyl (e.g., azabicyclo[3.2.1]octyl),
diazabicyclooctyl, azabicyclononyl, azabicyclodecanyl,
l,4-dioxa-8-azaspiro[4.5]decanyl, and the like, preferably, pyrrolidyl, piperidyl,
piperazyl, morpholinyl, hexahydroazepinyl, 1,4-diazepinyl, 1,4-oxazepinyl,
quinuclidinyl, 2,5-diazabicyclo[2.2.1]heptane and azabicyclo[3.2.1]octyl.
The "nitrogen-containing heterocyclic group" is used to mean the
nitrogen-containing hetero-aryl described above, the nitrogen-containing saturated
heterocyclic group described above, or a group formed by fusing the
nitrogen-containing heterocyclic group or the nitrogen-containing hetero-aryl and the
nitrogen-containing heterocycloalkyl, and preferably means pyrrolidyl, piperidyl,
morpholinyl, hexahydroazepinyl, azabicyclo[3.2.1]octyl,
l,4-dioxa-8-azaspiro[4.5]decanyl, imidazolyl, pyridyl and quinolyl.
The "acyl" includes HCO-, a lower alkyl-CO-, a lower alkenyl-CO-, a
cycloalkyl-CO-, aryl-CO-, a heterocyclic group-CO-, a heterocyclic group-lower
alkyl-CO-, a heterocyclic group-lower alkenyl-CO-, a heterocyclic group-lower
alkynyl-CO-, a lower alkyl-CS-, a lower alkenyl-CS-, a cycloalkyl-CS-, an aryl-CS-,
heterocyclic group-CS-, a heterocyclic group-lower alkyl-CS-, a heterocyclic
group-lower alkenyl-CS- and a heterocyclic group-lower alkynyl-CS-. Preferably, the
acyl is a lower alkyl-CO-, a cycloalkyl-CO-, an aryl-CO-, a heterocyclic group-CO-
and a heterocyclic group-lower alkyl-CO-. This heterocyclic group-CO- is more
preferably a monocyclic heterocyclic group-CO-. Specific examples are HCO-,
acetyl, propionyl, cyclopropylcarbonyl, cyclobutylcarbonyl, cyclopentylcarbonyl,
cyclohexylcarbonyl, azetidin-2-ylcarbonyl,
2,5-dihydro-lH-pyrrol-l-ylmethylcarbonyl, pyrolidin-2-ylcarbonyl,
pyrolidin-1 -ylmethylcarbonyl, piperidin-2-ylcarbonyl, piperidin-3-ylcarbonyl,
piperidm-4-ylcarbonyl, morphoIin-2-ylcarbonyl, morpholin-3-ylcarbonyl,
morpholin-4-ylmethylcarbonyl, 1,4-oxazepan-4-yl-carbonyl,
l,4-oxazepan-4-yl-methylcarbonyl, piperidin-1-ylmethylcarbonyl, benzoyl,
imidazol-4-ylcarbonyl, imidazol-1 -ylmethylcarbonyl, l,2,4-triazol-2-ylcarbonyl,
pyridin-2-ylcarbonyl, nicotinoyl, pyridin-2-ylmethylcarbonyl, isonicotinoyl,
benzimidazol-5-ylcarbonyl, thenoyl, pyrrolidinylcarbonyl, piperidinylcarbonyl,
2,5-diazabicyclo[2.2. l]heptan-l-ylmethylcarbonyl, etc.
The "halogen" includes fluoro, chloro, bromo and iodo, preferably, fluoro
and chloro.
The substituent in the "optionally substituted lower alky!" and " optionally

substituted cycloalkyl" includes at least one member selected from Group a. The
substituent in the "optionally substituted acyl," "optionally substituted lower
alkyl-S02-" and "optionally substituted heterocyclic group-So2-" includes at least
one member selected from Group b.
Group a: (1) halogen, (2) HO, (3) a lower alkyl-O-, (4) H2N, (5) a lower
alkyl-NH-, (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group; this
heterocyclic group is preferably a monocyclic heterocyclic group.
Group b: (1) HO, (2) a lower alkyl-O-, (3) R101R102N (wherein R101 and R102,
which may be the same or different, represent (i) H, (ii) a lower alkyl which may
optionally be substituted with HO, lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a
lower alkyl-NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower
alkyl)2N-, (iii) an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an
aryl which may optionally be substituted with a halogen), (4) a halogen, (5) oxo (0=),
(6)a cycloalkyl may optionally be substituted with R101R102N, (7)an aryl, (8)a
heterocyclic group, (9) a lower alkyl which may optionally be substituted with HO, a
lower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which may
optionally be substituted with oxo (0=), (ll)H2N-CO-, (12) a lower alkyl-S02-, and
(13) a heterocyclic group-S02-.
In Compound (I) of the present invention, optical isomers (enantiomers,
diastereomers, etc.) or geometrical isomers are present depending upon type of
substituents. Consequently, Compound (I) of the present invention includes these
optical isomers or geometrical isomers, either in the isolated form or as mixtures
thereof.
Compound (I) of the present invention may form a salt with an acid addition
salt or with a base. Specific examples of such acid addition salts with an inorganic
acid such as hydrochloric acid, hydrobromic acid, hydroiodic acid, sulfuric acid,
nitric acid, phosphoric acid, etc.; with an organic acid such as formic acid, acetic acid,
propionic acid, oxalic acid, malonic acid, succinic acid, fumaric acid, maleic acid,
lactic acid, malic acid, citric acid, tartaric acid, carbonic acid, picric acid,
methanesulfonic acid, ethanesulfonic acid, glutamic acid, etc.; with an inorganic base
such as sodium, potassium, magnesium, calcium, aluminum, etc., an organic base
such as methylamine, ethylamine, monoethanolamine, diethanolamine,
triethanolamine, cyclohexylamine, lysine, ornithine, etc. In addition, Compound (I)
of the present invention or its pharmaceutically acceptable salts may form hydrates,
solvates with ethanol, etc. or polymorphism.

Furthermore, Compound (I) of the present invention includes all of so-called
prodrugs, i.e., the compounds which can be metabolized in vivo and converted into
Compound (I) of the present invention or its pharmaceutically acceptable salts.
Examples of the group which forms the prodrugs of Compound (I) of the present
invention are those described in Prog. Med. 5: 2157-2161 (1985) and those described
in "Iyakuhin no Kaihatsu" (Development of Pharmaceuticals) published in 1990 by
Hirokawa Shoten, Vol. 7, "Molecular Design", pages 163-198. Specifically, the group
is a group, which can be converted into the primary amine or secondary amine, HO-,
HO-CO-, etc. defined in the present invention, by hydrolysis or solvolysis or under
physiological conditions. The prodrugs of HO- include, for example, an optionally
substituted lower alkyl-COO-, an optionally substituted aryl-CO-O-,
RO-CO-optionally substituted lower alkylene-CO-O- (wherein R represents H- or a
lower alkyl; hereinafter the same), RO-CO-optionally substituted lower
alkenylene-CO-O-, a RO-CO-lower alkylene-O-lower alkylene-CO-O-,
RO-CO-CO-0-, ROS(=0)2-optionally substituted lower alkenylene-CO-O-,
phthalidyl-O-, 5-methyl-l,3-dioxolen-2-on-4-yl-methyloxy, etc.
[Processes for Production]
Compound (I) of the present invention can be produced by applying a
variety of synthesis techniques, using the characteristics based on its basic skeleton
or type of substituents. Hereinafter, representative processes are described below.
PROCESS 1:

(wherein A, R1 - R13 and n have the same significance as defined above; hereinafter
the same).
Compound (la) of the present invention can be obtained by the Wittig
reaction (Org. React., 14, 270-490 (1965)) of a phosphonium salt (II) with an

aldehyde or ketone (III) in a conventional manner. A reaction solvent, which can be
used, includes a solvent inert to this reaction, such as tetrahydrofuran, dioxane,
dimethylformamide, dimethylsulfoxide, toluene, etc. As a base, there may be used
sodium hydride, potassium tert-butoxide, sodium ethoxide, lithium diisopropylamide,
etc. The reaction can be carried out under the conditions of cooling (e.g., -70°C) to
heating.
PROCESS 2:

Compound (lb) of the present invention can be obtained by the aldol
condensation (Org. React., 16,1-438 (1968)) of an aldehyde (TV) with a (V) in a
conventional manner. A reaction solvent, which can be used, includes a solvent inert
to this reaction, such as tetrahydrofuran, dioxane, dimethylformamide,
dimethylsulfoxide, toluene, etc. The reaction may be carried out under basic
conditions and in this case, sodium hydride, potassium tert-butoxide, sodium
ethoxide, lithium diisopropylamide, lithium bis(trimethylsilyl)amide, etc. may be
used. As an acid used when the reaction is carried out under acidic conditions, there
may be used hydrochloric acid, trifluoroacetic acid, tosylic acid, boron trifluoride,
aluminum trichloride, titanium tetrachloride, etc. The reaction can be carried out
under the conditions of cooling (e.g., -70°C)to heating.

(wherein M represents Li, MgCl, etc.; hereinafter the same).
Compound (Ic) of the present invention can be obtained by the reaction of
an aryl metal such as an aryl lithium, an aryl Grignard, etc. with a carbonyl

compound in a conventional manner (Org. Synth. HI, 200 (1955); Org. React., 6,
339-366 (1964); Org. React., 8, 258-304 (1967)). A reaction solvent, which can be
used, includes a solvent inert to this reaction, such as diethyl ether, tetrahydrofuran,
dioxane, dimethylsulfoxide, toluene, etc. The reaction can be carried out under the
conditions of cooling (e.g., -70°C) to heating.
In addition to the processes described above, Compound (I) of the present
invention can also be obtained, e.g., by the Peterson reaction (Org. React., 38, 1-223
(1990)), formation of triple bond followed by partial reduction (I. Am. Chem. Soc,
77, 3378 (1955); I. Am. Chem. Soc, 99, 2805 (1977); Synthesis, 1973, 457;
Tetrahedron 30, 3817 (1974)), etc.

(wherein R9a means R9 other than H and X1 means a leaving group such as a halogen,
rnethanesulfonyloxy, p-toluenesulfonyloxy, etc.; hereinafter the same.)
This process is alkylation. Specifically, the alkylation is carried out as in the
processes described above, e.g., in a solvent inert to the reaction, using an amine (Id)
and a compound (VIII) having a leaving group corresponding to the reaction in a
chemically equivalent amount or in an excess of either reactant, under the conditions
of cooling to heating. In some occasions, the reaction is carried out smoothly in the
presence of a base (e.g., an inorganic base such as potassium carbonate, sodium
carbonate, cesium carbonate, etc.; an organic base such as triethylamine,
diisopropylethylamine, etc.; a metal alkoxides such as potassium tert-butoxide,
sodium tert-butoxide, etc.; sodium hydride; lithium hydride; etc.), an additive
(tetra-n-butylammonium iodide, potassium iodide, sodium iodide, etc.), which is
advantageous.
A reaction solvent, which can be used, includes a solvent inert to this
reaction, such as tetrahydrofuran, dichloromethane, dichloroethane, acetonitrile,

(wherein R9b-CO- represents an optionally substituted an acyl; and X2 represents OH;
a leaving group such as a halogen, 1-hydroxybenzotriazol-l-yloxy, methoxy,
phenoxy, azido, etc., or a leaving site in a mixed anhydride or a symmetric
anhydride; hereinafter the same.)
This process is amidation. Specifically, the amidation is carried out as in the
processes described above, e.g., by reacting an amine (Id) with a carboxylic acid or
its reactive derivative (IX) in a chemically equivalent amount in accordance with the
processes described in, e.g., M. Bodanszky, "Peptide Chemistry" (1988, pages 55-73),
Nobuo Izumiya, et. al, "Basis and Experimentals of Peptide Synthesis" (1985, pages
89-142), etc.
Specifically, this reaction is preferably carried out by the method using a
condensing agent conventionally used (dicyclohexylcarbodiimide,
l-ethyl-3-(3-dimethylaminopropyl)carbodiimide, 1,l'-carbonyldiimidazole (CDI),
etc.); the mixed anhydride method using ethyl chloroformate or isobutyl
chloroformate; the symmetric anhydride method using ethoxyacetylene, an
alkynylamine such as tert-butylethynyldimethylamine, etc. If desired, a catalyst such
as 1-hydroxybenzotriazole, etc. may be used. The reaction may also be carried out by
reacting a carboxylic acid with a halogenating agent such as thionyl chloride, oxalyl
chloride, phosphorus oxychloride, etc. to convert the acid into a reactive derivative
such as an acid halide and then reacting the reactive derivative with a primary or
secondary amine. The reaction is carried out in a solvent inert to this reaction such as
tetrahydrofuran, dioxane, dichloromethane, dichloroethane, dimethylformamide,
dimethylsulfoxide, toluene, etc., if necessary, in the presence of a base (e.g., an
organic base such as triethylamine, diisopropylethylamine, pyridine, etc.; an
inorganic base such as potassium carbonate, sodium hydrogencarbonate, etc.), under
the conditions of ice cooling to heating with stirring.

(wherein R9Crepresents a group having a carbon number less than by one from the
optionally substituted lower alkyl shown by R9, hereinafter the same).
This process is reductive amination.
Specifically, the reaction is carried out as in the processes described above,
e.g., by reacting an amine (Id) with an aldehyde or ketone (X) in a conventional
manner of reductive amination, e.g., the process described in "Experimental
Chemistry Series (Maruzen)" (4th edition, 20, 1992, page 300), edited by The
Chemical Society of Iapan, etc.
Specifically, Compound (Ig) can be produced by reacting the amine with its
chemically equivalent amount of the aldehyde or ketone in a solvent inert to this
reaction such as tetrahydrofuran, dioxane, dichloromethane, dichloroethane,
dimethylformamide, dimethylsulfoxide, toluene, etc., in the presence of a reducing
agent such as sodium cyanoborohydride, sodium triacetoxyborohydride, sodium
borohydride, formic acid, etc., under the conditions of ice cooling to heating with
stirring. In some occasions, the reaction is carried out smoothly in the presence of an
acid (e.g., a Lewis acid such as titanium tetraisopropoxide, etc.; acetic acid;
p-toluenesulfonic acid, etc.), which is advantageous. The reduction described above
may also be performed in the above-described solvent inert to the reaction by
catalytic reduction in the presence of a metal catalyst such as palladium (Pd),
platinum (Pt), etc.
The reducing agent may be added immediately after mixing the primary or
secondary amine with the aldehyde or ketone or after passage of some time.
The foregoing shows the processes for producing representative compounds.
In addition, compounds other than the compounds of the present invention or raw
compounds but having similar substituents can be subIected to reactions for
modifying substituents according to the processes described above to produce the
compounds of the present invention. In addition to the processes described above,

these compounds can be produced by other well known processes, including
conventional imidation or amidination, or by the processes described in
"Experimental Chemistry Series (Maruzen)" (4th edition, 25, pages 396-427) edited
by The Chemical Society of Iapan,
Protective group Organic Synthesis, Second Ed., Iohn Wiley & Sons, Inc., or
Angew. Chem. Int. Ed. Engl. 1998, 37, p2046-2067, etc.
Compound (I) of the present invention thus produced is isolated in its free
form or as its salt. The salt of Compound (I) of the present invention can be prepared
by applying a conventional salt-making technique to Compound (I) of the present
invention as the free base.
Also, Compound (I) of the present invention or its salt may be isolated and
purified in the form of a hydrate, solvate or polymorphism thereof. The isolation and
purification are performed by applying conventional chemical operations including
extraction, concentration, distillation, crystallization, filtration, recrystallization,
various chromatography techniques, etc.
Various isomers can be separated by choosing an appropriate raw compound,
or by utilizing a difference between isomers in physical or chemical properties. For
example, the optical isomers can be converted into stereochemically pure isomers, by
choosing appropriate raw compounds or by racemic resolution of racemic
compounds (for example, by a process of optical resolution which comprises
converting the racemic compounds into diastereomer salts with ordinary optically
active acids, etc.).
[Formulation]
Various formulations conventionally used are applicable to Compound (I) of
the present invention. Representative formulations are explained below.
A pharmaceutical composition may contain one or two or more types of the
Compound (I) of the present invention or pharmaceutically acceptable salts thereof
as the effective ingredient and pharmaceutically acceptable carriers, which can be
prepared into tablets, powders, fine granules, granules, capsules, pills, liquids,
inIections, suppositories, ointments, paps or the like, using carriers and excipients
conventionally used to make pharmaceutical preparations, and other additives. The
resulting formulations are administered orally (including sublingual administration)
or parenterally.
The clinical dose of Compound (I) of the present invention or
pharmaceutically acceptable salts to human is appropriately determined, depending

on the symptom, age, sex and body weight of an individual patient, to whom
Compound (I) or pharmaceutically acceptable salts is applied. Generally, Compound
(I) or pharmaceutically acceptable salts is orally administered to an adult at a dose of
1 mg to 1000 mg per day in one portion or divided portions in the form of a solid
composition or a liquid composition. Alternatively, the compound is intravenously
administered to an adult at a dose of 1 mg to 500 mg per day in one portion or
divided portions, or intravenously administered in a sustained release manner for a
period of 1 hour to 24 hours per day. As described above, since the dose may vary
depending upon various conditions and thus, a dose below the range given above
may be sometimes sufficient.
As the solid composition for oral administration in accordance with the
present invention, tablets, powders, granules and the like are used. For such solid
composition, one or more active substances are mixed with at least one inactive
diluent, for example lactose, mannitol, glucose, hydroxypropylcellulose,
microcrystalline cellulose, starch, polyvinylpyrrolidone, or metasilicate aluminate
magnesium. Following a conventional manner, the composition may further contain
additives other than inactive diluents, for example, lubricants such as magnesium
stearate, disintegrators such as cellulose calcium glycolate, stabilizers such as lactose,
solubilization or dissolution-auxiliary agents such as glutamic acid or aspartic acid.
The tablets or pills may be sugar-coated or coated with a gastric soluble or enteric
film, using sucrose, gelatin, hydroxypropyl cellulose and hydroxypropylmethyl
cellulose phthalate, and the like.
The liquid composition for oral administration contains pharmaceutically
acceptable emulsifiers, solubilizers, suspending agents, syrups, elixirs and the like
and also contains inactive diluents conventionally used, for example, distilled water
or ethyl alcohol. The composition may further contain auxiliary agents such as
solubilization- or dissolution-auxiliary agents, moisturizers and suspending agents,
sweeteners, flavoring agents, aromatic agents and preservatives.
The inIections for parenteral administration include aseptic, aqueous or
non-aqueous solubilizers, suspending agents and emulsifiers. Aqueous solubilizers
and suspending agents include, for example, distilled water for inIections and
physiological saline. Water-insoluble solubilizers and suspending agents include, for
example, propylene glycol, polyethylene glycol, vegetable oils such as olive oil,
alcohols such as ethanol, polysorbate 80 (trade name), etc. Such composition may
further contain additives including isotonic agents, preservatives, moisturizers,

emulsifiers, dispersants, stabilizers (for example, lactose), and solubilization- and
dissolution-auxiliary agents. These are sterilized by filtration through, e.g., a bacteria
retention filter, or by blending with sterilizers or irradiation. These may also be
prepared into aseptic solid compositions and the resulting aseptic compositions are
provided for use after dissolution in aseptic water or in an aseptic solvent for
inIections, prior to use.
Furthermore, Compound (I) of the present invention may be used in
combination with therapeutics for the diseases described above or with other drugs
useful for pain by a mechanism other than the sodium channel blockage. Drugs
useful for pain, which are usable in combination, include narcotic analgesics,
antipyretic analgesics, non-steroidal antiinflammatory drugs, etc.
Examples
Next, the present invention is described in more detail by referring to
Examples but is not deemed to be limited thereto. Raw compounds used will be
explained in Reference Examples.
The chemical structures of individual compounds obtained in Examples,
Example Nos. using the compounds and specific constructions are shown in Tables
] through 13 and the physicochemical properties of these compounds are shown in
Tables 14 through 25 below.
Production examples of the raw compounds used in Examples are
specifically described by referring to Reference Examples 1 through 33. The
chemical structures of the compounds obtained in Reference Examples 4 to 15, 17,
22 to 25, 28 to 29 and 31 to 32 are shown in Table 26 and the physicochemical
properties of the compounds of Reference Examples 1 through 33 are shown in
Table 27.
Tables 1 to 25 relating to Examples and Tables 26 and 27 relating to
Reference Examples are shown at the end of the specification.
The symbols in Tables 1 to 25 relating to Examples and Tables 26 and 27
relating to Reference Examples are used to mean the following.
Rf: Reference Example No., Ex.: Example No., Me: methyl, Et: ethyl, Pr:
propyl, iPr: isopropyl, Bu: butyl, iBu: isobutyl, tBu: tert-butyl, Ph: phenyl, Ac: acetyl,
Bn benzyl, cBu: cyclobutyl, cPen: cyclopentyl, cHex: cyclohexyl, cHep: cycloheptyl,
Mo: morpholine, ThioMo: thiomorpholine, Py: pyridine, Pyrrolid: pyrrolidine,
Piperi: piperidine, Pipera: piperazine, TM: imidazole, MeO: methoxy, EtO: ethoxy,

Me2N: dimethylamino, PhO: phenoxy, BU2N: dibutylamino, yl: yl, Salt: salt, fum:
fumarate, difumarate: difumarate, dimaleate: dimaleate, Structure: structural formula,
NMR: nuclear magnetic resonance spectrum (unless otherwise indicated, 400 MHz,
DMSO-d6, TMS internal standard, ppm), MS: mass spectrum (unless otherwise
indicated, FAB or ESIm/z), Data: physicochemical property.
Reference Example 1
1) 3.32 g of aniline was added to a solution of 4.99 g of
2-chlorobenzaldehyde in 48 ml of benzene, and the mixture was heated under reflux
for 20 hours. After the reaction mixture was concentrated under reduced pressure, the
concentrate was azeotropically distilled with toluene to give 6.16 g of yellow oil. The
yellow oil was dissolved in 120 ml of acetic acid and 5.45 g of palladium acetate was
added to the solution, followed by heating under reflux for 2 hours. After cooling,
water was added to the reaction mixture and the precipitated crystals were collected
by filtration. The crystals were dissolved in 50 ml of methylene chloride, and 75 ml
of saturated aqueous sodium chloride and 50 ml of acetone were added to the
solution. The mixture was stirred at ambient temperature for 15 hours. The
precipitated crystals were collected by filtration and washed with ethanol, benzene
and methylene chloride to give 5.50 g of green crystals. The crystals were suspended
in 250 ml of benzene and 8.08 g of triphenylphosphine was added to the suspension,
followed by stirring at ambient temperature for 50 minutes. To the reaction mixture
was added 13 ml of 1.2M methyl lithium in diethyl ether .The mixture was stirred for
2 hours and 250 ml of IN hydrochloric acid was further added thereto, followed by
stirring for 2 hours. The reaction mixture was extracted with diethyl ether. The
organic layer was washed with saturated aqueous sodium chloride and then dried
over anhydrous sodium sulfate. After filtration, the filtrate was concentrated and the
resulting residue was purified by silica gel column chromatography (hexane-ethyl
acetate) to give 1.51 g of 2-chloro-6-methylbenzaldehyde as pale yellow oil.
2) Under ice cooling, 185 mg of sodium borohydride was added to a
solution of 1.51 g of 2-chloro-6-methylbenzaldehyde in 15 ml of methanol, followed
by stirring for 35 minutes. The reaction mixture was concentrated under reduced
pressure and saturated aqueous ammonium chloride was added to the residue. The
mixture was extracted with diethyl ether. The organic layer was washed with
saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate.
After filtration, the filtrate was concentrated and the resulting residue was purified by

126 ml of triethylamine and 36.0 g of molecular sieves (4A), and the mixture was
heated under reflux for 47 hours. The reaction mixture was filtered and the filtrate
was concentrated under reduced pressure. The residue was purified by silica gel
column chromatography (hexane) to give 5.23 g of colorless oil. Grignard reagent
was prepared from the oil, 0.51 g of magnesium and 25 ml of tetrahydrofuran. Under
ice cooling, a solution of 1.27 g of dimethylformamide in 15 ml of tetrahydrofuran
was added dropwise to the reagent. After stirring at ambient temperature for 45
minutes., the reaction mixture was poured into saturated aqueous ammonium chloride,
followed by extraction with diethyl ether. The organic layer was washed with
saturated aqueous sodium chloride and then dried over anyhydrous sodium sulfate
and the solvent was evaporated under reduced pressure. The resulting residue was
purified by silica gel column chromatography (hexane-ethyl acetate) to give 3.79 g of
pale yellow oil. This oil was dissolved in 40 ml of methanol. Under ice cooling, 0.32
g of sodium borohydride was added to the solution, followed by stirring at ambient
temperature for 45 minutes. The reaction mixture was concentrated under reduced
pressure and saturated aqueous ammonium chloride solution was added to the
residue, followed by extraction with ethyl acetate. The organic layer was washed
with saturated aqueous sodium chloride and then dried over anhydrous sodium
sulfate. The solvent was evaporated under reduced pressure to give 3.78 g of
(2,6-dimethyl-4-phenoxyphenyl)methanol.
The compound of Reference Example 4 was obtained in a manner similar to
Reference Example 3.
The compounds of Reference Example 5 to 15 were obtained in a manner
similar to Reference Example 1.
Reference Example 16
After 4.34 g of N-bromosuccinimide and 0.54 g of benzoyl peroxide were
added to a solution of 3.03 g of 2,3-dimethylanisole in 70 ml of carbon tetrachloride,
the mixture was heated under reflux for 30 minutes. After cooling, insoluble solid in
the reaction mixture were filtered off and the filtrate was concentrated under reduced
pressure to give an oil. The obtained oil was dissolved in 50 ml of benzene, and 5.82
g of triphenylphosphine was added to the solution. The mixture was heated under
reflux for 11 hours. After cooling, the precipitated crystals were collected by

filtration and recrystallized from methylene chloride-benzene to give 6.51 g of
(2-methoxy-6-methylbenzyl)(triphenyl)phosphonium bromide as colorless crystals.
The compound of Reference Example 17 was obtained in a manner similar
to Reference Example 16.
Reference Example 18
After 10.4 g of potassium carbonate and 6.80 ml of methyl iodide were
added to a solution of 10.0 g of 4-bromo-3,5-dimethylphenol in 100 ml of acetone,
the mixture was heated under reflux for 15 hours. The reaction mixture was
concentrated under reduced pressure and saturated aqueous ammonium chloride was
added to the residue, followed by extraction with ethyl acetate. The organic layer was
washed with saturated aqueous sodium chloride and then dried over anhydrous
sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue
was purified by silica gel column chromatography (hexane-ethyl acetate) to give 9.18
g of 4-bromo-3,5-dimethylanisole as colorless oil.
Reference Example 19
Ethyl 4-(hydroxyimino)cyclohexanecarboxylate was reacted in the presence
of cone, sulfuric acid in ethanol to produce ethyl 7-oxoazepane-4-carboxylate.
Reference Example 20
Ethyl 7-oxoazepane-4-carboxylate was reacted in the presence of lithium
aluminum hydride to produce azepan-4-ylmethanol.
Reference Example 21
8.60 ml of di-tert-butyl dicarbonate was added to a solution of 5.00 g of
2-piperidin-4-ylethanol in 50 ml of tetrahydrofuran, followed by stirring at ambient
temperature for 30 minutes. The reaction mixture was concentrated under reduced
pressure and the resulting residue was purified by silica gel column chromatography
(hexane-ethyl acetate) to give 8.80 g of an oil. The oil was dissolved in 60 ml of
dimethylsulfoxide, and the resulting solution was added 20.5 ml of triethylamine and
12.2 g of sulfur trioxide-pyridine complex, followed by stirring at ambient
temperature for 30 minutes. The reaction mixture was poured into saturated aqueous
sodium bicarbonate, followed by extraction with ethyl acetate. The organic layer was

washed with saturated aqueous sodium chloride and then dried over anhydrous
sodium sulfate. After filtration, the filtrate was concentrated and the residue was
purified by silica gel column chromatography (hexane-ethyl acetate) to give 6.40 g of
tert-butyl 4-(2-oxoethyl)piperidine-1 -carboxylate.
The compounds of Reference Examples 22 to 25 were produced in a manner
similar to Reference Example 21.
Reference Example 26
(1 -Benzylpyrolidin-3-yl)methanol was reacted in the presence of
triethylamine and sulfur trioxide-pyridine complex in dimethylsulfoxide to produce
1 benzylpyrrolidine-3-carbaldehyde.
Reference Example 27
tert-Butyl 3-oxo-8-azabicyclo[3.2.1]octane-8-carboxylate was reacted in the
presence of p-toluenesulfonylmethylisocyanide, potassium tert-butoxide and ethanol
in 1,2-dimethoxyethane to produce tert-butyl
3-cyano-8-azabicyclo[3.2.1]bctane-8-carboxylate.
The compounds of Reference Examples 28 to 29 were produced in a manner
similar to Reference Example 27.
Reference Example 30
tert-Butyl 3-cyano-8-azabicyclo[3.2.1]octane-8-carboxylate was reacted in
the presence of diisobutyl aluminum hydride in tetrahydrofuran to produce tert-butyl
3-formyl-8-azabicyclo[3.2.1]octane-8-carboxylate.
The compounds of Reference Examples 31 to 32 were produced in a manner
similar to Reference Example 30.
Reference Example 33
Under ice cooling, 18 ml of 2-(bromomethyl)-l,3-dioxolane, 9.87 g of
potassium tert-butoxide and 6.57 g of tetrabutylammonium iodide were added to a
solution of 14.0 g of methyl 2-oxopiperidine-4-carboxylate in 300 ml of
tetrahydrofuran and 50 ml of dimethylformamide, and the mixture was stirred at

70°C for 14 hours. The reaction mixture was poured into water, followed by
extraction with ethyl acetate. The organic layer was washed with saturated aqueous
sodium chloride and then dried over anhydrous sodium sulfate. After filtration, the
filtrate was concentrated and the resulting residue was purified by silica gel column
chromatography (hexane-ethyl acetate) to give 4.50 g of yellow oil. This oil was
dissolved in 90 ml of tetrahydrofuran and 1.00 g of lithium borohydride was added to
the solution under ice cooling, followed by stirring at ambient temperature for 4
hours. After saturated aqueous ammonium chloride solution was added to the
reaction mixture, the mixture was extracted with chloroform. The organic layer was
washed with saturated aqueous sodium chloride and then dried over anhydrous
sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue
was purified by silica gel column chromatography (chloroform-methanol) to give
2.60 g of colorless oil. This oil was dissolved in 30 ml of dimethylsulfoxide, and 5.14
g of triethylamine and 4.04 g of sulfur trioxide-pyridine complex were added to the
solution, followed by stirring at ambient temperature for 1.5 hour. The reaction
mixture was poured into water, followed by extraction with chloroform. The organic
layer was washed with saturated aqueous sodium chloride and then dried over
anhydrous sodium sulfate. The solvent was evaporated under reduced pressure to
give 2.36 g of l-(l,3-dioxolan-2-ylmethyl)-2-oxopiperidine-4-carbaldehyde.
Example 1
264 mg of sodium hydride (55%) was added to a solution of 2.65 g of
(2-chloro-6-methylbenzyl)(triphenyl)phosphonium chloride in 20 ml of
dimethylsulfoxide, followed by stirring at ambient temperature for 1 hour. After 994
mg of tert-butyl 4-formylpiperidine-l-carboxylate was added to the reaction mixture,
the mixture was stirred at ambient temperature for 1 hour. The reaction mixture was
poured into saturated aqueous ammonium chloride, followed by extraction with ethyl
acetate. The organic layer was washed with water and saturated aqueous sodium
chloride and then dried over anhydrous sodium sulfate. After filtration, the filtrate
was concentrated and the resulting residue was purified by silica gel column
chromatography (hexane-ethyl acetate) to give 645 mg of tert-butyl
4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine-l-carboxylate as an oil.
Example 2
As starting materials, 5.00 g of

(2,6-dimethylbenzyl)(triphenyl)phosphonium chloride and 1.79 g of tert-butyl
4-formylpiperidine-l-carboxylate were used and treated in the same manner as in
Example 1. The reaction mixture was then purified by silica gel column
chromatography (hexane-ethyl acetate) to give 192 mg of tert-butyl
4-[(Z)-2-(2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate (Example 2-1) and 1.96
g of tert-butyl 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate
(Example 2-2).
The compounds of Examples 3 to 14, 16 to 24, 27 and 28 were produced in
a manner similar to Example 1.
The compounds of Examples 15-1, 15-2, 25-1, 25-2, 26-1 and 26-2 were
produced in a manner similar to Example 2.
Example 29
Under argon atmosphere, 1M tetrahydrofuran solution of 1.3 ml of lithium
bis(trimethylsilyl)amide was added at -78°C to a solution of 300 mg of tert-butyl
4-acetylpiperidine-l-carboxylate in 4.0 ml of tetrahydrofuran, followed by stirring
for 15 minutes. To the reaction mixture, a solution of 167 mg of
2,6-dimethylbenzaldehyde in 1.0 ml of tetrahydrofuran was added, followed by
stirring at ambient temperature for 12 hours. Saturated aqueous ammonium chloride
solution was added to the reaction mixture, followed by extraction with diethyl ether.
The organic layer was washed with water and then dried over anhydrous sodium
sulfate. After filtration, the filtrate was concentrated and the residue was purified by
silica gel column chromatography (hexane-ethyl acetate) to give 235 mg of tert-butyl
4-[(E)- 3 -(2,6-dimethylphenyl)prop-2-enoyl]piperi dine-1 -carboxylate.
Example 30
Under cooling at -78°C, a solution of 1.50 g of 4-bromo-2,6-dimethylanisole
in 20 ml of tetrahydrofuran was added to a solution of 1.6M hexane solution of 4.8
ml of n-butyl lithium in 20 ml of tetrahydrofuran. The mixture was stirred for 1 hour.
A solution of 1.50 g of tert-butyl 4-(2-oxoethyl)piperidine-l-carboxylate in 20 ml of
tetrahydrofuran was added to the mixture. After stirring for 30 minutes, the mixture
was stirred at ambient temperature for further 3 hours. The reaction mixture was
poured into water, followed by extraction with ethyl acetate. The organic layer was

washed with saturated aqueous sodium chloride and then dried over anhydrous
sodium sulfate. After filtration, the filtrate was concentrated and the resulting residue
was purified by silica gel column chromatography (hexane-ethyl acetate) to give 628
mg of tert-butyl
4-[2-hydroxy-2-(4-methoxy-2,6-dimethylphenyl)ethyl]piperidine-l-carboxylate as an
oil. To the oil was added 15 ml of 10% hydrochloric acid and the mixture was heated
under reflux for 2 hours. After cooling, the reaction mixture was alkalized with 20%
aqueous sodium hydroxide solution,, followed by extraction with ethyl acetate. The
organic layer was washed with saturated aqueous sodium chloride and then dried
over anhydrous magnesium sulfate. The solvent was evaporated under reduced
pressure to give 291 mg of tert-butyl
4-[(E)-2-(4-methoxy-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate.
Example 31
Under argon atmosphere, 3 ml of propionitrile was added to a mixture of
339 mg of tert-butyl
4-[(E)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate, 89 mg of
sodium cyanide, 53 mg of tetrakistriphenylphosphine palladium and 17 mg of copper
iodide., followed by heating under reflux for 7 hours. Water was added to the reaction
mixture, followed by extraction with ethyl acetate. The extract was dried over
anhydrous magnesium sulfate and the residue was purified by silica gel column
chromatography (hexane-ethyl acetate) to give 299 mg of tert-butyl
4-[(E)-2-(4-cyano-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate.
Example 32
Under carbon monoxide atmosphere, 120 u.1 of butanol and 265 u,l of
tributylamine were added to a mixture of 409 mg of tert-butyl
4-[0i)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate and 39 mg of
dichlorobistriphenylphosphine palladium. The mixture was heated at 100°C
overnight with stirring. Then 87 mg of dichlorobistriphenylphosphine palladium, 120
u.1 of butanol and 265 μ1 of tributylamine were added to the reaction mixture and the
mixture was heated at 120°C overnight with stirring. Water was added to the reaction
mixture, followed by extraction with ethyl acetate. The organic layer was washed
sequentially with 0.1N hydrochloric acid, saturated aqueous sodium hydrogen
carbonate solution, water and saturated aqueous sodium chloride. After drying over

anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure.
The residue was purified by silica gel column chromatography (hexane-ethyl acetate)
to give 217 mg of tert-butyl
4-{(E)-2-[4-(butoxycarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate
(Example 32-1) and 123 mg of tert-butyl 4-((E)-2-{4-[(dibutylamino)carbonyl]-
2,6-dimethylphenyl}vinyl)piperidine-l-carboxylate (Example 32-2).
Example 33
Under argon atmosphere, 10 ml of toluene and 87 μl of morpholine were
added to a mixture of 300 mg of tert-butyl
4-[(E)-2-(4-bromo-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate, 110 mg of
sodium tert-butoxide, 45 mg of bisdibenzylideneacetone palladium and 48 mg of
BINAP. The resulting mixture was heated at 100°C for 11 hours with stirring. The
solvent was evaporated under reduced pressure and the residue was purified by silica
gel column chromatography (hexane-ethyl acetate) to give 289 mg of tert-butyl
4-[(E)-2-(2,6-dimethylphenyl-4-morpholin-4-yl-phenyl)vinyl]piperidine-l-
carboxylate.
The compound of Example 34 was produced in a manner similar to
Example 33.
Example 3 5
To a suspension of 133 mg of tert-butyl
4-[(E)-2-(4-cyano-2,6-dimethylphenyl)vinyl]piperidine-l-carboxylate in 5 ml of
acetone and 2 ml of water, 146 mg of hydrogen peroxide-urea complex and 7 mg of
potassium carbonate were added, followed by stirring overnight. Then, 221 mg of
hydrogen peroxide-urea complex was added and the mixture was stirred overnight,
and 293 mg of hydrogen peroxide-urea complex was further added, followed by
stirring for 4 days. An aqueous solution of sodium sulfate was added to the reaction
mixture and extracted with chloroform. The organic layer was washed with saturated
aqueous sodium chloride and then dried over anhydrous magnesium sulfate. The
solvent was evaporated under reduced pressure and the residue was purified by silica
gel column chromatography (chloroform-methanol) to give 134 mg of tert-butyl
4-{(E)-2-[4-(aminocarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate.
Example 36

To a solution of 209 mg of tert-butyl
4-{(E)-2-[4-(butoxycarbonyl)-2,6-dimethylphenyl]vinyl}piperidine-l-carboxylate in
5 ml of ethanol, 1.5 ml of IN aqueous sodium hydroxide solution was added,
followed by stirring at ambient temperature for 3.5 hours. After 1 ml of
tetrahydrofuran was added to the reaction mixture, the mixture was stirred at 50°C
overnight. The solvent was evaporated under reduced pressure, water and 1.6 ml of
IN hydrochloric acid were added thereto. The formed precipitates were collected by
filtration and dried to give 179 mg of
4-{(E)-2-[l-(tert-butoxycarbonyl)piperidin-4-yl]vinyl}-3,5-dimethylbenzoicacid.
Example 37
To a solution of 645 mg of tert-butyl
4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine-l-carboxylate in 4 ml of ethanol,
3 ml of 35% hydrogen chloride-ethanol was added, followed by stirring at ambient
temperature for 5 hours. The reaction mixture was evaporated under reduced pressure
and the residue was azeotropically distilled with 5 ml of toluene 3 times to give
crystals. The collected crystals were recrystallized from ethanol-ethyl acetate to give
377 mg of 4-[(E)-2-(2-chloro-6-methylphenyl)vinyl]piperidine hydrochloride.
The compounds of Examples 38 to 67 were produced in a manner similar to
Example 37.
Example 68
To a solution of 125 mg of
l-benzyl-4-[(E)-2-(2,6-dimethylphenyl)vinyl]-3-methylpiperidine in 3 ml of
1,2-dichloroethane, 139 mg of 1-chloroethyl chlorofofmate was added at ambient
temperature. The mixture was heated under reflux for 1 hour. After cooling, 10 ml of
methanol was added to the reaction mixture and the resulting mixture was heated
under reflux for further 30 minutes. After cooling, the solvent was evaporated under
reduced pressure. The residue was dissolved in 5 ml of ethyl acetate and the solution
was filtered. To the filtrate was added 1 ml of 4N hydrochloric acid-ethyl acetate and
the solvent was evaporated under reduced pressure. The residue was triturated in
ethyl acetate. After filtration, the obtained solid was recrystallized from ethyl
acetate-methanol to give 47 mg of
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-3-methylpiperidine hydrochloride.

The compound of Example 69 was produced in a manner similar to
Example 68.
Example 70
To a solution of 520 mg of 2-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine
rnonohydrochloride in 7 ml of dimethylformamide, 0.13 ml of methyl iodide, 0.58 ml
of triethylarnine and 572 mg of potassium carbonate were added, followed by stirring
at ambient temperature for 12 hours. The reaction mixture was poured into water,
followed by extraction with ethyl acetate. The organic layer was washed with
saturated aqueous sodium chloride and then dried over anhydrous sodium sulfate.
After filtration, the filtrate was concentrated and the resulting residue was purified by
silica gel column chromatography (chloroform-methanol) to give 470 mg of
2 -[(E)-2-(2,6-dimethylphenyl)vinyl]-l-methylpiperidine. The product was dissolved
in 5 ml of ethanol, and 2.5 ml of 35% hydrogen chloride-ethanol was added to the
solution, followed by stirring at ambient temperature for 1 hour. The reaction mixture
was evaporated under reduced pressure and the residue was azeotropically distilled
with 5 ml of toluene 3 times to give crystals. The collected crystals were
recrystallized from ethanol-ethyl acetate to give 395 mg of
2-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-methylpiperidine rnonohydrochloride.
The compounds of Examples 71 to 77 were produced in a manner similar to
Example 70.
Example 78
Under ice cooling, 6.77 ml of triethylarnine and 3.87 ml of chloroacetyl
chloride were added to a solution of 9.96 g of
4-[(E)-2-(2.6-dimethylphenyl)vinyl]piperidine in 150 ml of tetrahydrofuran. After
stirring at ambient temperature for 20 minutes, 200 ml of water was added to the
mixture. After the organic layer was fractionated, the aqueous layer was extracted
with diethyl ether. The combined organic layer was and washed with saturated
aqueous sodium chloride. After drying over anhydrous magnesium sulfate, the
solvent was evaporated under reduced pressure. The residue was purified by silica
gel column chromatography (hexane-ethyl acetate). The collected crystals were
washed with diisopropyl ether-hexane and dried under reduced pressure to give 10.69
gof l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine.

The compounds of Examples 79 to 84 were produced in a manner similar to
Example 78.
Example 8.5
To a solution of 200 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine
monohydrochloride in 5 ml of dimethylformamide, 111 μl oftriethylamine, 107 mg
of imidazole-4-carboxylic acid, 161 mg of 1-hydroxybenzotriazole and 228 mg of
1 -ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride were added at
ambient temperature. After stirring at ambient temperature overnight, the reaction
mixture was concentrated under reduced pressure. After 50 ml of chloroform and 15
ml of saturated aqueous sodium hydrogen carbonate solution were added to the
reaction mixture, the organic layer was fractionated and the solvent was evaporated
under reduced pressure. The residue was purified by silica gel column
chromatography (chloroforrn-methanol-ammonia water) to give 280 mg of colorless
oil. The oil obtained was dissolved in 2 ml of ethanol, and 226 \x\ of 4N hydrochloric
acid-ethyl acetate was added to the solution. The precipitated crystals were collected
by filtration and washed with diethyl ether. The crystals were recrystallized from
ethanol-diethyl ether to give 191 mg of
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-(lH-imidazol-4-ylcarbonyl)piperidine
monohydrochloride.
The compounds of Examples 86 to 107 were produced in a manner similar
to Example 85.
Example 108
To a solution of 250 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine
monohydrochloride in 5 ml of dimethylformamide, 138 |_tl oftriethylamine, 222 mg
of 2-[(tert-butoxycarbonyl)amino]-2-methylpropionic acid, 201 mg of
I-hydroxybenzotriazole and 286 mg of
l-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride were added at
ambient temperature. After stirring at ambient temperature overnight, the reaction
mixture was concentrated under reduced pressure. After 50 ml of chloroform and 15
ml of saturated aqueous sodium hydrogencarbonate solution were added to the
residue, the organic layer was fractionated and the solvent was evaporated under
reduced pressure. The residue was purified by silica gel column chromatography

(hexane-ethyl acetate) to give 364 mg of white crystals. The collected crystals were
dissolved in 5 ml of 4N hydrochloric acid-ethyl acetate. After stirring at ambient
temperature for 1 hour, 10 ml of diethyl ether was added to the solution, followed by
stirring for 30 minutes. The precipitated crystals were collected by filtration and
washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether
to give 227 mg of (2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-l,l-
dimethyl-2-oxoethyl)amine monohydrochloride.
The compounds of Examples 109 to 122 were produced in a manner similar
to Example 108.
Example 123
To a solution of 300 mg of 4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine
monohydrochloride in 5 ml of ethanol, 736 mg of ethyl acetimidate hydrochloride
and 996 μ1 of triethylamine were added at ambient temperature. After stirring at
ambient temperature overnight, the reaction mixture was concentrated under reduced
pressure After 50 ml of chloroform and 15 ml of saturated aqueous sodium
hydrogencarbonate solution were added to the reaction mixture, the organic layer
was fractionated and the solvent was evaporated under reduced pressure. The residue
was purified by silica gel column chromatography (chloroform-methanol-ammonia
water) to give 313 mg of pale yellow crystals. The collected crystals were dissolved
in 5 ml of ethanol, and 305 μ1 of 4N hydrochloric acid-ethyl acetate was added to the
solution. The solvent was evaporated under reduced pressure. The residue was
crystallized from ethanol-diethyl ether and the precipitated crystals were collected by
filtration and washed with diethyl ether. The crystals were recrystallized from
ethanol-diethyl ether to give 89 mg of
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(1 -iminoethyl)piperidine monohydrochloride.
Example 124
349 mg of lH-pyrazole-1-carboxamidine and 1.45 ml of
N,N-diiso propylethylamine were added to a solution of 300 mg of
4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine monohydrochloride in 5 ml of
dimethylformamide at ambient temperature. After stirring at ambient temperature
overnight, the reaction mixture was concentrated under reduced pressure. The residue
was purified by silica gel column chromatography (ethyl acetate-ethanol-water) to

give 427 mg of white crystals. The obtained crystals were dissolved in 5 ml of
methanol, and 415 u,l of 4N hydrochloric acid-ethyl acetate was added to the solution.
The solvent was evaporated under reduced pressure and the residue was crystallized
from ethanol-diethyl ether. The precipitated crystals were collected by filtration and
washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl ether
to give 154 mg of l-amidino-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine
monohydrochloride.
Example 125
84 mg of IH-imidazole and 142 mg of potassium carbonate were added to a
solution of 300 mg of
l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidinein 5 ml of
acetonitrile, followed by heating under reflux for 3 hours. After cooling, saturated
aqueous sodium hydrogencarbonate solution was added to the reaction mixture,
followed by extraction with chloroform. The organic layer was concentrated under
reduced pressure and the residue was purified by silica gel column chromatography
(chloroform-methanol-ammonia water) to give 314 mg of
4-[(E)-2-(2,6-dimethylphenyl)vinyl]-l-(lH-imidazol-l-ylacetyl)piperidine as yellow
crystals. A portion of 288 mg from the crystals was dissolved in 2 ml of ethanol and
334 μ1 of 4N hydrochloric acid-ethyl acetate was added to the solution, followed by
concentrating under reduced pressure. The residue was crystallized from
ethanol-diethyl ether and the crystals were collected by filtration. The crystals were
then washed with diethyl ether. The crystals were recrystallized from ethanol-diethyl
ether to give 188 mg of
4- [(E)-2-(2,6-dimethylphenyl) vinyl] -1 -(1 H-imid azol-1 -ylacetyl)piperi dine
monohydrochloride.
The compounds of Examples 126 to 196 were produced in a manner similar
to Example 125.
Example 197
329 mg of tert-butyl (3S)-piperidin-3-ylcarbamate and 189 mg of potassium
carbonate were added to a solution of 400 mg of
l-(chloroacetyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine in 10 ml of
acetonitrile, followed by heating u+nder reflux for 2 hours. After the reaction mixture

was concentrated under reduced pressure, chloroform and saturated aqueous sodium
hydrogencarbonate solution were added to the residue, then the organic layer was
fractionated. The solvent was evaporated under reduced pressure. The residue was
purified by silica gel column chromatography (chloroform-methanol-ammonia
water). The obtained oil was dissolved in 10 ml of ethanol, and 10 ml of 4N
hydrochloric acid-ethyl acetate was added to the solution, followed by stirring at
ambient temperature for 3 hours. The reaction mixture was concentrated under
reduced pressure and the resulting residue was crystallized from
2-propanol-diisopropyl ether. The crystals were recrystallized from water-ethanol to
give 473 mg of (3S)-l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-
oxoethyl)p:iperidine-3-amine dihydrochloride.
The compounds of Examples 198 to 206 were produced in a manner similar
to Example 197.
Example 207
454 ul of 37% aqueous formaldehyde solution and 175 ul of acetic acid
were added to a solution of 219 mg of
(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)tetrahydro-2H-
pyran-4-ylamine in 5 ml of dichloroethane, followed by stirring at ambient
Temperature for 2 hours. Subsequently, 388 mg of sodium triacetoxyborohydride was
added to the reaction mixture, followed by stirring at ambient temperature for 1 hour.
Saturated aqueous sodium hydrogencarbonate solution and chloroform were added to
the mixture, then the organic layer was fractionated and the solvent was evaporated
under reduced pressure. The residue was purified by silica gel column
chromatography (chloroform-methanol-ammonia water). The resulting oil was
dissolved in 5 ml of ethanol, and 172 u.1 of 4N hydrochloric acid-ethyl acetate was
added to the mixture. The solvent was evaporated under reduced pressure. The
residue was crystallized from 2-propanol-diisopropyl ether. The crystals were
recrystallized from 2-propanol-diisopropyl ether to give 201 mg of (2-{4-[(E)-
2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)methyl(tetrahydro-2H-
pyran-4-yl)aminemonohydrochloride.
The compounds of Examples 208 to 222 were produced in a manner similar
to Example 207.

Example 223
A solution of 200 mg of
4-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl}-2-oxoethyl)morpholine in
1 ml of tetrahydrofuran was added dropwise to a suspension of 42 mg of lithium
aluminum hydride in 6 ml of tetrahydrofuran under ice cooling, followed by heating
under reflux for 2 hours. The mixture was then allowed to cool. Under ice cooling,
42 μ1 of water, 42 μl of 15% aqueous sodium hydroxide solution and then 126 ul of
water were sequentially added to the reaction mixture. After stirring at ambient
temperature for 30 minutes, 500 mg of anhydrous sodium sulfate was added and
insoluble solid was filtered. The filtrate was evaporated under reduced pressure and
the residue was purified by silica gel column chromatography
(chloroforrn-methanol-ammonia water) to give 150 mg of yellow oil. Aportion of
143 mg from the oil was dissolved in 5 ml of ethyl acetate, and 2 ml of 4N
hydrochloric acid-ethyl acetate was added to the solution. The solvent was
evaporated under reduced pressure and the residue was washed with acetonitrile to
give 133 mg of
4-(2- {4-[|E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1 -yl} ethy l)morpholine
dihydrochloride.
The compound of Example 224 was produced in a manner similar to
Example 223.
Example 225
675 μl of morpholine was added dropwise to a solution of 380 mg of
l-(acryloyl)-4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidine in 10 ml of toluene. The
mixture was heated under reflux for 2 days in total. After the reaction mixture was
concentrated under reduced pressure, the residue was purified by silica gel column
chromatography (chloroforrn-methanol-ammonia water). The obtained oil was
dissolved in 5 ml of ethanol, and 2 ml of 4N hydrochloric acid-ethyl acetate was
added to the solution. The solvent was evaporated under reduced pressure. The
precipitated crystals were recrystallized from ethanol to give 450 mg of
4-(3-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-3-oxopropyl)morpholine
monohydrochloride.

Example 226
After 3 ml of 10% hydrochloric acid was added to a solution of 818 mg of
4 -[(E)-2-(2,6-dimethylphenyl)vinyl]-1 -(1,3-dioxolane-2-ylmethyl)piperidin-2-one in
10 ml of tetrahydrofuran, the mixture was heated under reflux for 4.5 hours. After
cooling, the reaction mixture was poured into saturated aqueous sodium hydrogen
carbonate solution and extracted with ethyl acetate. The organic layer was washed
with water and saturated aqueous sodium chloride. After drying over anhydrous
sodium sulfate, the solvent was evaporated under reduced pressure to give 685 mg of
{4-[(E)-2-(2,6-dimethylphenyl)vinyl]-2-oxopiperidin-l-yl}acetaldehyde.
In addition to the compounds described in Examples, the compounds given
in Tables 28 to 30 can be obtained by the processes described above, the processes
described in Reference Examples and Examples, processes known to ordinary skill in
the art and their modifications, without requiring any special experiments. Tables 28
to 30 are placed at the end of the specification, following Tables 1 to 27.
INDUSTRIAL APPLICABILITY
The compounds of the present invention have the sodium channel inhibitory
action and are useful as pharmaceuticals, especially therapeutics for diseases
associated with sodium channel and symptoms accompanied by these diseases,
preferably as analgesics for neuropathic pain.
For example, neuropathic pain means a pain caused by dysfunction of the
central or peripheral nervous system and includes diabetic neuropathic pain, etc.
[Pharmacological Tests]
Hereinafter, experiments on the sodium channel inhibitory action using
representative compounds of the present invention and animal tests using mice and
rats are described in detail.
(Experiment on sodium channel inhibitory action)
The sodium channel inhibitory action of representative compounds in
Compound (I) of the present invention was confirmed by experiment of [14C]
guanidine uptake using rat brain tissues. The [14C] guanidine uptake experiment was
performed by the method of Bonisch et al.(British Iournal of Pharmacology 108,
436-442, 1993) with some modifications. The [14C] guanidine was used as a sodium

tracer, and the inhibitory activity on uptake of [ C] guanidine induced by veratridine
as a sodium channel activator into rat cerebral cortex primary neurons was measured.
a. Preparation of rat cerebral cortex primary neuron culture system
Pregnant rats (Wistar, female, 19 days of gestation) were anesthetized with
ether. The animals were bled to death by giving incision through the carotid artery.
The fetuses were taken out of the pregnant rats and after ethanol sterilization, the
cerebral cortex was removed from the fetuses. The cerebral cortex was digested with
papain and dispersed in culture medium, followed by plating on a
poly-L-lysine-coated 96-well white plate at a density of 2.5 x 105 cells/well.
Incubation was performed in a CO2 incubator (37°C, 5% CO2) for 2 days.
b. Assessment of test compounds
After each well was washed once with an assay buffer (135 mM choline CI,
5 mM KC1, 1 mM MgS04, 5.5 mM glucose, 1 mg/mL BS A, 10 mM Hepes-Tris, pH
7.4), a fresh assay buffer was added to the well, followed by incubation at 25°C for
10 minutes. Then, a reaction solution (a test compound, [14C] guanidine and 100 |I.M
veratridine) was replaced for the buffer, followed by incubation at 25°C for 15
minutes. The reaction was terminated by washing 3 times with a cold wash buffer
(135 mMNaCl, 5 mM KC1, 1 mMMgS04, 10 mM Hepes-Tris, pH 7.4). To each
well, 17 \xL of O.lNNaOH was added. After agitation, 100 uL of scintillator was
added to the well and further agitation was continued. The radioactivity was
quantified by a liquid scintillation counter. In each experiment, the sodium
channel-specific uptake of the whole uptake was designated as portion that was
inhibited by 1 mM mexiletine. The action of the test compound on sodium channel is
expressed as 50% inhibition concentration(ICso) based on the specific uptake.
As shown in Table 31, the compounds of the present invention exhibited
excellent inhibitory action.

(Analgesic action on animal with streptozotocin-induced diabetic neuropathy)
Representative compounds of Compound (I) of the present invention were
assessed for the analgesic action in mice with streptozotocin (STZ)-induced diabetic
neuropathy to confirm the effect on neuropathic pain. The assessment was performed
by the method of Kamei et al. (Pharmacology Biochemistry & Behavior 39, 541-544,
1991) with some modifications.
Male ICR mice of 4 weeks old were intraperitoneally inIected with 200
mg/kg weight of STZ to prepare mice with diabetic neuropathic pain. The analgesic
action was assessed by the tail pinch test. Specifically, the analgesic action was
detected as prolongation in withdrawal latency (in seconds), i.e., the time until the
animal showed head-turning response after the tail was pinched with forceps. On
Day 14 following the STZ inIection, a pretest was carried out to determine the
response latency before the administration of a test compound. Only the animals
showing not longer than 3 seconds of the response latency in the pretest were used
for the test compound assessment on the following day (Day 15 after STZ inIection).
In the test compound assessment, the response latency after the
administration of a test compound was measured. The test compound was orally
administered at a dose of 30 mg/kg, 45 minutes prior to the response latency
measurement
The analgesic action of a test compound is expressed as prolongation of

latency (in seconds) calculated by the formula: (response latency after administration
of a test compound) - (response latency before administration of a test compound).
As shown in Table 32, the representative compounds of the present
invention displayed the prolongation of latency (in seconds) of about 1 to 5 seconds.
Separately, a test was conducted in a similar fashion, using a solvent (10% w/w
DMSO/water) in place of the compound of the present invention. The results indicate
that the prolongation of latency (in seconds) was 0.69 ± 0.38 second (mean +
standard error).
Generally in this analgesic test, the prolongation of at least about 1 second is
considered to be effective and when the prolongation is longer than 1.5 second, the
activity is rated as excellent; when the prolongation exceeds about 2 seconds, the
analgesic action is rated as extremely excellent. Accordingly, the compounds tested
in Examples have more excellent activities as compared to those of Comparative
Examples 1 and 2. Mexiletine showed the prolongation of about 3 seconds. .

Comparative Example 1:
Compound described in Example 308 (Patent Literature 1: EPC 1254904)
Comparative Example 2:
Compound described in Example 334 (Patent Literature 1: EPC 1254904)
(Anti-allodynia effect in rats with L5/L6 spinal nerve ligation)
One of the maIor symptoms in neuropathic pain is a markedly lowered
threshold of response to tactile stimulation (allodynia). The anti-allodynia effect of
the representative compounds in the compounds of the present invention was
confirmed by assessing the analgesic action in L5/L6 spinal nerve ligation rats. The
assessment was performed by the method of Kim and Chung (Pain 50, 355-363,

1992) with some modifications.
Under pentobarbital anesthesia, male SD rats of 5 or 6 weeks old were given
surgery to ligate both the left L5 and L6 lumbar nerves tightly with silk threads. For
the assessment of analgesic action, the von Frey hair test was adopted. That is, the
animal's hindpaw was picked with hair and the lowest strength of hair for limb
withdrawal response was designated as a response threshold (log gram) to
mechanical stimulation. Since it was confirmed in prior test that the response
threshold of the animal's hindpaw ipsilateral to the side of ligation was markedly low
during days 7 to 14 after the surgery (in the state of allodynia), the anti-allodynia
effect of a test compound was assessed on any day between days 7 and 14 from the
surgery. On the day before the assessment of a test compound, the response threshold
before administration of a test compound was measured. The animals were divided
into 4 to 5 groups so that differences in the mean values of response thresholds
before administration among the groups and variation within groups become small.
In the assessment of a test compound, the response threshold after administration of
the test compound was measured. The test compound was orally given 30 minutes
before measurement of the response threshold. The anti-allodynia action potency of a
test compound is expressed as ED50. In the calculation of the ED50, the thresholds of
ipsilateral and contralateral paws in the solvent group were designated as 0% and
] 00%, respectively.
Compounds having excellent ED50 values were found in the compounds of
the present invention, whereas mexiletine showed ED50 value of about 70 mg/kg.
It was confirmed by the test described above that the representative
compounds in the compounds of the present invention show the sodium channel
inhibitory action. It was also confirmed that these compounds with oral
administration exhibited the analgesic action, that was more excellent than that of
heretofore known compounds, in the disease animal models, i.e., mice with diabetic
neuropathy and L5/L6 spinal nerve ligation rats. Based on the foregoing results, it
was confirmed that some compounds of Compound (I) of the present invention
showed sodium channel inhibitory action that was more excellent than that of
mexiletine. It was also confirmed that some compounds of Compound(I) of the
present invention with oral administration showed analgesic action that was equal or
superior to that of mexiletine in the animal disease model, i.e., mice with diabetic
neuropathy.
Based on the evidence mentioned above, it was confirmed that the

compounds of the present invention are excellent sodium channel inhibitors and are
useful for relief of pain, especially neuropathic pain such as pain accompanied by
diabetic neuropathy, etc. ,
/

1. A nitrogen-containing heterocyclic derivative represented by formula (I)
below:

(wherein symbols in formula (I) above have the following significance:
R1 and R2, which may be the same or different, represent H-, an optionally
substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower alkyl-O-CO-,
H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an
aryl-O-, an acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl^N-, an acyl-NH-, a
halogen, nitro, a heterocyclic group, or cyano;
R~' and R4, which may be the same or different, represent an optionally
substituted lower alkyl, a cycloalkyl, an acyl, HO-CO-, a lower alkyl-O-CO-,
H2N-CO-, a lower alkyl-HN-CO-, a (lower alkyl)2N-CO-, HO-, a lower alkyl-O-, an
acyl-O-, H2N-, a lower alkyl-HN-, a (lower alkyl)2N-, an acyl-NH-, a halogen, nitro,
or cyano;
R and R6, which may be the same or different, represent H-, a lower alkyl,
or a halogen;
R and R8, which may be the same or different, represent H-, a lower alkyl,
HO-, a lower alkyl-O-, or a halogen;
R and R8 may be combined together to form oxo (0=);
R!' represents H-, an optionally substituted lower alkyl, an optionally
substituted cycloalkyl, an optionally substituted acyl, a lower alkyl-C (=NH)-,
HO-CO-, an optionally substituted lower alkyl-O-CO-, H2N-CO-, an optionally
substituted lower alkyl-HN-CO-, an (optionally substituted lower alkyl)2N-CO-,
H2NC(=NH)-, H2NC(=NCN)-, H2NC(=N-CONH2)-, H2NC(=NS(=0)2NH2)-,
an optionally substituted lower alkyl-S02- or an optionally substituted heterocyclic
group-S02-;
R10, Ru, R12 and R13, which may be the same or different, represent H-, or a
lower alkyl, and two groups from R10, Rn, R12 and R13 may be combined together to

form oxo (0=);
A represents a nitrogen-containing saturated heterocyclic group; and,
n represents 0,1 or 2, provided that n is zero when A is a nitrogen-containing
saturated heterocyclic group other than piperidine group;, or a pharmaceutkaliy
acceptable salt thereof.
2.The nitrogen-containing heterocyclic derivative as claimed in claim 1, or a
pharmaceuticaily acceptable salt thereof, wherein the nitrogen-containing
saturated heterocyclic group shown by symbol A in the formula (I) is a nitrogen-
containing saturated monocyclic heterocyclic group or a nitrogen-containing
saturated bridged ring.
3. The nitrogen-containing heterocyclic derivative as claimed in claim 2, or a
pharmaceuticaily acceptable salt thereof, wherein the nitrogen-containing
saturated heterocyclic group shown by symbol A in the formula (I) is a nitrogen-
containing saturated monocyclic heterocyclic group.
4. The nitrogen-containing heterocyclic derivative as claimed in claim 3, or a
pharmaceutkaliy acceptable salt thereof, wherein the nitrogen-containing
saturated heterocyclic group shown by symbol A in the formula (I) is a 6-
membered nitrogen-containing saturated monocyclic heterocyclic group.
5. The nitrogen-containing heterocyclic derivative as claimed in any one of claims
1 through 4, or a pharmaceuticaily acceptable salt thereof, wherein symbols R7
and R8 in trie formula (I) above, which may be the same or different, represent
H , a lower alkyl, H0-, a lower alkyl-O-, or a halogen.

6. The nitrogen-containing heterocyclic derivative as claimed in any one of claims
through 5, or a pharmaceutically acceptable salt thereof, wherein symbol n in the
formula (I) is 0.
7. The nitrogen-containing heterocyclic derivative as claimed in any one of claims
1 through 6, or a pharmaceutically acceptable salt thereof, wherein symbol R9 in
the formula (I) is H.
8. The nitrogen-containing heterocyclic derivative as claimed in any one of claims
1 through 6, or a pharmaceuticaHy acceptable salt thereof, wherein symbol Rg in
the formula (I) is an optionally substituted lower alkyl.
9. The nitrogen-containing heterocyclic derivative as claimed in claim 8 or a
prarmaceutically acceptable salt thereof, wherein the substituent in the
optionally substituted tower alkyl shown by symbol R9 in the formula (I) is at
least one substituted selected from Group a below:
Group a (1) a halogen, (2) HO, (3) a lower alkyl-0-, (4) H2N; (5) a lower
alkyl-NH-, (6) a (lower alkyl)2N-, (7) an aryl and (8) a heterocyclic group.
1(|. The nitrogen-containing heterocyclic derivative as claimed in any one of
claims 1 through 6, or a pharmaceuticaHy acceptable salt thereof, wherein
symbol R9 n the formula (I) is an optionally substituted acyl.

11.The nitrogen-containing heterocyclic derivative as claimed in claim 10, or a
pharmacautically acceptable salt thereof, wherein the optionally substituted acyl
shown by symbol R9 in the formula (I) is an optionally substituted lower alkyl-
CO-, an optionally substituted cycloalkyl-CO-, an optionally substituted aryl-CO-,
an optionally substituted heterocyclic group-CO-or an optionally substituted
heterocyclic group-lower alkyl-CO-.
12. The nitrogen-containing heterocyclic derivative as claimed in claim 10 or 11,
or a pharmaceutically acceptable salt thereof, wherein the substituent in the
optionally substituted acyl shown by symbol R9 in the formula (I) is at least one
substitutent selected from the Group b below;
Group b (1) HO, (2) a tower alkyl-0-,(3) R101 and R102, which may be the
same or different, represent (i) H, (ii) a tower alkyl which may optionally be
substituted with HO, a lower alkyl-O-, NH2, H2N-CO-, an acyl-NH-, a lower alkyl-
NH-, a cycloalkyl, a HO-cycloalkyl, a heterocyclic group or a (lower alkyl)2N-,(iii)
an acyl, (iv) a lower alkyl-O-CO-, (v) a heterocyclic group, or (vi) an aryl which
may optionally be substituted with a halogen, (4) a halogen, (5) oxo (0*), (6) a
cycloalkyl which may be substituted with R101 and R102N, (7) an aryl, (8) a
heterocyclic group, (9) a tower alky I which may optionally be substituted with
HO, a tower alkyl-O-, an aryl, an acyl or a heterocyclic group, (10) an acyl which
nay optionally be substituted with oxo(0=), (11) H2N-CO-, (12) a tower alkyl-
SO2, and (13) a heterocyclic group-SOr-
13. The nitrogen containing heterocyclic derivativer as claimed in any one of
claims 1 through 6 or a pharmaceutically acceptable salt thereof, wherein symbol
R9 in the formula (1) is H0-0C-, an optionally substituted lower alkyl-0-CO-,

HN2CO-. an optionally substituted lower alkyl-NH-CO-, an (optionally
substituted lower alkyl)2 N-CO- or an optionally substituted lower alkyl-S-S02.
14.The nitro-gan containing heterocyclic derivative as claimed in claim 1, or a
pharmaceutically acceptable salt thereof, which is at least one compound
selected from the group consisting of:
4| (E)-2-{2,6 -dimethy lphenyl)vinyl]quinuclidine,
tert-buty14(2E)-3-(2,dimethylphenyl)prop-en-1-yl]piperidine-1darboxylate/
tert-butyH-[(2E)-3K2,64ime1hylphe!iyl)-l-metty
catoxylate,
tert-buutyl4-[(2E)-3-(2,dimethylrItenyl)prop-2
4 [(E)-2-(2-':hloro-6-methyiphenyl)vinyl]piperidine,
4[Z)-2-(2/6-dimethylphenyl)vinyl]piperldine/
4[(E)-2-(2,6-dimethylphenyl)vinyl]piperldine,
3 5-dimethyl-4-[(E)-2-piperidin-4-ylvinyl)b€nzonitrile,
N ,N, 3,5-teb amethyR-[(E)-2-piperkIin-4-ylvlnyl]aniHne,
2[{E)-2-(2,6-dimethylpnenyl)vinyl]piperidine,
4 [(E)-2-(2,6-dimethylphenyl)vinyl]acepane,
4[(2E)-3-(2f6dlimethylpbenyl)prop-2-en-l-yl]piperidine/
4 [(2E)-3-{2r6-dimethylphenyl)prop-2-en-yl]piperidina,
(2E)-3-(2,6-dimethylphenyl)-l-piperidin-4-ylprop-2-en-i-on8,

3-[(E)-2-(2,6-dimethylphenyl)vinyl]-1-methylpiperidinel
1-benzyl-4-[(E)-2-(2,6-dimtthylphenyl)vinyl]pipe ridintf
(2-{4-[(E) -2-(2,6dimethylphenyl)vinyl]piperidln-1 -yl}ethyl)dimethylamine,
5-({4-[(E) -2-(2,6-dimethyIphenyl)vinyl]piperidin-l -yI} carbonyl)-1H-1 ;2,4-triazol-
3-amine,
4-(2-{4-[(E)-2-(2/6-dimethy1-4phenoxyphenyl)vinyt]piptridin-l-y!}-2-
oxoethyl)morpholine,
l-(2-0-[(E)-2-(2,6dimethylphenyl)vJnyl]plperldin-HI}-2OXOethyl)-4-pyrklin-3-
ylcarbonyl)piperine,(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]pipridin-1-yl}-1,1-
dimethyl-2-oxoethyl)amine,
[l-({4-[(E)-2-(2,6dimethylphenyl)vinyl]piperidin
4-(2-{4-[2E)-3-(2,6-dimethylphenyl)prop-2-en-l-yl]piperidin-l-yl}-2-
cxorthyl)morpholine
4-[(E)-2-(2,6dimethylphenyl)vlnyl]-l-[(2S)i)yrolkJln-2-ykarbonyl]piperidin€/
4-[(E)-2H2r6dimethylphenyl)vinyl]-1-1lH-imklazol-l-ylKeryl)piperidinc,
N-(2-{4-[(E)-2-(2/6dimethylphenyl)vinyl]piperidio-l-yl}-2-oxoethyl)oxttane-3-
smine,
N-{2-[(2-[4-[(E)-2(2/6-dimtthylphenyl)vinyl]piptrid)n-l-yl]-2-
oxoethyl)amino]ethyl}acetamide,
2-[(2-{4-[(E)-2-(2/6-dimethylphenyl)vinyl]piperidin-l-yl}-2-
oxoethyl)amino]ethanol.
l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piridin-l-y}-2-oxoetyhy)Xoethyl)piperidln-2-
carboxamkide,
l-(2-{4-(E)-2-(2,6-dimethytphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-3^-
dimethylpiperidlne,

4[(E)-2-(2,6-dimethyiphenyl)vinyl]-l-[(4-pyrolidin-l-ylpiperidin-i-
y)acetyl]piperidine,
4(2-{4-[(E)-2,2,dimtmylphenyl)vinrl]plperidin-l-yl}-2-xoethy!)morpho!lne
[4(2M4-[(fi)-2-(2,dimethylphenyl)vinyl]piptrk}in-l-yl}-2-xc)ethyl)morpholine-
2-yl]methanol,
4-(2-{4-[(E)-2-(2,dimethylphenyl)vinyl]piperidln-l-yl}-2'OXoethyl)-l,4-
oxazepane,
H2M4-[(E)-2K2,dim«thylphenyl)viny1)piperidin-1-yl}-2-oxoethyl)pipe
carboxamkie,
[(2R)-4-(2 {4-[(E)-2-(2,6-dimethylphenyl)vinyi]piperidin-1-yl}-2-
oxoethyl)morpholin-2-yl]methanolo,
(2R)-l-(2-{4-[(E)-2-(2.6-dimethYlphtnYl)vinyl]piperidln-l-yU-2-
oxoethyi)piptridine -2-carboxamkfe,
(2S)-l-(2-{4-[(E)-2-{2f6-dlmtthylphtnyI)vinyl3plptrldin-l-yl}-2-
oxoethyl)piper Wine -2-carboxamfcte,
[(2S)-4-(2"{4-[(E)-2-(2,6-dimcthylphenyl)v»nyl]piper»din-l-yl}-2-
oxoethyl)morpholin-2-yl]mtttonol,
[(3R)-l-(2-{4-[(E)-2-(2,6-dimelhylphenyl)vinyl3piperldin-l-yl}-2-
oxoethyl)piperKlin-3irl)methanol,
[(3S)-1-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-1-yl}-2-
oixoethyl]piperidin-3-yl]methanol,
(2R)-2-({4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-ylKarbonyl-l-
Methylpiperidine,
4-[(E)-2(2,6-dimtthylphtnyl)yinyl]-l-Oixolylpiptrkiint,
(3S)-l-(2-{4-[(E)-2-(2,6-dimethylphenyl)vinyi]piperldin-l-yl}-2-
oxoethy!)pipefidin-3-ol,

(3R)-N-2-{4-[(E)-2-(2,6-dimethylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)-N-
methytetrahydrofuran-3-amine,
(35)-N-2-{(E)-2-(2,6-dimethylphenyl)vinyl]pip€ridin-l-yl}-2-oxoethyl)-N-
methyltttrahydrofuren-3-emint,
l-(2-0-[(E)-2K2,6-Dimethylphenyl]Ylnyl]piperkiin-l-yl}-2-oxoethyl)piperidin€-4-
amine,
1-(2-{4-[(E)-2-(2,6-Dimtthylphenyl)vinyl]piperidin-l-yl}-2-oxoethyl)pip•rzin•/
(lMR)-2(2-{4-[(E)-2-(2,6-dimethylphenyl)vlnyl]piperidin-l-yl}-2-xoethy0-2,5-
(Ii,i23bicycb [2,2,1] heptane, and
l2-{4-[(E)-2H2,6dimethylphenyl)vinyl]piperdin-1-yl}-2-ox)XMthyl)methyl[(3R)-
ie trahydrofur an-3-yI]amine.
15. A pharmaceutical composition comprising the nitrogen-containing
heterocyclic derivative as claimed in any one of claims 1 through 14, or a
pharmaceutically acceptable salt thereof.
16. A pharmaceutical composition, which is a sodium channel inhibitor
comprising a nitrogen-containing heterocyclic derivative represented by formula
(II) below:

(wherein symbols in formula (II) above have the following significance:
R1and R2, which may be me same or different, represent H-, an optionally
substituted lower alkyl, a cycloalkyl, an aryl, an acyl, HO-CO-, a lower elkyl-O-
CO ,H2N-C0-, a lower alkyl-HN-CO-, a (lower alkyl)2N-C0-,H0-, a lower alkyl-0-,
an aryl-O-, an acyl-O-, H2N-, a lower afcyl-HN-, a (tower alkyl)2N-, an acyl-NH-,a
halogen, nitro, a heterocyclic group, or cyano;
R3 and R4, which may be the same or different, represent an optionally
substituted lower alkyl, a cycioalkyl, an acyl, HO-CO-, a lower akyl-O-CO-, H2N-
C0- , a lower akyl-HN-CO-, 2 (lower alkyl)2N-CO-, HO-, a tower alkyl-O-, an
acyl-0-, H2N-, a lower alkyl-HN-, a (tower alkyl)2 N-, an acyl-NH-, a halogen,
nitro, or cyano;
R5 and R6, which may be the same or different, represent H-, a lower alkyl, or
halogen;
R7 and R8, which may be the same or different, represent H-, a tower alkyl, HO-,
a tower afcyl-O-, or a halogen;
R7 and R8 may be combined together to form oxo (0«);
R9 represents H-, an optionally substituted tower alkyl, an optionally substituted
cyctoakyl, an optionally substituted acyl, a lower alkyl-C(=NH)-, HO-CO-, an
optionally substituted tower alkyl-0-CO-, H2N-CO-, an optionally substituted
tower alkyl -HN-CO-, an (optionally substituted tower aklyl)2N-CO-, H2NC(=NH)-

-82-
/H2NC)-H2NC(=NS(=0)2NH2)-/ an optionally substituted towewr alkyl-SO2- or
opotionally substituted heterocyclic group-SO1-;
Ri0, R11, R12 and R13 which may be the same or different, represent H-, or a tower
alkyl, and two groups from R10, R11, R12 and R13 may be combined together to
form. oxo (0=);
A represents a nitrogen-containing saturated heterocyclic group, quinolyi or
pyrklin-4-yl; provided that when A represents quinolyi or pyridin-4-yl, R9 is
absent; and,
n represents 0,1 or 2), or a pharmaceutically acceptable salt thereof.
17 The pharmaceutical composition as claimed in claim 15 or 16, which is a
therapeutic agent for neuropathic pain.
18 The pharmaceutical composition as claimed in claim 17 which is a therapeutic
agent for diabetic neuropathic pain.

The invention provides a novel nitrogen-containing heterocyclic derivative
having 2,6-disubstituted styryl and a pharmaceutically acceptable salt thereof, and a
pharmaceutical composition comprising the nitrogen-containing heterocyclic
derivative and a pharmaceutically acceptable salt thereof, in particular, a
pharmaceutical composition effective as a sodium channel inhibitor, having an
excellent analgesic action especially on neuropathic pain with minimized side
effects.

Documents:

1977-kolnp-2005-granted-abstract.pdf

1977-kolnp-2005-granted-claims.pdf

1977-kolnp-2005-granted-correspondence.pdf

1977-kolnp-2005-granted-description (complete).pdf

1977-kolnp-2005-granted-examination report.pdf

1977-kolnp-2005-granted-form 1.pdf

1977-kolnp-2005-granted-form 18.pdf

1977-kolnp-2005-granted-form 2.pdf

1977-kolnp-2005-granted-form 26.pdf

1977-kolnp-2005-granted-form 3.pdf

1977-kolnp-2005-granted-reply to examination report.pdf

1977-kolnp-2005-granted-translated copy of priority document.pdf

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Patent Number

226428

Indian Patent Application Number

1977/KOLNP/2005

PG Journal Number

51/2008

Publication Date

19-Dec-2008

Grant Date

17-Dec-2008

Date of Filing

06-Oct-2005

Name of Patentee

ASTELLAS PHARMA INC.

Applicant Address

3-11, NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411

Inventors:

#	Inventor's Name	Inventor's Address
1	KAZUMI KIKUCHI	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
2	MAKOTO OKU	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
3	JIRO FUJIYASU	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
4	NORIO ASAI	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
5	TOSHIHIRO WATANABE	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
6	YUKINORI NAGAKURA	C/O ASTELLAS PHARMA INC., 3-11 NIHONBASHI-HONCHO 2-CHOME, CHUO-KU, TOKYO 103-8411
7	HIROSHI TOMIYAMA	C/O KOTOBUKI PHARMACEUTICAL CO., LTD., 6351, OAZA-SAKAKI, SAKAKI-MACHI, HANISHINA-GUN, NAGANO 389-0697
8	MOTOHARU SONEGAWA	C/O KOTOBUKI PHARMACEUTICAL CO., LTD., 6351, OAZA-SAKAKI, SAKAKI-MACHI, HANISHINA-GUN, NAGANO 389-0697
9	YOSHINORI IWAI	C/O KOTOBUKI PHARMACEUTICAL CO., LTD., 6351, OAZA-SAKAKI, SAKAKI-MACHI, HANISHINA-GUN, NAGANO 389-0697
10	KAZUO TOKUZAKI	C/O KOTOBUKI PHARMACEUTICAL CO., LTD., 6351, OAZA-SAKAKI, SAKAKI-MACHI, HANISHINA-GUN, NAGANO 389-0697

PCT International Classification Number

C07D 207/06

PCT International Application Number

PCT/JP2004/002842

PCT International Filing date

2004-03-05

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	2003-061758	2003-03-07	Japan