Title of Invention

A NOVEL PROCESS FOR THE PREPARATION OF N-METHYL-N-[(IS)]-1-PHENYL-2-((3S))-3-HYDROXYPYRROLIDIN-1-YL)ETHYL]-2,2-DIPHENYLACETAMIDE

Abstract The invention relates to a novel process for the preparation of N-methyl-N-[(1S)- 1-phenyl-2-((3S)-3-hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide or N- methyl-N-[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-yl)ethyl]-2,2- diphenylacetamide, and the novel compounds N-methyl-N-[(1S)-1-phenyl-2- ((3S)-3-hydroxypyrrolidin-1-yl)ethane] and N-methyl-N[(1R)-1-phenyl-2-((3R)-3- hydroxypyrrolidin-1-yl) ethane], which are prepared as intermediates.
Full Text FIELD OF INVENTION
The invention relates to a novel process for preparing N-methyl-N-[(lS)-1-
phenyl-2-((3S)-3- hydroxypyrrolidin-1-yl) ethyl]-2, 2-di-phenylacetamide or N-
methyl-N-[(lR)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-yl)ethyl]-2,2-
diphenylacetamide, and the novel compounds N-methyl-N-[(lS)-1-phenyl-2-
((3S)-3-hydroxypyrrolidin-1-yl) ethane] and N-methyl-N-[(lR)-1-phenyl-2-((3R)-
3-hydroxypyrrolidin-1-yl)-ethane], which are formed as intermediates in this
process.
BACKGROUND OF INVENTION
As described by Barber et al. (BJ. Pharmacol. (1994), 113, 1317-1327), both the
compound N-methyl-N-[(lS)-1-phenyl-2-(3S)-3-hydroxypyrrolidin-1-yl) ethyl]-
2,2-diphenylacetamide and its physiologically tolerable salts have valuable
pharmacological properties such as an analgesic, anti-inflammatory and
aquaretic action, so that they are particularly suitable for the production of
medicaments.

It has been found, as described in the Patent Application DE 1 95 23 502 or EP
752 246, that this compound is a particularly efficacious compound which is
suitable as a medicament for the treatment of inflammatory intestinal disorders
in a very particular manner. In particular, this compound is employable and
efficacious in this indication, since it simultaneously alleviates the pain associated
with this disorder and, in the acute case of an intestinal occlusion threatening or
produced due to the inflammatory intestinal disorder, again normalizes or sets in
motion the motor response of the intestine without producing noticeable side
effects. Moreover, the compound can be employed in non-inflammatory intestinal
disorders such as IBS (irritable bowel syndrome).

The Patent Applications DE 40 34 785 Al and DE
42 15 213 Al or EP 0 569 802 Al describe the
preparation of N-methyl-N-[(1S)-1-phenyl-2-((3S)-3-
hydroxypyrrolidin-1-yl)ethyl]-2, 2-diphenylacetamide by
reaction of (2S)-2-N-carboxyethyl-2-phenylglycin-
N,N-[(3S)-3-hydroxytetramethylamide with diphenylacetyl
chloride. As described in DE 42 15 213, the starting
compound (2S)-2-N-carboxyethyl-2-phenylglycin-N,N-
[(3S)-3-hydroxytetramethyleneamide, also known as (1S)-
[1-N-methylamino-1-phenyl-2-{(3S)-3-hydroxypyrrol-
idino)ethane can be prepared by reacting (1S)-1-amino-
l-phenyl-2-chloroethane with (3S)-3-hydroxypyrrolidine
and then methylating with methyl iodide. The problems
of this preparation method, however, are the solubility
of the starting products and that following the
synthesis the racemic product mixture obtained, which
is contaminated by by-products, has to be laboriously
separated. The process known until now for the
preparation of N-methyl-N-[(1S)-1-phenyl-2-((3S)-3-
hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide is
therefore laborious and expensive and results in low
yields based on the starting compounds employed.
It was therefore the object of the present
invention to make available a process, which can be
carried out in a simple manner and economically, for
the preparation of N-methyl-N-[(1S)-1-phenyl-2-((3S)-3-
hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide or,
when using the enantiomeric starting materials, of N-
methyl-N-[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-
yl)ethyl]-2,2-diphenylacetamide, which starts from
economical, readily soluble starting materials which
result in a product which is as enantiomerically pure
as possible, which can then be isolated and purified in
a simple manner.
The object is achieved by a process according
to Claim 1, either the previously unknown compound N-
methyl-N-[(1S)-1-phenyl-2-((3S)-3-hydroxypyrrolidin-1-
yl)ethane] being used as a novel intermediate for the
preparation of N-methyl-N-[(1S)-1-phenyl-2-((3S)-3-

hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide or
N-methyl-N-[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-
1-yl)ethane] being used as a novel intermediate for the
preparation of N-methyl-N-[(1R)-1-phenyl-2-((3R)-3-
hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide.
It has been found that compounds of the formula
(III)

in which R and R2 have the following meanings,
R is H, OR1 or SR1,
R1 is A, aryl, heteroaryl,- Si(R3)3 or COR3,
R2 is H, A, aryl, heteroaryl and Si(R3)3 or COR3,
R3 is H, A, aryl or heteroaryl,
A is a straight-chain or branched alkyl radical
having 1 to 6 C atoms,
can be prepared in high yields and in enantiomerically
pure form by amidically coupling, depending on the
final product desired, (3S)-3-hydroxypyrrolidines or
(3R)-3-hydroxypyrrolidines of the formula (II)

in which
R2 is H, A, aryl, heteroaryl and Si(R3)3 or COR3
and
R3 is H, A, aryl or heteroaryl
or their salts, formed with HCl, HBr, HI, H2SO4, H3PO4
or suitable organic acids,
with appropriate (S)- or (R)-enantiomeric forms of N-
substituted phenylglycines of the formula (I)



in which
R is H, OR1 or SR1,
R1 is A, aryl, heteroaryl, Si(R3)3 or COR3,
R3 is H, A, aryl or heteroaryl,
M is H or a cation from the group consisting of
alkali metal, alkaline earth metal, ammonium or
alkylammonium.

Alkyl has 1 to 6, preferably 1, 2, 3 or 4, C
atoms. Alkyl is preferably methyl, furthermore ethyl,
propyl, isopropyl, butyl, isobutyl, sec-butyl or tert-
butyl, furthermore also pentyl, 1-, 2- or 3—
methylbutyl, 1,1-, 1,2- or 2,2-dimethylpropyl, 1-
ethylpropyl, hexyl, 1-, 2-, 3- or 4-methylpentyl, 1,1-,
1,2-, 1,3-, 2,2-, 2,3- or 3,3-dimethylbutyl, 1- or 2-
ethylbutyl, 1-ethyl-1-methylpropyl, l-ethyl-2-
meth.ylpropyl, 1,1,2- or 1, 2, 2-trimethylpropyl.
Aryl is preferably unsubstituted phenyls or
phenyl which is mono- or disubstituted by Hal,OA or
alkyl, furthermore, for example, biphenyl or naphthyl.
Heteroaryl is preferably, for example, furanyl,
thiophenyl, pyridinyl, pyrrolyl or thiazolyl.
Si(R3}3 is preferably, for example, Si(CH3)3.
COR3 is preferably, for example, acetyl or
benzoyl.
R is preferably, in particular, for example,
methoxy or ethoxy.
R1 is in particular, for example, methyl,
ethyl, propyl, butyl, phenyl, Si(CH3-)3 or acetyl.
R2 is, in particular, for example, H, tert-
butyl, Si(CH3)3, acetyl, benzyl or benzoyl, very
particularly preferably it is H.

The amides of the formula (III) prepared can be
converted in a simple manner reductively, if
appropriate by removal of the protective group from the
hydroxyl group of the pyrrolidine in N-methyl-N-[(1S)-
l-phenyl-2-((3S)-3-hydroxypyrrolidin-1-yl)ethane] or N-
methyl-N-[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-
yl) ethane] of the formula (IV).
By reaction with activated carboxylic acids of
the formula (V)

in which
R4 is F, Cl, Br, I, OA or O-CO-
it is possible to obtain from the free bases of the
compounds of the formula (IV)

or from their salts, formed with HC1, HBr, HI, H2SO4,
H3PO4 or suitable organic acids, the enantiomeric
compounds of the formula (VI)

in pure form. Preferably, these compounds are prepared
as hydrochlorides, the compound N-methyl-N-[(1S)-1-


phenyi-2- ( (3S) -3-hydroxypyrrolidin-1-yl) ethyl] -2,2-di-
phenylacetamide being the known form EMD 61753; but the
corresponding salts with the other abovementioned acids
can also be prepared analogously.
In particular, N-methyl-N-[(1S)-1-phenyl-2-
{{3S} -3-hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacet-
amide can be prepared by the last reaction with
diphenylacetyl chloride.
The compounds of the formula (IV) synthesized
as intermediates can generally be obtained by reaction
of compounds of the formula (I) with those of the
formula (II). Preferably, compounds of the formula (I)
are used in this reaction in which R has the meaning
OR1 where R1 is A, aryl, hetefoaryl, Si(R3)3 or COR2 and
R2 is H, alkyl, aryl or heteroalkyl, having the
preferred meanings indicated above. Surprisingly, in
contrast to the use of the corresponding formyl
compound, enantiomerically pure reaction products of
the formula (III) are obtained. In this manner, the
resolution of the racemate can advantageously be
omitted.
The reaction of the compounds -{I) and (II) can
be carried out in any desired aprotic solvent.
Particularly suitable solvents are polar aprotic
solvents from the group consisting of diethylether,
petroleum ether, acetone, nitrobenzene, dimethyl-
formamide, dimethyl sulphoxide or other corresponding
solvents. In this connection, the starting materials
are taken up in sufficient solvent such that a 10 to 30
percent solution is obtained. Preferably, the reaction
is carried out in tetrahydrofuran as a solvent.
The reactions of the compounds (I) and (II) are
carried out under suitable conditions at temperatures
between 0 and 50°C. Particularly good results, however,
are achieved at room temperatures between 20 and 30°C
and at normal pressure.
For the activation of the starting materials,
the presence of an auxiliary reagent is necessary.
These can be auxiliaries which are also used as peptide

coupling reagents. Suitable compounds are those such
as, for example, phosphorus oxytrichloride, phosphorus
halides of valency III and V, phosgene,
dicyclohexylcarbodiimide, the triburtylammonium salt of
pyridine, phenyl dichlorophosphate, 2-chloro-l,2,3-
trinitrobenzene, phosphoric acid esters, chloro-
sulphonyl isocyanate, CH3SO2Cl- (C2H5)3N, (C6H5)3P-CCl4-
(C2H5)3N, N,N'-carbonyldiimidazole, N-(alkylcarbonyl)-
imidazoles, acid anhydrides or acid chlorides and in
particular alkyl chloroformates, such as ethyl
chloroformate. Other suitable auxiliary reagents are
described in various reference books, such as, for
example, in C. Ferri "Reaktionen der organischen
Synthese" ["Reactions of Organic Synthesis"]; R. C.
Larock "Comprehensive Organic Transformations; A Guide
to Functional Group Preparations", Verlag Chemie, 1989.
Furthermore, the presence of a base , is
necessary. Suitable bases can likewise be inferred from
the abovementioned reference books. Such bases are, for
example, tertiary amines, such as, for example,
triethylamine. However, inorganic bases can also be
added. Suitable inorganic bases are, in particular,
carbonates. When using the alkyl metal hydroxides, such
as NaOH or KOH, attention is particularly to be paid to
exact addition, since otherwise undesired side
reactions occur. For simplification of the work-up,
however, it is also possible to employ the
hydroxypyrrolidine in an excess., so that it acts as a
base itself.
The work-up of the reaction product (III)
obtained ca'n be carried out from the filtrate after
filtering off the precipitate obtained using customary
laboratory methods. For example, a customary and
suitable method consists in distilling off the solvent,
taking up the crude product again in an organic
solvent, extracting the solution obtained with water a
number of times, distilling off the solvent again and
recrystallizing the product obtained by
recrystallization from a suitable solvent, such as, for

example, from methanol. However, other working-up
variants known to the person skilled in the art are
also possible, such as, for example, those which
additionally include a chromatographic purification.
Depending on the reaction conditions, the
reaction product (III) is obtained from a water-
containing solvent mixture as a free base or as an acid
addition salt of the acids HCl, HBr, HI, H2SO4 or of an
organic carboxylic acid. In the latter cases, the
isolation can be carried out after the phase separation
according to customary laboratory methods.
Suitable organic carboxylic acids which can be
used are, in particular, aliphatic, alicyclic,
araliphatic, aromatic or heterocyclic mono- or
polybasic carboxylic, sulphonic or sulphuric acids,
e.g. formic acid, acetic acid, propionic acid, pivalic
acid, diethylacetic acid, malonic acid, succinnic acid,
pimelic acid, fumaric acid, maleic acid, lactic acid,
tartaric acid, malic acid, citric acid, gluconic acid,
ascorbic acid, nicotinic acid, isonicotinic acid,
methane- or ethanesulphonic acid, ethanedisulphonic
acid, 2-hydroxyethanesulphonic acid, benzenesulphonic
acid, p-toluenesulphonic acid, naphthalene -mono- and
-disulphonic acids, lauryl sulphuric acid.
The compounds of the formula (III) are reduced
under a protective gas atmosphere, e.g. under a
nitrogen atmosphere, in the presence of a hydride
transfer reagent. Suitable hydride transfer reagents
are those from the group consisting of the metal
aluminium hydrides, preferably lithium aluminium
hydride, metal alkoxyaluminium hydrides, such as, for
example, Li triethoxyaluminium hydride, metal
borohydrides, preferably NaBH4, or borane, the presence
of a Lewis acid additionally being necessary, such as,
for example, boron trifluoride.
The reduction is preferably carried out in a
polar aprotic and hydride-inert solvent. Suitable
solvents are the same as already mentioned above.

Particularly suitable solvents are, for example,
diethylether or tetrahydrofuran.
To carry out the hydrogenation, a compound of
the formula (III) is dissolved in a suitable solvent
and added with warming to a solution which contains the
hydride transfer reagent in equimolar amounts or in a
small excess. However, it is also possible to introduce
the starting compound to be hydrogenated and to add the
hydrogenation reagent in an appropriate amount in a
suitable manner such that a reaction mixture is
obtained in which the starting material has a
concentration of 10 to 25% by weight, based on the
solvent. To complete the reaction, the reaction mixture
is stirred under reflux conditions for a number of
hours. The reaction solution is then processed
according to methods known to the person skilled in the
art, by decomposing, inter alia, by addition of a
solvent mixture consisting of a proton-yielding and an
aprotic solvent, the excess of hydride transfer reagent
and liberating the reaction product. Suitable proton-
yielding solvents are, for example, water or alcohols
such as ethanol or methanol. 'Suitable aprotic solvents
are all polar aprotic solvents already mentioned above,
in particular tetrahydrofuran. The latter is preferably
employed, since it is obtainable industrially as an
anhydrous product.
Product work-up can be carried out after phase
separation according to customary laboratory methods.
The crude product obtained can be worked up by
crystallization methods or, for work-up, it is taken
up, for example, in an organic water-immiscible solvent
and treated with an excess of an inorganic acid,
preferably hydrochloric acid. The salt formed in this
manner can then be separated off in crystalline form.
The further reaction of N-methyl-N-[(1S)-1-
phenyl-2-((3S)-3-hydroxypyrrolidin-1-yl)ethane or its
dihydrochloride with a suitable diphenyl acetic acid
derivative, preferably the acid chloride, to give the
desired final product N-methyl-N-[(1S)-1-phenyl-2-

( (3S)-3-hydroxypyrrolidin-1-yl)ethyl]-2 2-diphenylacet-
amide (formula VI, EMD 61753) is carried out according
to methods such as are described in DE-Al-40 34 785 and
DE-Al-42 15 213 or EP 0 569 802 Al.
" The examples given below are given for
illustration of the present invention, but cannot be,
used to restrict the claimed invention thereto, since
different variations of the examples are possible and
lead to the desired product N-methyl-N-[(1S)-1-phenyl-
2-((3S) —3-hydroxypyrrolidin-1-yl)ethane [formula (IV)],
which can be used as- an intermediate for the
preparation of N-methyl-N-[(1S)-1-phenyl-2-((3S)-3-
hydroxypyrrolidin-1-yl)ethyl]-2, 2-diphenylacetamide.
EXAMPLES
N-Substituted (2S)-2-phenylglycine-N,N-[(3S)-3-
hydroxytetramethyleneamides] of the formula III from
(2S)-phenylglycines of the formula I
Example 1
(2S) -N-Formyl-2-phenylglycine-N,N-[ (3S) -3-hydroxytetra-
methyleneamide
From (2S)-N-formyl-2-phenylglycine (obtainable
from (S)-(+)-alpha-aminophenylacetic acid and acetic
anhydride/formic acid, e.g. according to Huszthy,
Peter; Oue, Masatoshi; Bradshaw, Jerald S.; Zhu, Cheng
Y.; Wang, Tingmin; et al., J. Org. Chem., EN, 57 (20)
[1992] 5383-5394)
and
(3S)-3-hydroxypyrrolidine (obtainable from commercial
(S)-1-benzyl-3-pyrrolidinole, e.g. according to Bhat,
Krishna L.; Flanagan, Denise M.; Joullie, Madeleine M. ,
Synth. Commun., EN, 15 (7) [1985] 587-598 or Naylor,
Alan; Judd, Duncan B.; Scopes, David I. C; Hayes, Ann
G.; Birch, Philip J., J. Med. Chem., EN, 37 (14) [1994]
2138-2144):
Under a nitrogen atmosphere, 4.8 ml of ethyl
chloroformate in 10 ml of tetrahydrofuran are added

with stirring to 9 g of (2S)-N-formyl-2-phenylglycine
and 5.5 ml of N-methylmorpholine in 250 ml of THF at
-15°C and, after a waiting time of 10 min, a solution
of 6.2 g of (3S)-3-hydroxypyrrolidine hydrochloride and
7 ml of triethylamine in 50 ml of dimethylformamide.
After stirring for 18 hours, the precipitate obtained
is separated off and resultant (2S)-N-formyl-2-
phenylglycine-N,N-[(3S)-3-hydroxytetramethyleneamide is
isolated from the filtrate by concentration using
customary laboratory methods, and a subsequent
chromatographic purification.
1H-NMR: D6-DMSO; 3.0-3.8 (m) , 4.25 (d) , 5.0 (s,br), 5.7
(dd), 7.4 (ArH), 8.0 (ArH), 8.8 (CHO):
MS-FAB: (M+l)+ 221, 205;
Crystals m.p.: 97-101°C;
[a]D20 = +208°, c = 1 in methanol.
Example 2
(2S)-N-Carboxybenzyl-2-phenylqlycine-N,N-[ (3S)-3-
hydroxytetramethyleneamide
From (2S)-N-carboxybenzyl-2-phenylglycine (from
(S)-(+)-alpha-aminophenylacetic acid and benzyl
chlorocarbonate, for example, according to Jones,
Raymond CF; Turner, Ian; Howard, Kevin J., Tetrahedron
Lett., 34 (39) [1993] 6329-6332)
and
(3S)-3-hydroxypyrrolidine (obtainable from commercial
(S)-1-benzyl-3-pyrrolidinole, for example, according to
Bhat, Krishna L.; Flanagan, Denise M.; Joullie,
Madeleine M., Synth. Commun., EN, 15 (7) [1985] 587-598
or Naylor, Alan; Judd, Duncan B.; Scopes,- David I. C;
Hayes, Ann G.; Birch, Philip J., J. Med. Chem., EN, 37
(14) [1994] 2138-2144} :
Under a nitrogen atmosphere, 14.3 g of (2S)-N-
carboxybenzyl-2-phenylglycine in 100 ml of tetrahydro-
furan are treated in the cold with 5.5 ml of 4-methyl-
morpholine and a solution of 4.8 ml of ethyl
chloroformate and 10 ml of tetrahydrofuran and then

stirred for 30 min. A solution of 4.36 g of (3S)-3-
hydroxypyrrolidine and 10 ml of tetrahydrofuran is then
added. After stirring for 18 hours, the precipitate
obtained is separated off and the (2S)-N-carboxybenzyl-
2-phenylglycine-N,N-[(3S)-3-hydroxytetramethyleneamide
formed is isolated from the filtrate by concentrating
using customary laboratory methods, taking up in an
organic solvent, washing with an aqueous phase,
concentrating again and crystallization.
1H-NMR: D6-DMS0+TFA; 5.1 (s), PhCH2R;
FAB-MS: 355 (M+l)+, 311, 196, 176;
Consistency: Oil;
[α]D20 = +108°, c = 1 in methanol.
Example 3
(2S)-N-Carboxyethyl-2-phenylglycine-N,N-[{3S)-3-
hydroxytetramethyleneamide
3.a)
From (2S)-N-carboxyethyl-2-phenylglycine (from
(S)-(+)-alpha-aminophenylacetic acid and ethyl
chlorocarbonate, for example, according to Bodurow, C.
C; Boyer, B. D.; Brennan, J,; Bunnell, C. A.; Burks,
J. E.; et al., Tetrahedron Lett., EN, 30 (18) [198 9}
2321-2324)
and »
(33)-3-hydroxypyrrolidine (obtainable from commercial
(S)-1-benzyl-3-pyrrolidinole, for example, according to
Bhat, Krishna L.; Flanagan, Denise M.; Joullie,
Madeleine M., Synth. Commun., EN, 15 (7) [1985] 587-598
or Naylor, Alan; Judd, Duncan B.; Scopes, David I. C;
Hayes, Ann G.; Birch, Philip J., J. Med. Chem., EN, 37
(14) [1994] 2138-2144) :
under a nitrogen atmosphere, 16.7 g of (2S)-N-
carboxyethyl-2-phenylglycine are treated in the cold
with 0.3 ml of 4-methylmcrphclinc and a solution of
7.1 ml of ethyl chloroformate and 20 ml of
tetrahydrofuran and then stirred for 60 min. A solution

of 6.5 g of (3S)-3-hydroxypyrrolidine and 30 ml of
tetrahydrofuran is then added. After stirring for 18
hours, the precipitate obtained is separated off and
resultant (2S)-N-carboxyethyl-2-phenylglycine-N,N-
[ (3S)-3-hydroxytetramethyleneamide is isolated from the
filtrate by concentrating using customary laboratory
methods, taking up in an organic solvent, washing with
an aqueous phase, concentrating again and
crystallization.
3.b)
From (2S)-N-carboxyethyl-2-phenylglycine (see
above) and (3S)-3-hydroxypyrrolidine hydrochloride
(commercially obtainable): a mixture of 24 g of (2S)-N-
carboxyethyl-2-phenylglycine with 10 g of
methylmorpholine in 100 ml of THF is added at about
-10°C to 11 g of ethyl chloroformate in 100 ml of THF.
After a stirring phase, this is followed by a mixture
of 12 g of (3S)-3-hydroxypyrrolidine hydrochloride in
10 ml of deionized water and a mixture of 10 g of
methylmorpholine in 20 ml of THF. After stirring for a
number of hours and phase separation, the (2S)-N-
carboxyethyl-2-phenylglycine-N,N-[(3S)-3-hydroxytetra-
methyleneamide is isolated using customary laboratory
methods by concentrating, taking up in an organic
solvent, washing with an aqueous phase, concentrating
it again and crystallization.
The analytical data for the variants 3a and 3b
correspond:
1H-NMR: D6-DMSO; 1.2 (t) , 3-3.8 (m, br), 4.05 (q), 4.25
(s,br), 7.25-7.45 (m) ;
MS: 293 (M+1), 247, 178, 106;
Crystals m.p.: 124-126°C;
[α]D20 = +137°C = 1 in methanol.
N-Methyl-N-[(1S)-1-phenyl-2-((3S)-3-hydroxypyrrolidin-
1-yl)ethane of the formula IV

Example 4
N-Methyl-N- [(1S)-1-phenyl-2-((3S)-3-hydroxypyrrolidin-
1-yl)ethane =
l-[(3S)-3-Hydroxypyrrolidin-1-yl]-(2S)-2-methylamino-2-
phenylethane
Under nitrogen, 2200 ml of a 1.08 molar lithium
aluminium hydride-tetrahydrofuran solution are gently
warmed and a solution of 264 g of (2S)-N-carboxyethyl-
2-phenylglycine-N,N-[(3S)-3-hydroxytetramethyleneamide]
and 1400 ml of tetrahydrofuran are added with stirring.
After the end of the addition, the mixture is refluxed
for 3 hours and the cooled reaction solution is
hydrolyzed by means of a water/tetrahydrofuran mixture.
After sodium carbonate treatment and removal of
inorganic constituents, the product is isolated from
the filtrate using customary laboratory methods. The
oily crude product forms a solid after purification by
means of crystallization or chromatography.
1H-NMR: D6-DMS0; 2.1-3.1 (m) , .3.6 (dd) , 4.3 (m) , 7.15-
7.35 (m); :
MS: 220 (M+) , 205, 120, 100, 91;
Appearance: Yellowish oil which crystallizes depending
on the batch;
[a]D20 = +66.8°; c = 0.0938 g in 10 ml of methanol.
Example 5
N-Methyl-N-[(1S)-1-phenyl-2-((3S)-3-hydroxypyrrolidin-
1-yl)ethane dihydrochloride =
1-[(3S)-3-Hydroxypyrrolidin-1-ylj-(2S)-2-methylamino-2-
phenylethane dihydrochloride
Under nitrogen, 2200 ml of a 1.08 molar lithium
aluminium hydride-tetrahydrofuran solution are gently
warmed and a solution of 264 g of (23)-N-carboxyethyl-
2-phenylglycine-N, N-[(3S)-3-hydroxytetramethyleneamide]
and 1400 ml of tetrahydrofuran are added with stirring.

After the end of the addition, the mixture is refluxed
for a further 3 hours, then cooled and the reaction
solution is hydrolyzed by means of a mixture of 80 ml
of water and 400 ml of tetrahydrofuran. After sodium
carbonate treatment and removal of inorganic
constituents, the product is isolated from the filtrate
using customary laboratory methods. The oily crude
product is taken up in an organic, water-immiscible
solvent and treated with an excess of hydrochloric
acid. The crystalline product is isolated and dried.
1H-NMR: D6-DMSO; 3.4 (m) , 3.8 (m) , 4.2 (m) , 4.4 (m) ,
4.9 (m), 7.5 and 7.8 (ArH);
Melting point: 240-242°C;
[a]D20 = -22.4°; c = 1 in water.


We Claim:
1. A process for preparing N-methyl-N-[(1S)-1-phenyl-2-((3S))-3-
hydroxypyrrolidin-1-yl)ethyl]-2, -diphenylacetamide or N-methyl-N-
[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-yl)ethyl]-2,
-diphenylacetamide, characterized in that
a) an N-substituted phenylglycine derivative of the formula I

in which
R is OR1 or SR1,
R1 is A, aryl, heteroaryl, Si (R3)3, COR3 or benzyl,
R3 is H, A, aryl, heteroaryl

A is a straight-chain or branched alkyl radical having 1 to 6 carbon atoms
M is H or a cation from the group consisting of alkali metal, alkaline earth metal,
ammonium or alkylammonium is reacted with a compound of the formula (II),


in which R2 is H, A, aryl, heteroaryl, Si(R3)3, COR3 and
R3 is H, A, aryl, heteroaryl
or an acid addition salt of the compound of the formula II, of the acids HCI, HBr,
HI, H2SO4, H3PO4 or an organic carboxylic acid, to give a compound of the
in which R and R2 are as defined above,
formula III


b) which is subsequently reduced to a compound of the formula IV

which is optionally converted into a corresponding acid addition salt of the acids
HCI, HBr, HI, H2SO4, H3PO4 or into a salt of an organic carboxylic acid, and
c) the resulting compound of the formula IV is reacted with an activated
carboxylic acid of the formula (V)


in which
R4 is F, CI, Br, I, OA, O-CO-A, to give the compound of the formula VI

which is optionally converted with an inorganic acid from the group consisting of
HCI , HBr, HI, sulphuric acid, sulphaminic acid, nitric acid, phosphoric acid,
orthophosphoric acid, or with an organic acid, into the corresponding acid
addition salt, where the starting materials employed for step a) depend on the
enantiomer desired as end product.
2. The process as claimed in claim 1, wherein compounds of the formula (I) are
employed in which R has the meating OR1 where R1 is A, aryl, heteroaryl,
SI(R3)3, COR3 and R3 is H, A, aryl, heteroaryl.

3. The process as claimed in claim 1 or 2, wherein the reaction of the
compounds (I) and (II) is carried out in an aprotic, preferably polar aprotic,
solvent at a temperature of from 0 to 50°C, preferably at temperatures between
20 and 30°C.
4. The process as claimed in one or more of claims 1 to 3, wherein the reaction
of the compounds (I) and (III) is carried out in a solvent from the group
consisting of diethyl ether, petroleum ether, acetone, nitrobenzene,
dimethylformamide, dimethyl sulphoxide, tetrahydrofuran, where the starting
materials in the solvent are present in a concentration of from 10 to 30%.
5. The process as claimed in one or more of claims 1 to 4, wherein the reaction
of the compounds (I) and (II) is carried out in the presence of an auxiliary
reagent from the group consisting of phosphorus oxytrichloride, phosphorus
halides of the valency III and V, phosgene, dicyclohexylcarbodimide,
tributylammonium salt of pyridine, phenyl dichlorophosphate, 2-chloro-l,2,3-
trinitrobenzene, phosphoric acid esters, chlorosulphonyl isocyanate, CH3SO2CI-
(C2H5)3N, (C6H5)3 P-CCl4-(C2H5)3N,N,N- carbonyldiimidazoles, N-(alkylcarbonyl)
imidazoles, acetic anhydride, acetyl chloride and ethyl chloroformate and an
organic or inorganic base.

6. The process as claimed in one or more of claims 1 to 5, wherein the reaction
of the compounds (I) and (II) is carried out in the presence of a base from the
group consisting of triethylamine, sodium carbonate, potassium carbonate,
calcium carbonate, NaOH, KOH.
7. The process as claimed in one or more of claims 1 to 6, wherein the reduction
of the compounds of the formula (III) is carried out in the presence of a hydride
transfer reagent from the group consisting of the metal aluminium hydrides,
preferably lithium aluminium hydride, the metal alkoxyaluminohydrides,
preferably lithium triethoxyaluminohydrides, the metal borohydrides, preferably
NaBH4, or borane, and, if appropriate, in the presence of a Lewis acid, such as
boron trifluoride, in a polar aprotic solvent from the group consisting of diethyl
ether, petroleum ether, acetone, nitrobenzene, dimethyllformamide, dimethyl
sulphoxide, tetrahydrofuran.
8. The process as claimed in claims 1 to 7, wherein a compound of the formula
(III) as starting material is dissolved in a solvent in a concentration of from 10 to
25% and the hydrogenation product is set free by addition of a proton-donating
solvent in a mixture with an aprotic solvent.

9. The process as claimed in claims 1 to 8, wherein the compound N- methyl -
N- {lS-1-phenyl - 2- ({3S-hydroxypyrrolidin - 1- yl) ethyl) -2, 2-
diphenylacetamide is used for the treatment of non-inflammatory intestinal
disorders.
10. The process as claimed in claim 9, wherein the non-inflammatory disorder is
irritable bowel syndrome.
Dated this 16th day October 2000

The invention relates to a novel process for the preparation of N-methyl-N-[(1S)-
1-phenyl-2-((3S)-3-hydroxypyrrolidin-1-yl)ethyl]-2,2-diphenylacetamide or N-
methyl-N-[(1R)-1-phenyl-2-((3R)-3-hydroxypyrrolidin-1-yl)ethyl]-2,2-
diphenylacetamide, and the novel compounds N-methyl-N-[(1S)-1-phenyl-2-
((3S)-3-hydroxypyrrolidin-1-yl)ethane] and N-methyl-N[(1R)-1-phenyl-2-((3R)-3-
hydroxypyrrolidin-1-yl) ethane], which are prepared as intermediates.

Documents:

IN-PCT-2000-409-KOL-FORM-27.pdf

in-pct-2000-409-kol-granted-abstract.pdf

in-pct-2000-409-kol-granted-assignment.pdf

in-pct-2000-409-kol-granted-claims.pdf

in-pct-2000-409-kol-granted-correspondence.pdf

in-pct-2000-409-kol-granted-description (complete).pdf

in-pct-2000-409-kol-granted-examination report.pdf

in-pct-2000-409-kol-granted-form 1.pdf

in-pct-2000-409-kol-granted-form 18.pdf

in-pct-2000-409-kol-granted-form 2.pdf

in-pct-2000-409-kol-granted-form 26.pdf

in-pct-2000-409-kol-granted-form 3.pdf

in-pct-2000-409-kol-granted-form 5.pdf

in-pct-2000-409-kol-granted-form 6.pdf

in-pct-2000-409-kol-granted-gpa.pdf

in-pct-2000-409-kol-granted-priority document.pdf

in-pct-2000-409-kol-granted-reply to examination report.pdf

in-pct-2000-409-kol-granted-specification.pdf

in-pct-2000-409-kol-granted-translated copy of priority document.pdf


Patent Number 229495
Indian Patent Application Number IN/PCT/2000/409/KOL
PG Journal Number 08/2009
Publication Date 20-Feb-2009
Grant Date 18-Feb-2009
Date of Filing 16-Oct-2000
Name of Patentee TIOGA PHARMACEUTICALS, INC.
Applicant Address C/O FORWARD VENTURES, 9393 TOWNE CENTRAL DRIVE, SUITE 200, SAN DIEGO, CALIFORNIA
Inventors:
# Inventor's Name Inventor's Address
1 BATHE ANDREAS MERCHSTRASSE 16, D-64283 DARMSTADT
2 HELFERT BERND SCHILLERSTRASSE 1, D-64373 OBER-RAMSTADT
3 ACKERMANN KARI-AUGUST AM PFARRWEONER 40, D-64372 OBER-RAMSTADT
4 GOTTSCHLICH RUDOLF BUCHENWEG 1, D-64354 REINHEIM
5 BUDAK JENS ROSSDORFER STRASSE 45, D-64287 DARMSTADT
PCT International Classification Number C07D 207/12
PCT International Application Number PCT/EP1999/02574
PCT International Filing date 1999-04-16
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 198 27 633.8 1998-06-20 Germany
2 198 17 393.8 1998-04-20 Germany