Title of Invention

"A FUSED TETRAHYDROPYRIDAZINE DIHYDROPYRAZOLE COMPOUNDS OF FORMULA II"

Abstract The present invention relates a fused tetrahydropyridazine and dihydropyrazole compound of the formula: the racemic-diastereomeric mixtures and optical isomers of said compounds
Full Text HETEROCYCLIC COMPOUNDS
This invention relates to dipeptide compounds which are growth hormone
secretagogues and are useful for the treatment and prevention of osteoporosis.
Background of the Invention
Growth hormone (GH), which is secreted from the pituitary gland, stimulates
growth of all tissues of the body that are capable of growing. In addition, growth
hormone is known to have the following basic effects on the metabolic process of the
1. Increased rate of protein synthesis in substantially all cells of the
2. Decreased rate of carbohydrate utilization in cells of the body;
3. Increased mobilization of free fatty acids and use of fatty acids for
energy.
Deficiency in growth hormone results in a variety of medical disorders. In
children, it causes dwarfism. In adults, the consequences of acquired GH deficiency
include profound reduction in lean body mass and concomitant increase in total body
fat, particularly in the truncal region. Decreased skeletal and cardiac muscle mass
and muscle strength lead to a significant reduction in exercise capacity. Bone
density is also reduced. Administration of exogenous growth hormone has been
shown to reverse many of the metabolic changes. Additional benefits of therapy
have included reduction in LDL cholesterol and improved psychological well-being.
In cases where increased levels of growth hormone were desired, the
problem was generally solved by providing exogenous growth hormone or by
administering an agent which stimulated growth hormone production and/or release.
In either case the peptidyl nature of the compound necessitated that it be
administered by injection. Initially the source of growth hormone was the extraction
of the pituitary glands of cadavers. This resulted in an expensive product, and
carried with it the risk that a disease associated with the source of the pituitary gland
could be transmitted to the recipient of the growth hormone (e.g., Jacob-Creutzfeld
disease). Recently, recombinant growth hormone has become available which, while
no longer carrying any risk of disease transmission, is still a very expensive product
which must be given by injection or by a nasal spray.
Most GH deficiencies are caused by defects in GH release, not primary
defects in pituitary synthesis of GH. Therefore, an alternative strategy for
ormaiizing serum GH levels is by stimulating its release from somatotrophs.
Increasing GH secretion can be achieved by stimulating or inhibiting various
neurotransmitter systems in the brain and hypothalamus. As a result, the
development of synthetic growth hormone-releasing agents to stimulate pituitary GH
secretion are being pursued, and may have several advantages over expensive and
inconvenient GH replacement therapy. By acting along physiologic regulatory
pathways, the most desirable agents would stimulate pulsatile GH secretion, and
excessive levels of GH that have been associated with the undesirable side effects
of exogenous GH administration would be avoided by virtue of intact negative
feedback loops.
Physiologic and pharmacologic stimulators of GH secretion include arginine,
L-3,4-dihydroxyphenylalanine (L-DOPA), glucagon, vasopressin, and insulin induced
hypoglycemia, as well as activities such as sleep and exeruse, indirectly cause
growth hormone to be released from the pituitary by acting in some fashion on the
hypothalamus perhaps either to decrease somatostatin secretion or to increase the
secretion of the known secretagogue growth hormone releasing factor (GHRF) or an
unknown endogenous growth hormone-releasing hormone or all of these.
Other compounds have been developed which stimulate the release of
endogenous growth hormone such as analogous peptidyl compounds related to GRF
or the peptides of U.S. Patent 4,411,890. These peptides, while considerably
smaller than growth hormones are still susceptible to various proteases. As with
most peptides, their potential for oral bioavailability is low. WO 94/13696 refers to
certain spiropiperidines and homologues which promote release of growth hormone.
Preferred compounds are of the general structure shown below.
WO 94/11012 refers to certain dipeptides that promote release of growth
hormone. These dipeptides have the general structure
The compounds of WO 94/11012 and WO 94/13696 are reported to be useful
in the treatment of osteoporosis in combination with parathyroid hormone or a
bisphosphonate.
Summary of the Invention
This invention provides compounds of the formula:
(Figure Removed) the racemic-diastereomeric mixtures and optical isomers of said compounds and the
pharmaceutically-acceptable salts and prodrugs thereof.
R4 is hydrogen, (C1-C6)alkyl or (C3-C7)cycloalkyl, or R4 is taken together with R3 and
the carbon atom to which they are attached and form (C5-C7)cycloalkyl, (C5-
C7)cycloalkenyl, a partially saturated or fully saturated 4- to 8-membered ring having
1 to 4 heteroatoms independently selected from the group consisting of oxygen,
sulfur and nitrogen, or is a bicyclic ring system consisting of a partially saturated or
fully saturated 5- or 6-membered ring, fused to a partially saturated, fully unsaturated
or fully saturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
X4 is hydrogen or (CVCeJalkyl or X4 is taken together with R4 and the nitrogen atom
to which X4 is attached and the carbon atom to which R4 is attached and form a five
to seven membered ring;
X5 and X5a are each independently selected from the group consisting of
hydrogen, trifluoromethyl, A1 and optionally substituted (CrC6)alkyl;
the optionally substituted (CrC6)alkyl in the definition of Xs and Xs* is
optionally substituted with a substrtuent selected from the group
consisting of A1, OX2, -SfOUCi-CaJalkyl, -C(O)OX2,
(C3-C7)cycloalkyl, -N(X2)(X2) and -C(O)N(X2)(X2);
or the carbon bearing X5 or Xs forms one or two alkylene bridges with the
nitrogen atom bearing R7 and R8 wherein each alkylene bridge contains 1 to
5 carbon atoms, provided that when one alkylene bridge is formed then X5 or
X53 but not both may be on the carbon atom and R7 or R8 but not both may
be on the nitrogen atom and further provided that when two alkylene bridges
are formed then X5 and X53 cannot be on the carbon atom and R7 and R8
cannot be on the nitrogen atom;
or Xs is taken together with X5and the carbon atom to which they are
attached and form a partially saturated or fully saturated 3- to 7-membered
ring, or a partially saturated or fully saturated 4- to 8-membered ring having 1
to 4 heteroatoms independently selected from the group consisting of
oxygen, sulfur and nitrogen;
or X5 is taken together with X5 and the carbon atom to which they are
attached and form a bicyclic ring system consisting of a partially saturated or
fully saturated 5- or 6-membered ring, optionally having 1 or 2 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and
oxygen, fused to a partially saturated, fully saturated or fully unsaturated 5- or
6-membered ring, optionally having 1 to 4 heteroatoms independently
selected from the group consisting of nitrogen, sulfur and oxygen;
Z1 is a bond, O or N-X2, provided that when a and b are both 0 then Z1 is not
N-X2 or O;
R7 and R8 are independently hydrogen or optionally substituted (C1-C6)alkyl;
where the optionally substituted (CrCeJalkyl in the definition of R7 and R8 is
optionally independently substituted with A1, -C(O)O-(C1-C6)alkyl,
-S(O)m(C1-C6)alkyl, 1 to 5 halogens, 1 to 3 hydroxy, 1 to 3 -O-C(O)(Cr
C10)alkyl or 1 to 3 (CrC6)alkoxy; or
R7 and R8 can be taken together to form -(CH2)rL-(CH2)r-;
where L is C(X2)(X2), S(O)m or N(X2);
A1 for each occurrence is independently (C5-C7)cycloalkenyl, phenyl or a partially
saturated, fulfy saturated or fully unsaturated 4- to 8-membered ring optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
oxygen, sulfur and nitrogen, a bicyclic ring system consisting of a partially saturated,
fully unsaturated or fully saturated 5- or 6-membered ring, optionally having 1 to 4
heteroatoms independently selected from the group consisting of nitrogen, sulfur and
oxygen, fused to a partially saturated, fully saturated or fully unsaturated 5- or 6-
membered ring, optionally having 1 to 4 heteroatoms independently selected from
the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or
optionally both rings if A1 is a bicyclic riny system, with up to three
substituents. each substituent independently selected from the group
consisting of F, Cl, Br, I. OCF3, OCF2H, CF3, CH3l OCH3. -OX6,
-C(O)N(X6)(X6), -C(O)OX6, oxo, (CrC6)alkyl, nitro, cyano, benzyl,
-SfOJmtC^-CeJalkyl, 1H-tetrazol-5-yl, phenyl, phenoxy, phenylalkyloxy,
halophenyl, methylenedioxy, -N(X6)(X6), -N(X6)C(O)(Xe), -SO2N(X*)(Xa),
-N(X6)S02-phenyl, -N(X6)SO2X6. -CONX11X12. -SO2NX11X12, -NX6SO2X12,
~NX8CONX11X12, -NX6SO2NX11X12, -NX6C(O)X12, imidazolyl, thiazolyl or
tetrazolyl, provided that if A1 is optionally substituted with methylenedioxy
then it can only be substituted with one methylenedioxy;
where X11 is hydrogen or optionally substituted (C^-C^alkyl;
the optionally substituted (Ci-C6)alkyl defined for X11 is
optionally independently substituted with phenyl, phenoxy, (Cr
C6)alkoxycarbonyl, -S(O)m(CrC6)alkyl 1 to 5 halogens, 1 to 3
hydroxy, 1 to 3 (d-Cio)alkanoyloxy or 1 to 3 (CrC6)alkoxy;
X12 is hydrogen, (CrC6)alkyl, phenyl, thiazolyl, imidazotyl, furyl or
thienyl, provided that when X12 is not hydrogen, X12 is optionally
substituted with one to three substituents independently selected from
the group consisting of Cl, F, CH3, OCH3l OCF3 and CF3;
or X11 and X12 are taken together to form -(CH2)r-L1-(CH2)r-;
L1 is C(X2)(X2}. O, S(0)m or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted (Cr
C6)alkyl, or optionally substituted (C3-C7)cycloalkyl, where the optionally substituted
(CrC6)alkyl and optionally substituted (C3-C7)cycloalkyl in the definition of X2 are
optionally independently substituted with -S(O)m(CrC6)alkyl, -C(O)OX3, 1 to 5
halogens or 1 to 3 OX3;
X3 for each occurrence is independently hydrogen or (Ci-C6)alkyl;
X6 is independently hydrogen, optionally substituted ((^-CeJalkyl, (C2-C6)halogenated
alkyl, optionally substituted (C3-C7)cycloalkyl, (C3-C7)-halogenatedcycloalkyl, where
optionally substituted (CrC6)alkyl and optionally substituted (C3-C7)cycloalkyl in the
definition of X6 is optionally independently substituted by 1 or 2 (CrC^alkyl,
hydroxyl, (CrC4)alkoxy, carboxyl, CONH2l -SfOJmfCrCeJalkyl, carboxylate (Cr
C4}alkyl ester, or 1H-tetrazol-5-yl; or
when there are two Xs groups on one atom and both X6 are independently (Cr
C6)alkyl, the two (C1-C6)alkyl groups may be optionally joined and, together with the
atom to which the two X6 groups are attached, form a 4- to 9- membered ring
optionally having oxygen, sulfur or NX7;
X7 is hydrogen or (d-C6)alkyl optionally substituted with hydroxyl; and
m for each occurrence is independently 0, 1 or 2;
with the proviso that:
X8 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form
C(O)X6, C(O)X12, SO2X6 or SO2X12; and
when R6 is a bond then L is N(X2) and each r in the definition -(CH2)r-L-(CH2)r- is
independently 2 or 3.
A preferred group of compounds, designated the "A Group", contains those
compounds having the formula I as shown hereinabove wherein X4 is hydrogen; R4
is hydrogen or methyl; R7 is hydrogen or (d-CaJalkyl; R8 is hydrogen or (C^C
optionally substituted with one or two hydroxyl groups;
K x5a
R6js (CH2)a (CH2)b ^,3 Zi is a ^d and a is 0 or 1;
X5 and X53 are each independently hydrogen, triftuoromethyl, phenyl, optionally
substituted (CrC6)alkyi;
where the optionally substituted (CrC6)alkyl is optionally substituted with
OX2, imidazolyl, phenyl, indolyl. p-hydroxyphenyl, (C5-C7)cydoalkyl,
-SfOUd-CeJalkyl, -N(X2)(X2) or -C(O)N(X2)(X2);
or X5 and R7 are taken together to form a (C1-C5)alkylene bridge, and the other
substituents not defined for the "A Group" compounds are as defined for formula (I)
hereinabove.
A group of compounds, which is preferred among the "A Group" of
compounds, designated the "B Group", contains those compounds of the "A Group",
having the formula I as shown hereinabove, wherein b is 0; Xs and X5" are each
independently hydrogen, (d-C3)alkyl or hydroxy(C1-C3)alkyl; R3 is selected from the
group consisting of 1-indolyl-CH2-, 2-indolyl-CH2-, 3-indolyl-CH2-, 1-naphthyl-CH2-, 2-
naphthyl-CH2-, 1-benzimidazolyl-CH2-, 2-benzimidazolyl-CH2-, phenyHCrC^alkyl-,
2-pyridyl-(C1-C4)alkyl-, 3-pyridyl-(C1-C4)alkyl-, 4-pyridyl-(CrC4)alkyl-, phenyl-CH2-SCH2-,
thienyl-(C1-C4)alkyl-, phenyl-(C0-C3)alkyl-O-CH2-, phenyl-CH2-O-phenyl-CH2-,
and 3-benzothienyl-CH2-;
where the aryl portion(s) of the groups defined for R3 are optionally
substituted with one to three substituents, each substituent being
independently selected from the group consisting of methylenedioxy, F, Cl,
CH3. OCH3l OCF3, OCF2H and CF3.
A group of compounds, which is preferred among the "B Group" of
compounds, designated the "C Group", contain those compounds of the *B Group",
having the formula I as shown hereinabove, wherein R4 is hydrogen; a is 0; n is 1 or
2; w is 0 or 1; X5 and X5" are each independently, hydrogen, methyl or
hydroxymethyl, provided that when X5 is hydrogen then X5* is not hydrogen;
R7 and R8 are each hydrogen; and
R3 is phenyl-CH2-O-CH2-, phenyl-CH2-S-CHr, 1-naphthyl-CH2-, 2-naphthyl-CH2-,
phenyl-(CH2)3- or 3-indolyl-CH2-;
where the aryl portion of the groups defined for R3 is optionally substituted
with one to three substituents, each substituent being independently selected
from the group consisting of fluoro, chloro, methyl, OCH3, OCF2H, OCF3 and
A group of compounds, which is preferred among the "C Group* of
compounds, designated the "D Group", contains those compounds of the "C Group",
having the formula I as shown hereinabove, wherein R1 is -(CH2)|-A1,
-(CH2)q-(C3-C7)cycloalkyl or (C,-C10)alkyl;
where A1 in the definition of R1 is optionally substituted with one to three
substituents, each substituent being independently selected from the group
consisting of fluoro, chloro, methyl, OCH3l OCF2H, OCF3 and CF3;
the cycloalkyl and alkyl groups in the definition of R1 are optionally substituted
with (CrC4)alkyl, hydroxyl, (CrC^alkoxy. carboxyl, CONH2.
-S(O)m(CrC6)alkyl, -CO2(C1-C4)alkyl ester, 1H-tetrazol-5-yl or 1 to 3 fluoro;
Y is O; R2 is hydrogen, -(C0-C3)alkyl-(C3-C8)cycloalkyl, phenyl or (CVCgJalkyl where
the (d-Cgialkyl group is optionally substituted with hydroxyl, -CF3 or 1 to 3 halogen.
A group of compounds, which is preferred among the "D Group" of
compounds, designated the "E Group", contains those compounds of the "D Group"
wherein w is 0 and n is 1.
Another group of compounds, which is preferred among the "D Group" of
compounds, designated the T Groupare those compounds of the "D Group",
having the formula I as shown hereinabove, wherein e is 0; n and w are each 1;
R1 is -(CH2),-A1;
where A1 in the definition of R1 is phenyl, thienyl, thiazolyl, pyridyl or pyrimidyl
which is optionally substituted with one to three substituents, each substituent
being independently selected from the group consisting of F, Cl, Me, OMe,
CF3, OCF3 and OCF2H;
t is 0,1 or 2;
and R3 is phenyl-CH2-O-CH2-, phenyl-(CH2)3- or 3-indolyl-CH2-, where the aryl
portion is optionally substituted with one to three substituents, each substituent being
independently selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 or
OCF2H.
A group of compounds, which is preferred among the "F Group" of
compounds, designated the "G Group", contains those compounds of the "F Group",
having the formula I as shown hereinabove, wherein X5 and X5a are each methyl; R1
is -CH2-phenyl, -CH2-4-fluoro-phenyl, -CH2-pyridyl or -CH2-thiazolyl and R2 is
hydrogen, methyl, ethyl, t-butyl or -CH2CF3.
A group of compounds, which is preferred among the "G Group" of
compounds, designated the "G1 Group", contains those compounds of the "G
Group*, and have the formula
the racemic-diastereomeric mixtures and optical isomers of said compounds wherein
R1 is -CH2-phenyl, R2 is methyl and R3 is -(CH2)3-phenyl;
R1 is -CH2-phenyl, R2 is methyl and R3 is 3-indolyl-CH2-;
R1 is -CH2-phenyl, R2 is ethyl and R3 is 3-indolyl-CH2-;
R1 is -CH2-4-fluoro-phenyl, R2 is methyl and R3 is 3-indolyl-CH2-;
R1 is -CH2-phenyl, R2 is methyl and R3 is -CH2-O-CH2-phenyl;
R1 is -CHjrphenyl, R2 is ethyl and R3 is -CH2-O-CH2-phenyl;
R1 is -CHrphenyl, R2 is -CH2-CF3 and R3 is -CH2-O-CH2-phenyl;
R1 is -CH2-4-fluoro-phenyl, R2 is methyl and R3 is -CH2-O-CH2-phenyl;
R1 is -CH2-phenyl, R2 is t-butyl and R3 is -CH2-O-CH2-phenyl; or
R1 is -CH2-phenyl, R2 is methyl and R3 is -CH2-O-CH2-3,4-di-fluoro-phenyl.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R,S)-benzyl-2-methyl-3-
oxo-2,3,3a,4,6l7-hexahydro-pyrazolo[4l3-c]pyridin-5-yl)-1-(R)-(3,4-difluoro-benzyloxymethyl)-
2-oxo-ethyl]-2-methyl-propionamide is preferred among the "G1 Group" of
compounds and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
A group of compounds, which is preferred among the "G Group" of
compounds, designated the "H Group", contains those compounds of the "G Group",
having the formula I as shown hereinabove, wherein R1 is -CH2-phenyl and R3 is
phenyl-(CH2)3-.
The diastereomeric mixture of 2-amino-N-[1-(3a-(R,S)-benzyl-2-methyl-3-
oxo-2,3, 3a ,4,6,7-hexahydro-pyrazolo[4,3-c]pyridine-5-carbonyl)-4-phenyl-(R)-buty
isobutyramide is preferred among the "H Group" of compounds and the separated
A group of compounds, which is preferred among the "G Group" of
compounds, designated the "I Group", contains those compounds of the "G Group"
wherein R1 is -CH2-phenyl or -CH2-4-fluoro-phenyl and R3 is 3-indolyl-CH2-.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R,S)-ben2yl-2-methyl-3-
oxo-2,3,3a,4l6,7-hexahydro-pyrazolo-[4,3-c]pyridin-5-yl)-1-(R)-(1H-indol-3-ylmethyl)-
2-oxo-ethyl]-isobutyramide is preferred among the "I Group" of compounds and the
separated 3a-(R) and 3a-(S) isomers are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-(2-(3a-(R,S)-benzyl-2-ethyl-3-oxo-
2,3,3a,4,6,7-hexahydro-pyra20lo[4,3-c]pyridin-5-yl)-1-(R)-(1H-indol-3-ylmethyl)-2-
oxo-ethyl]-isobutyramide is also preferred among the "I Group" of compounds and
the separated 3a-(R) and 3a-(S) isomers are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-[2-[3a-(R,S)-(4-fluoro-ben2yl)-2-
methyl-S-oxo^.S.Sa^.e.T-hexahydro-pyrazoloK.S-cJpyridin-S-ylJ-I^RJ^IH-indol-Sylmethyl)-
2-oxo-ethyl]-isobutyramide is also preferred among the "I Group" of
compounds and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
A group of compounds which is preferred among the "G Group" of
compounds, designated the "J Group", contains those compounds of the "G Group"
wherein R1 is -CH2-phenyl or -CH2-4-fluoro-phenyl and R3 is phenyl-CH2-O-CH2-.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R,S)-benzyl-2-methyl-3-
oxo-2,3,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-
oxo-ethyl]-isobutyramide is preferred among the "J Group" of compounds, the
separated 3a-(R) and 3a-(S) isomers are preferred of the diastereomeric mixture, the
3a-(R) isomer is preferred over the 3a-(S) isomer, and the L-tartaric acid salt of the
3a-(R) isomer is a preferred salt.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R,S)-benzyl-2-ethyl-3-oxo-
2,3, 3a ,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-1 -(R)-benzyloxymethy l-2-oxoethyl]-
isobutyramide is also preferred among the "J Group" of compounds and the
separated 3a-(R) and 3a-(S) isomers are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-{2-[3a-(R,S)-benzyl-3-oxo-2-(2,2,2-
tnfluoro-ethyl)-2,3,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl]-1-(R)-
benzyloxymethyl-2-oxo-ethyl}-isobutyramide is also preferred among the "J Group"
of compounds, the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture and the 3a-(R) isomer is preferred over the 3a-(S) isomer.
The diastereomeric mixture of 2-amino-N-{1-(R)-benzyloxymethyl-2-{3a-
(R,S)-(4-fluoro-benzyl)-2-methyl-3-oxo-2,3,3a,41617-hexahydro-pyra2olo[413-
c]pyridin-5-yl]-2-oxo-ethyl)-isobutyramide is also preferred among the "J Group* of
compounds and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R.S)-benzyl-2-tert-butyl-3-
oxo-2,3,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-1 -(R)-benzyloxymethyl-2-
oxo-ethyl]-isobutyramide is also preferred among the "J Group" of compounds and
the separated 3a-(R) and 3a-(S) isomers are preferred of the diastereomeric mixture.
A group of compounds which is preferred among the "D Group" of
compounds, designated the "K Group", contains those compounds of the "D Group"
wherein e is 1; n is 1; w is 1; R1 is -(CH2)t-A1;
where A1 in the definition of R1 is phenyl, thienyl, thiazolyl, pyridyl or pyrimidyl
which is optionally substituted with one to three substituents, each substituent
being independently selected from the group consisting of F, Cl, Me, OMe,

nd R3 is phenyl-CH2-O-CH2-, phenyl-(CH2)3- or 3-indolyl-CH2-, where the aryl
portion is optionally substituted with one to three substituents, each substituent being
independently selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 or
A group of compounds which is preferred among the "K Group" of
compounds, designated the "L Group", are those compounds of the "K Group"
wherein X5 and Xsare each methyl; R1 is -CH2-phenyl, -CH2-4-fluoro-phenyl, -CH2-
pyridyl or -CH2-thiazolyl and R2 is hydrogen, methyl, ethyl, t-butyl or -CH2CF3.
A group of compounds which is preferred among the "L Group", designated
the "L1 Group", are those compounds of the "L Group" wherein R1 is -CH2-phenyl; R2
is hydrogen or methyl and R3 is -CH2-O-CH2-phenyl.
The diastereomeric mixture of 2-amino-N-[2-(3a-(R,S)-benzyl-3-oxo-
2,3,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2- isobutyramide is preferred among the "J Group", the separated 3a-(R) and 3a-
(S) isomers are preferred of the diastereomeric mixture and the 3a-(R) isomer is
preferred over the 3a-(S) fsomer.
Another group of compounds, which is preferred among the "A Group" of
compounds, designated the "M Group", contains those compounds of the "A Group",
having the formula I as shown hereinabove, wherein b is 0; X5 and X5a are each
independently hydrogen, (CfCsJalkyl or hydroxy(CrC3)alkyl;
R3 is selected from the group consisting of 1-indolyl-CH2-, 2-indolyl-CH2-, 3-indolyl-
CH2-, 1-naphthyl-CH2-, 2-naphthyl-CH2-, 1-ben2imidazolyl-CH2-, 2-benzimidazolyl-
CH2-, phenyl-fCt-Calkyl-, 2-pyridyl-(C1-C4)alkyl-, 3-pyridyl-(CrC4)alkyl-, 4-pyridyl-
(d-Calkyl-. phenyl-CH2-S-CH2-, thienyKd-Calkyl-, phenyKC0-C3)alkyl-O-CHr,
phenyl-CH2-O-phenyl-CH2-, 3-benzothienyl-CH2-, thienyl-CH2-O-CH2-, thiazolyl-
CH2-O-CH2-, pyridyl-CH2-O-CH2-, pyrimidyl-CH2-O-CH2- and phenyl-O-CH2-CH2;
where the aryl portion(s) of the groups defined for R3 are optionally
substituted with one to three substituents, each substituent being
independently selected from the group consisting of methylenedioxy, F, Cl,
CH3, OCH3, OCF3, OCF2H and CF3.
A group of compounds, which is preferred among the "M Group" of
compounds, designated the "M1 Group", contains those compounds of the "M
Group", having the formula I as shown hereinabove, wherein R4 is hydrogen; a is 0;
n is 1; w is 1; e is 0; X5 and X5a are each independently, hydrogen, methyl or
hydroxymethyl, provided that when X5 is hydrogen then X5 is not hydrogen; R7 and
R8 are each hydrogen; Y is oxygen; R2 is hydrogen, methyl, ethyl, propyl, i-propyl,
-CH2CF3l GF3 or -CH2-cyclopropyl; R1 is CH2-A1; where A1 in the definition of
R1 is phenyl, thienyl, thiazolyl, pyridyl or pyrimidyl which is optionally substituted with
one to three substituents, each substituent being independently selected from the
group consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H; and R3 is phenyl-CH2-
O-CH2-, phenyl-(CH2)r, 3-indolyl-CH2-, thienyl-CH2-O-CH2-, thiazolyl-CH2-O-CH2- ,
pyridyl-CH2-O-CH2- , pyrimidyl-CH2-O-CH2- or phenyl-O-CH2-CH2, where the aryl
portion is optionally substituted with one to three substituents, each substituent being
independently selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 and
A group of compounds, which is preferred among the "M1 Group" of
compounds, designated the "N Group", contains those compounds of the "M1
Group", having the formula I as shown hereinabove, wherein Xs and X5" are each
methyl; R2 is methyl, ethyl, or -CH2CF3; A1 is phenyl optionally substituted with one
to three substituents, each substituent being independently selected from the group
consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H; R3 is phenyl-CH2-O-CH2-,
phenyl-(CH2)3- or thienyl-CH2-O-CH2- where the aryl portion is optionally substituted
with one to three substituents, each substituent being independently selected from
the group consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H.
Another group of compounds, which is preferred among the *M1 Group* of
compounds, designated the "O Group", contains those compounds of the "M1
Group", having the formula I as shown hereinabove, wherein Xs and X5* are each
methyl; R2 is methyl, ethyl, or CH2CF3; A1 is 2-pyridyl or 3-pyridyl optionally
substituted with one to two substituents, each substituent being independently
selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H; R3 is
phenyl-CH2-O-CH2-, phenyl-(CH2)3- or thienyl-CH2-O-CH2- where the aryl portion is
optionally substituted with one to three substituents, each substituent being
independently selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 and
Another group of compounds, which is preferred among the "M1 Group" of
compounds, designated the "P Group", contains those compounds of the "M1
Group", having the formula I as shown hereinabove, wherein X5 and X5" are each
methyl; R2 is methyl, ethyl, or CH2CF3; A1 is phenyl optionally substituted with one to
three substituents, each substituent being independently selected from the group
consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H; R3 is 2-pyridyl-CH2-O-CH2-, °r
3-pyridyl-CH2-O-CH2- where the aryl portion is optionally substituted with one to two
substituents, each substituent being independently selected from the group
consisting of F, Cl, Me, OMe, CF3, OCF3 and OCF2H.
A group of compounds, which is preferred among the "O Group" of
compounds, designated the "Q Group", contains those compounds of the "O Group",
the racemic-diastereomeric mixtures and optical isomers of said compounds wherein
R2 is methyl; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-phenyl;
R2 is CH2CF3; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-3-chloro-phenyl;
R2 is CH2CF3; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-4-chloro-phenyl;
R2 is CH2CF3; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-2,4-di-chloro-phenyl;
R2 is CH2CF3; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-3-chloro-thiophene; or
R2 is CH2CF3; A1 is 2-pyridyl; and R3 is -CH2-O-CH2-2,4-di-fluoro-phenyl.
The diastereomeric mixture of 2-amino-N-[1-(R)-benzyloxymethyl-2-(2-
methyl-3-oxo-3a-(R,S)-pyridin-2-ylmethyl-2,313a,4,6,7-hexahydro-pyra2olo[4,3-
c]pyridin-5-yl)-2-oxo-ethyl]-2-methyl-propionamide is preferred among the "Q Group"
of compounds and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-{1-(R)-(3-chloro-benzyloxy-methyl)-
2-oxo-2-[S-oxo-Sa-tR.SJ-pyridin^-ylmethyl^^^^-trifluoro-ethyO^.S.Sa^.e,?-
hexahydro-pyrazolo[4,3-c]pyridin-5-yl]-ethyl}-2-methyl-propionamide is preferred
among the "Q Group' of compounds and the separated 3a-(R) and 3a-(S) isomers
are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-{1-(R)-(4-chloro-ben2yloxy-methyl)-
2-oxo-2-{3-oxo-3a-(R1S)-pyridin-2-ylmethyl-2-(2,2I2-trifluoro-ethyl)-2,3,3a,4,6,7-
hexahydro-pyrazolo[4,3-c ]pyridin-5-yl]-ethyl}-2-methyl-propionamide is preferred
among the "Q Group' of compounds and the separated 3a-(R) and 3a-(S) isomers
are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-{1-(R)-(2,4-dichlorobenzyloxymethyl)-
2-oxo-2-[3-oxo-3a-(R,S)-pyridin-2-ylmethyl-2-(2,2,2-trifluoro-ethyl)-
213,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl]-ethyl}-2-methyl-propionamide is
preferred among the "Q Group" of compounds and the separated 3a-(R) and 3a-(S)
isomers are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-amino-N-{1-(R)-(4-chloro-thiophen-2-
ylmethoxymethyl)-2-oxo-2-[3-oxo-3a-(R,S)-pyridin-2-ylmethyl-2-(2,2,2-trifluoro-ethyl)-
2,3,3a,4,5,7-hexahydro-pyrazolo[3,4-c]pyridin-6-yl]-ethyl}-2-methyl-propionamide is
preferred among the Group" of compounds and the separated 3a-(R) and 3a-(S)
isomers are preferred of the diastereomeric mixture.
The diastereomeric mixture of 2-am]no-N-{1-(R)-(2,4-difluoro-ben2yloxymethyl)-
2-oxo-2-[3-oxo-3a-(R,S)-pyridin-2-ylmethyl-2-(2,2,2-trifluoro-ethyl)-
2,3,3a,4,6,7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl]-ethyl}-2-methyl-propionamide is
preferred among the "Q Group" of compounds and the separated 3a-(R) and 3a-(S)
isomers are preferred of the diastereomeric mixture.
A group of compounds which contains intermediates useful in synthesizing
the compounds of formula (I) are of the formula
(Figure Removed) the racemic-diastereomeric mixtures and optical isomers of said compounds and the
pharmaceutically-acceptable salts thereof, wherein e is 0 or 1; n and w are each
where the alkyl and cycloalkyl groups in the definition of R1 are optionally
substituted with (CrC4)alkyl, hydroxyl, (C1-C4)alkoxy, carboxyl, CONH2,
-S(O)m(C1-C6)alkyl, -CO2(C1-C4)alkyl, 1 H-tetrazol-5-yl or 1 to 3 fluoro; Y1 is O,
S(O)m, -C(0)NX6, -CH=CH-, -CsC-, -N(X6)C(O)-) -C(O)NX6-, -C(O)O-,
-OC(O)N(X6)- or -OC(O)-; q is 0, 1 , 2, 3 or 4; t is 0, 1 , 2 or 3;
said (CH2)q group and (CH2), group may each be optionally substituted with 1
to 3 fluoro, 1 or 2 (CrC4)alkyl, hydroxyl, (CrC4)alkoxy, carboxyl, -CONH2,
-S(O)m(CrC6)alkyl, -CO2(CrC4)a\W ester, or 1 H-tetrazol-5-yl;
R2 is hydrogen, (d-CsJalkyl, -(Co-C3)alkyl-(C3-Ce)cycloalkyl, -(C1-C4)alkyl-A1 or A1;
where the alkyl groups and the cycloalkyl groups in the definition of R2 are optionally
substituted by hydroxyl, -C(O)OX6, -C(O)N(X6)(X6), -N(X6)(X8),
-S(O)m(CrC6)alkyl, -C(O)A1, -CfOXX6), CF3, ON or 1 to 3 halogen;
A1 for each occurrence is independently (C5-C7)cycloalkenyl, phenyl or a partially
saturated, fully saturated or fully unsaturated 4- to 8-membered ring optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
oxygen, sulfur and nitrogen, or a bicyclic ring system consisting of a partially
saturated, fully unsaturated or fully saturated 5- or 6-membered ring, optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
nitrogen, sulfur and oxygen, fused to a partially saturated, fully saturated or fully
unsaturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or
optionally both rings if A1 is a bicyclic ring system, with up to three
substituents, each substituent independently selected from the group
consisting of F, Cl, Br, I, OCF3, OCF2H, CF3, CH3, OCH3, -OX6,
-C(O)N(X8)(X6), -C(O)OX6, oxo, (d-CeJalkyl, nitro. cyano, benzyl,
-S(O)m(CrC6)alkyl, 1 H-tetrazol-5-yl, phenyl, phenoxy, phenylalkyloxy,
halophenyl, methylenedioxy, -N(X6)(X6), -N(X6)C(O)(X6), -SO2N(X6)(X6),
-N(X6)S02-phenyl, -N(X6)SO2X6, -CONX11X12, -SO2NX11X12, -NX6SO2X12,
-NX6CONX11X12, -NX6SO2NX11X12, -NX6C(O)X12, imidazolyl, thiazolyl and
tetrazolyl, provided that if A1 is optionally substituted with methylenedioxy
then it can only be substituted by one methylenedioxy;
where X11 is hydrogen or optionally substituted (CrC6)alkyl;
the optionally substituted (CrC6)alkyl defined for X11 is
optionally independently substituted with phenyl, phenoxy, (Cr
C6)alkoxycarbonyl, -S(O)m(C1-C6)alkyl, 1 to 5 halogens. 1 to 3
hydroxy, 1 to 3 (CCalkanoyloxy or 1 to 3 (CrC6)alkoxy;
X12 is hydrogen, (CrC6)alkyl, phenyl, thiazolyl, imidazolyl, furyl or
thienyl, provided that when X12 is not hydrogen, X12 is optionally
substituted with one to three substituents independently selected from
the group consisting of Cl, F, CH3, OCH3. OCF3 and CF3;
or X11 and X12 are taken together to form -{CH^rL'-fCHsJr;
L1 is C(X2)(X2), O, S(0)m or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted (Cr
C8)alkyl, or optionally substituted (C3-C7)cycloalkyl, where the optionally substituted
(CrC6)alkyl and optionally substituted (C3-C7)cycloalkyl in the definition of X2 are
optionally independently substituted with -S(O)m(CrC6)alkyl. -C(O)OX3, 1 to 5
halogens or 1 to 3 OX3;
X3 for each occurrence is independently hydrogen or (d-C6)alkyl;
X6 for each occurrence is independently hydrogen, optionally substituted (Cr
C6)alkyl, (C2-C6)halogenated alky I, optionally substituted (C3-C7)cycloalkyl, (C3-C7)-
halogenatedcycloalkyl, where optionally substituted (C1-Ce)alkyl and optionally
substituted (C3-C7)cycloafkyl in the definition of X6 is optionally independently
substituted by, hydroxyl, (CrC4)alkoxy, carboxyl, CONH2, -S(O)m(C1-C6)alkyl,
-COztCt-C.OalkyI, 1H-tetrazol-5-yl or 1 or 2 (d-C^alkyl; or
where there are two X6 groups on one atom and both Xs are (C1-Ce)alkyl. the two
(CrC6)alkyl groups may be optionally joined and, together with the atom to which the
two X6 groups are attached, form a 4- to 9- membered ring optionally having oxygen,
sulfur or NX7;
X7 is hydrogen or (CrCs)alkyl optionally substituted with hydroxyl; and
m for each occurrence is independently 0, 1 or 2;
with the proviso that:
X6 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form
C(O)X6, C(O)X12, SO2X6 or SO2X12; and
when R2 is hydrogen then R1 is not -CH=CH-phenyl.
A group of intermediate compounds preferred among the foregoing group of
formula (il), designated "Group AA", contains those compounds wherein w is 0 or 1;
n is 1; R1 is hydrogen, -(CH2)q-(C3-C7)cycloalkyl, -(CH2),-A1 or (CrC10)aikyl where
the (CrC10)alkyl and (C3-C7)cycloalkyl groups are optionally substituted with 1 to 3
fluoro and A1 in the definition of R1 is optionally substituted with 1 to 3 substituents
independently selected from the group consisting of F, Cl, Me, methoxy, CF3, OCF3
and OCF2H; R2 is hydrogen, (d-CgJalkyl, (Co-C3)alkyl-(C3-C7)cycloalkyl, phenyl, or
(CrC3)alkyl-phenyl where the alkyl and phenyl groups are optionally substituted with
1 to 3 substituents independently selected from the group consisting of F, CF3. OH
and methoxy.
A group of compounds preferred among the "AA Group" compounds,
designated "BB Group", contains those compounds of "AA Group" wherein w is 1; e
is 0; R1 is -CH2-pyridyl, -CH2-thiazolyl, or -CH2-phenyl optionally substituted with 1 to
3 substituents independently selected from the group consisting of fluoro and chloro;
and R2 is hydrogen, (CrC4)alkyl or phenyl where the (C1-C4)alkyl or phenyl groups in
the definition of R2 is optionally substituted with 1 to 3 substituents independently
selected from the group consisting of fluoro, hydroxy or methoxy.
Compounds which are preferred among the "BB Group" compounds is the
diastereomeric mixture of a compound wherein R1 is -CH2-phenyl and R2 is methyl or
hydrogen; and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
Another group of intermediate compounds which are useful in the synthesis
of the compounds of formula (I) have the formula
the racemic-diastereomeric mixtures and optical isomers of said compounds wherein
Z100 is methyl, BOC, CBZ, CF3C(O)-, FMOC, TROC, trityl, tosyl, CH3C(O)- or
optionally substituted benzyl which optionally substituted with methoxy, dimethoxy or
nitro; e is 0 or 1; n and w are each independently 0, 1 or 2, provided that w and n
cannot both be 0 at the same time;
R1 is hydrogen, -CN, -(CH2)qN(X6)C(O)X6, -(CH2)qN(X6)C(O)(CH2),-A1,
-(CH2)qN(X6)S02(CH2)rA1,-(CH2)qN(X6)S02X6, -(CH2)qN(X6)C(O)N(X6)(CH2)t-A1,
-(CH2)qN(X6)C(0)N(X6)(X6),-(CH2)qC(0)N(X6)(X6),-(CH2)qC(0)N(X6)(CH2)t-A1,
-(CH2)qC(0)OX6, -(CH2)qC(0)0(CH2)t-A1, -(CH2)qOX6, -(CH2)qOC(O)X6,
-(CH2)qOC(0)(CH2)t-A1
l-(CH2)qOC(0)N(X6)(CH2)rA1,-(CH2)qOC(0)N(Xa)(Xa),
-(CH2)qC(0)X6. -(CH2)qC(0)(CH2)t-A1, -(CH2)qN(X6)C(O)OX,
-(CH2)qN(X6)S02N(X6)(X6). -(CHzJqSCOJJC6, -(CH2)qS(O)m(CH2)t-A1,
-(CrC10)alkyl, -(CH2),-A1, -(CH2)q-(C3-C7)cycloalkyl. -(CH2)q-Y1-(C1-Ce)alkyl,
-(CH2)q-Y1-(CH2),-A1 or -(CH2)q-Y1-(CH2),-(C3-C7)cycloalkyl;
where the alkyl and cycloalkyl groups in the definition of R1 are optionally
substituted with (CrC.Oalkyl, hydroxyl, (C1-C4)alkoxy, carboxyl, CONH2l
-S(O)m(CrC6)alkyl, -CO2(C1-C4)alkyl, 1H-tetrazol-5-yl or 1 to 3 ftuoro;
Y1 is O, S(0)m> -C(0)NX6, -CH=CH-, -C=C-, -N(X8)C(O), -C(O)NX6,
-C(O)0, -OC(O)N(X6) or -OC(O);
said (CH2)q group and (CH2)t group may each be optionally substituted with
hydroxyl, (CrC4)alkoxy, carboxyl, -CONH2l -S(O)m(C1-C6)allcyl,
-CO2(CrC4)alkyl, IH-tetrazol-5-yl, 1 to 3 fluoro or 1 or 2 (C1-C4)alkyl;
R2 is hydrogen, (CrC8)alkyl, -(C0-C3)alkyl-(C3-C8)cycloalkyl, -(C1-C4)alkyl-A1 or A1;
where the alkyl groups and the cycloalkyl groups in the definition of R2 are optionally
substituted with hydroxyl, -C(O)OX6, -C(O)N(X6)(X6), -NfX6)^8),
-S(O)m(CrC6)alkyl, -C(O)A1, -C(O)(X6), CF3, CN or 1 to 3 halogen;
A1 for each occurrence is independently (Cs-C7)cycloalkenyl, phenyl or a partially
saturated, fully saturated or fully unsaturated 4- to 8-membered ring optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
oxygen, sulfur and nitrogen, or a bicyclic ring system consisting of a partially
saturated, fully unsaturated or fully saturated 5- or 6-membered ring, optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
nitrogen, sulfur and oxygen, fused to a partially saturated, fully saturated or fully
unsaturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or
optionally both rings if A1 is a bicyclic ring system, with up to three
substituents, each substituent independently selected from the group
consisting of F, Cl, Br, I, OCF3, OCF2H, CF3, CH3, OCH3, -OX6,
-C(O)N(X6)(X6), -C(O)OX6, oxo, (C1-C6)alkyl, nitro, cyano, benzyl,
-S(O)m(Ci-C«)alkyl, 1 H-tetrazol-5-yl, phenyl. phenoxy, phenylalkytoxy,
halophenyl, methylenedioxy, -N(X6)(X6), -N^CtOXX6), -SO2N(X8)(X6),
-N(X6)SO2-phenyl, -NfX^SOjX6, -CONX11X12, -SO2NX11X12, -NX*SO2X12,
-NX'CONX'V2, -NX6SO2NX11X12, -NX6C(O)X12, imidazoiyl, thiazolyl and
tetrazolyl, provided that if A1 is optionally substituted with methylenedioxy
then it can only be substituted with one methylenedioxy;
where X11 is hydrogen or optionally substituted (CrC6)alkyl;
the optionally substituted (d-C6)alkyl defined for X11 is
optionally independently substituted with phenyl, phenoxy, (Cr
C6)alkoxycarbonyl, -StOJm^-CeJalkyl, 1 to 5 halogens, 1 to 3
hydroxy, 1 to 3 (CrC10)alkanoyloxy or 1 to 3 (CrCa)alkoxy;
X12 is hydrogen, (d-CeJalkyl, phenyl, thiazolyl, imidazoiyl, furyl or
thienyl, provided that when X12 is not hydrogen, X12 is optionally
substituted with one to three substituents independently selected from
the group consisting of Cl, F, CH3, OCH3, OCF3 and CF3;
or X11 and X12 are taken together to form -(CH2)r-L1-(CH2)r;
L1 is C(X2)(X2), O, S(0)m or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted (Cr
C6)alkyl, or optionally substituted (C3-C7)cycloalkyl, where the optionally substituted
(CrC6)alkyl and optionally substituted (C3-C7)cycloalkyl in the definition of X2 are
optionally independently substituted with -S(O)m(C1-C«)alkyl, -C(O)OX3, 1 to 5
halogens or 1 to 3 OX3;
X3 for each occurrence is independently hydrogen or (CrC6)alkyl;
X6 for each occurrence is independently hydrogen, optionally substituted (Cv
C6)alkyl, (C2-C6)halogenated alkyl, optionally substituted (C3-C7)cycloalkyi, (C3-C7)-
halogenatedcycloaikyl, where optionally substituted (CrC6)alkyl and optionally
substituted (C3-C7)cycloalkyl in the definition of X6 is optionally independently
substituted with hydroxyl, (CrC4)alkoxy, carboxyl, CONH2l -S(O)m(CrC6)alkyl,
-CO2(C,-C4)alkyl, 1 H-tetrazol-5-yl or 1 or 2 (d-C^alkyl; or
where there are two X6 groups on one atom and both X6 are (CrC6)alkyl, the two
(CrC6)alkyl groups may be optionally joined and, together with the atom to which the
two X6 groups are attached, form a 4- to 9- membered ring optionally having oxygen,
sulfur or NX7;
X7 is hydrogen or (CVCeJalkyl optionally substituted with hydroxyl; and
m for each occurrence is independently 0, 1 or 2;
with the proviso that:
X6 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form
C(O)X6 C(O)X12, SO2X6 or SO2X12;
when R2 is hydrogen then R1 is not -CH=CH-phenyl;
when R2 is H and R1 is -CH2-CH=CH-Ph, then Z100 is not BOC;
when R2 is H and R1 is 2-cyclohexen-l-yl then ZIQO is not BOC
when R2 is H and R1 is -CH2-C(CH3)=CH2l then Z100 is not BOC; and
when R2 is phenyl and R1 is -CH3, then Z100 is not CH3qO)-
A group of compounds preferred among the foregoing group of compounds
of formula (III), designated "CC Group", are those compounds wherein w is 0 or Kn
Z100 is BOC, methyl, benzyl or CBZ;
R1 is hydrogen, -(CH2)q-(C3-C7)cycloalkyl, -(CH2)rA1 or (C^oJalkyl where the (Cr
C10)alkyl and (C3-C7)cycloalkyl groups are optionally substituted with 1 to 3 fluoro
and A1 in the definition of R1 is optionally substituted with 1 to 3 substituents
independently selected from the group consisting of F, Cl, Me, OMe, CF3, OCF3 and
R2 is hydrogen, (CrC8)alkyl, -(C0-C3)alkyl-(C3-C7)cycloalkyl, phenyl, or -(CrC3)alkylphenyl
where the alkyl and phenyl groups are optionally substituted with 1 to 3
substituents independently selected from the group consisting of F, CF3, OH and
A group of compounds preferred among the "CC Group" compounds,
designated "DD Group", contains those compounds of "CC Group" wherein Z100 is
BOC; w is 1; e is 0; R1 is -CH2-pyridyl, -CH2-thiazolyl, or -CH2-phenyl optionally
substituted with 1 to 3 substituents independently selected from the group consisting
of fluoro and chloro; and R2 is hydrogen, (C^C^alkyl or phenyl where the (Cr
C4)alkyl or phenyl groups in the definition of R2 is optionally substituted with 1 to 3
substituents independently selected from the group consisting of fluoro, hydroxy and
methoxy.
Compounds which are preferred among the "DD Group" compounds is the
diastereomeric mixture of a compound wherein R1 is -CH2-phenyl and R2 is methyl or
hydrogen; and the separated 3a-(R) and 3a-(S) isomers are preferred of the
diastereomeric mixture.
Yet another group of compounds which are useful in the synthesis of the
compounds of formula (I) contains those compounds of the formula
the racemic-diastereomeric mixtures and optical isomers of said compounds wherein
Z200 is t-BOC, CBZ, CF3C(O)-, FMOC, TROC, trityl, tosyl or optionally substituted
benzyl which is optionally substituted with methoxy, dimethoxy or nitro;
e is 0 or 1;
n and w are each independently 0, 1 or 2, provided that w and n cannot both be 0 at
the same time;
Y is oxygen or sulfur;
R1 is hydrogen, -CN, -(CH2)qN(X6)C(O)X8. -(CH2)qN(X6)C(O)(CH2)rA1,
-(CH2)qN(X6)S02(CH2)rA1
l-(CH2)qN(X6)S02X6,-(CH2)qN(X6)C(0)N(Xfl)(CH2)rA1,
-(CH2)qN(X6)C(0)N(X6)(X6),-(CH2)qC(0)N(X6)(X6),-(CH2)qC(0)N(X6)(CH2)rA1,
-(CH2)qC(0)OX6, -(CH2)qC(0)0(CH2)t-A1, -(CH^OX6, -(CH2)qOC(O)X6,
-(CH2)qOC(0)(CH2)rA1,-(CH2)qOC(0)N(X6)(CH2)rA1,-(CH2)qOC(0)N(X6)(X6)>
-(CH2)qC(0)X6, -(CH2)qC(0)(CH2)t-A1, -(CH2)qN(X6)C(O)OX6,
-(CH2)qN(X6)S02N(X6)(X6), -(CH2)qS(0)mX6, -(CH2)qS(O)m(CH2),-A1,
-(CrC10)alkyl, -(CH2),-A1, -(CH2)q-(C3-C7)cycloalkyl, -(CH2)q-Y1-(C1-C6)alkyl,
-(CH2)q-Y1-(CH2)rA1 or -(CH2)q-Y1-(CH2),-(C3-C7)cycloalkyl;
where the alkyl and cycloalkyl groups in the definition of R1 are optionally
substituted with (CVCalkyl, hydroxyl, (CVCalkoxy, carboxyl, CONH2l
-S(O)m(CrC6)alkyl. -CO2(CrC4)alkyl ester, 1 H-tetrazol-5-yl or 1 to 3 fluoro;
Y1 is O, S(O)m, -CfONX6, -CH=CH-, -C^C-, -N(X6)C(O), -C(O)NX6,
-C(O)O, ~OC(O)U(X?) or -OC(O);
q isO, 1, 2, 3 or 4;
t is 0, 1, 2 or 3;
said (CH2)q group and (CH2), group may each be optionally substituted with
hydroxyl, (d-C4)alkoxy, carboxyl, -CONH2, -S(O)m(C1-C6)alkyl,
-CO2(d-d)alkyl, 1H-tetrazol-5-yl, 1 to 3 fluoro or 1 or 2 (d-C4)alkyl;
R2 is hydrogen, (d-C8)alkyl, -(Co-CaJalkyHCa-CaJcydoalkyl, -(d-C^alkyl-A1 or A1;
where the alky) groups and the cycloalkyl groups in the definition of R2 are optionally
substituted with hydroxyl, -C(O)OX6, -C(O)N(X6)(X6), -N(X6)(X6), -S(O)m(CrC6)alkyl,
-C(O)A', -CfOXX6), CF3, CN or 1 to 3 halogen;
R3 is A1, (d-do)alkyl, -(d-Ce)alkyl-A1, -(d-C6)alkyl-(C3-C7)cycloalkyl,
-(d-C5)alkyl-X1-(d-C5)alkyl, -(d-C5)alkyl-X1-(C0-C5)alkyl-A1 or
-(C1-C5)alkyl-X1-(d-C5)alkyl-(C3-d)cycloalkyl;
where the alkyl groups in the definition of R3 is optionally substituted with
-S(O)m(d-C6)alkyl, -C(O)OX3, 1 to 5 halogens or 1 to 3 OX3;
X1 is O, S(O)m, -N(X2)C(O)-, -C(O)N(X2)-, -OC(O)-, -C(O)O-, -CX2=CX2-,
-N(X2)C(O)O-, -OC(O)N(X2)- or -C=C-;
R4 is hydrogen, (d-C6)alkyl or (C3-C7)cycloalkyl, or R4 is taken together with R3 and
the carbon atom to which they are attached and form (C5-C7)cycloalkyl, (C5-
C7)cycloalkenyl, a partially saturated or fully saturated 4- to 8-membered ring having
1 to 4 heteroatoms independently selected from the group consisting of oxygen,
sulfur and nitrogen, or is a bicydic ring system consisting of a partially saturated or
fully saturated 5- or 6-membered ring, fused to a partially saturated, fully unsaturated
or fully saturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
X4 is hydrogen or (d-C6)alkyl or X4 is taken together with R4 and the nitrogen atom
to which X4 is attached and the carbon atom to which R4 is attached and form a five
where a and b are independently 0, 1, 2 or 3;
X5 and X5" are each independently selected from the group consisting of
hydrogen, trifluoromethyl, A1 and optionally substituted (C1-C6)alkyl;
the optionally substituted (CrCeJalkyl in the definition of X5 and X5" is
optionally substituted with a substituent selected from the group
consisting of A1, -OX2, -S(O)m(CrCe)a\ky\, -C(O)OX2,
(C3-C7)cycloalkyl, -N(X2)(X2) and -C(O)N(X2)(X2);
or the carbon bearing X5 and X5 forms an alkylene bridge with the nitrogen
200 ft atom bearing Z and R where the alkylene bridge contains 1 to 5 carbon
atoms provided that X5 or X5" but not both may be on the carbon atom and
Z200 or R8 but not both may be on the nitrogen atom;
or X5 is taken together with X5 and the carbon atom to which they are
attached and form a partially saturated or fully saturated 3- to 7-membered
ring, or a partially saturated or fully saturated 4- to 8-membered ring having 1
to 4 heteroatoms independently selected from the group consisting of
oxygen, sulfur and nitrogen;
or X5 is taken together with X59 and the carbon atom to which they are
attached and form a bicyclic ring system consisting of a partially saturated or
fully saturated 5- or 6-membered ring, optionally having 1 or 2 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and
oxygen, fused to a partially saturated, fully saturated or fully unsaturated 5- or
6-membered ring, optionally having 1 to 4 heteroatoms independently
selected from the group consisting of nitrogen, sulfur and oxygen;
Z1 is a bond, O or N-X2, provided that when a and b are both 0 then Z1 is not
N-X2 or O;
R8 is hydrogen or optionally substituted (CrC6)alkyl;
where the optionally substituted (C^CeJalkyl in the definition of R8 is
optionally independently substituted with A1, -C(O)O-(CrC6)alkyl,
-S(O)m(C1-C6)alkyl, 1 to 5 halogens, 1 to 3 hydroxy, 1 to 3 -O-C(O)(C,-
C10)alkyl or 1 to 3 (CrC6)alkoxy; or
A1 for each occurrence is independently (C5-C7)cycloalkenyl, phenyl or a partially
saturated, fully saturated or fully unsaturated 4- to 8-membered ring optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
xygen, sulfur and nitrogen, or a bicyclic ring system consisting of a partially
saturated, fully unsaturated or fully saturated 5- or 6-membered ring, optionally
having 1 to 4 heteroatoms independently selected from the group consisting of
nitrogen, sulfur and oxygen, fused to a partially saturated, fully saturated or fully
unsaturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or
optionally both rings if A1 is a bicyclic ring system, with up to three
substituents. each substituent independently selected from the group
consisting of F, Cl, Br, I, OCF3, OCF2H, CF3, CH3, OCH3. -OX8,
-C(O)N(X6)(X6), -C(O)OX6, oxo, (CrCeJalkyl, nitro, cyano, benzyl,
-SfOJJCrCeJalkyl, 1 H-tetrazol-5-yl, phenyl, phenoxy, phenylalkyloxy,
halophenyl, methylenedioxy, -N(X6)(X8), -N(X6)C(O)(Xfl), -SO2U(X6)(X*),
-NfX^SCVphenyl, -N(X6)SO2X6, -CONX11X12, -SO2NX11X12, -NX6SO2X12,
-NX8CONX11X12, -NX6SO2NX11X12, -NX6C(O)X12, imidazolyl, thiazolyl and
tetrazolyl, provided that if A1 is optionally substituted with methylenedioxy
then it can only be substituted with one methylenedioxy;
where X11 is hydrogen or optionally substituted (CrC6)alkyl;
the optionally substituted (C,-C6)alkyl defined for X11 is
optionally independently substituted with phenyl, phenoxy, (Cr
C6)alkoxycarbonyl, -S(O)m(CrC6)alkyl, 1 to 5 halogens, 1 to 3
hydroxy, 1 to 3 (C1-C10)alkanoyloxy or 1 to 3 (CrC6)alkoxy;
X12 is hydrogen, (CrC6)alkyl, phenyl, thiazolyl, imidazolyl, fury! or
thienyl, provided that when X12 is not hydrogen, X12 is optionally
substituted with one to three substituents independently selected from
the group consisting of Cl, F, CH3, OCH3l OCF3 and CF3;
or X11 and X12 are taken together to form -(CH2)r-L1-(CH2)r-;
L1 is C(X2)(X2), O, S(0)m or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted (Cr
C6)alkyl, or optionally substituted (C3-C7)cycloalkyl, where the optionally substituted
(CrC6)alkyl and optionally substituted (C3-C7)cycloalkyl in the definition of X2 are
optionally independently substituted with -S(O)malkyl, -C(O)OX3, 1 to 5
halogens or 1 to 3 -OX3;
X3 for each occurrence is independently hydrogen or (C^CeJalkyl;
X6 for each occurrence is independently hydrogen, optionally substituted (Cr
C6)alkyl, (C2-C6)halogenated alkyl, optionally substituted (C3-C7)cycloalkyl, (C3-C7)-
halogenatedcycloalkyl, where optionally substituted (CrC6)a\ky\ and optionally
substituted (C3-C7)cycloalkyl in the definition of X0 is optionally independently
substituted with hydroxyl, (d-C4)alkoxy, carboxyl, CONH2, -S(O)ffl(C1-C6)alkyl,
-CO2(C,-C4)alkyl, 1 H-tetrazol-5-yl or 1 or 2 (d-C^alkyl; or
when there are two X6 groups on one atom and both X6 are (C1-C6)alkyl, the two (Cr
C6)alkyl groups may be optionally joined and, together with the atom to which the X6 groups are attached, form a 4- to 9- membered ring optionally having oxygen,
sulfur or NX7;
X7 is hydrogen or (CrC6)alkyl optionally substituted by hydroxyl; and
m for each occurrence is independently 0,1 or 2;
with the proviso that:
X6 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form
C(O)X6, C(O)X12, SO2X6 or SO2X12; and
when R6 is a bond then L is N(X2) and each r in the definition -(CH2)r-L-(CH2)r- is 2 or
Compounds which are preferred of the foregoing compounds of formula (IV)
is the compound wherein e is 0; Y is O; R1 is -CH2-phenyl; R2 is methyl or hydrogen;
n is 1; w is 1; R3 is -CH2-O-CH2-phenyl; R4 is hydrogen; X4 is hydrogen; R6 is
-C(CH3)2-; Z200 is BOG and R8 is hydrogen.
This invention also provides:
a method for increasing levels of endogenous growth hormone in a human or
other animal which comprises administering to such human or other animal an
effective amount of a compound of Formula I;
a pharmaceutical composition useful for increasing the endogenous
production or release of growth hormone in a human or other animal which
comprises an inert carrier and an effective amount of a compound of Formula I;
a pharmaceutical composition useful for increasing the endogenous
production or release of growth hormone in a human or other animal which
compnses an inert carrier, an effective amount of a compound of Formula I and
another growth hormone secretagogue such as. GHRP-6, Hexarelin, GHRP-1, IGF-
1, IGF-2, B-HT920 or growth hormone releasing factor (GRF) or an analog thereof;
a method for the treatment or prevention of osteoporosis which comprises
administering to a human or other animal in need of such treatment or prevention an
amount of a compound of Formula I which is effective in treating or preventing
osteoporosis;
a method for the treatment or prevention of osteoporosis which comprises
administering to a human or other animal with osteoporosis a combination of a
bisphosphonate compound such as alendronate, and especially preferred is the
bisphosphonate compound ibandronate, and a compound of Formula I;
a method for the treatment or prevention of osteoporosis which comprises
administering to a human or other animal with osteoporosis a combination of
estrogen or Premarin® and a compound of Formula I and optionally progesterone;
a method to increase IGF-1 levels in IGF-1 deficient humans or other animals
which comprises administering to a human or other animal with IGF-1 deficiency a
compound of Formula I;
a method for the treatment of osteoporosis which comprises administering to
a human or other animal with osteoporosis a combination of an estrogen agonist or
antagonist such as tamoxifen, droloxifene, raloxifene and idoxifene and a compound
of Formula I;
a particularly preferred method for the treatment of osteoporosis comprises
administering to a human or other animal with osteoporosis a combination of an
estrogen agonist or antagonist such as C/s-6-(4-fluoro-phenyl)-5-[4-(2-piperidin-1-ylethoxy)-
phenyl]-5,6,7,8-tetrahydro-naphthalene-2-ol;
(-)-c/s-6-phenyl-5-[4-{2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7l8-tetrahydronaphthalene-
c/s-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-
c/s-1-[6'-pyrrolodinoethoxy-3'-pyridyl]-2-phenyl-6-hydroxy-1,2,3,4-tetrahydronaphthalene;
1-(4'-pyrrolidinoethoxyphenyl)-2-(4"-fluorophenyl)-6-hydroxy-1,2,3,4-
tetrahydroisoquinoline;
c/s-6-(4-hydroxyphenyl)-5-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-5l6,7,8-
tetrahydro-naphthalene-2-ol; or
1-(4'-pyrrolidinolethoxyphenyl)-2-phenyl-6-hydroxy-1,2,3,4-tetrahydroisoquinoline
and a compound of Formula I;
a method for the treatment of osteoporosis which comprises administering to
a human or other animal with osteoporosis a combination of calcitonin and a
compound of Formula I;
a method for increasing muscle mass, which method comprises administering
to a human or other animal in need of such treatment an amount of a compound of
Formula I which is effective in promoting release of endogenous growth hormone;
and
a method for promoting growth in growth hormone deficient children which
comprises administering to a growth hormone deficient child a compound of Formula
I which is effective in promoting release of endogenous growth hormone.
This invention further provides a method for treating or preventing diseases
or conditions which may be treated or prevented by growth hormone which
comprises administering to a human or other animal in need of such treatment or
prevention an amount of a compound of Formula I which is effective in promoting
release of endogenous growth hormone.
In another aspect, this invention provides methods for treating or preventing
congestive heart failure, frailty associated with aging, and obesity which comprise
administering to a human or other animal in need of such treatment or prevention an
amount of a compound of Formula I which is effective in promoting release of
endogenous growth hormone; of the instant method it is preferred that the disease or
condition to be treated or prevented is congestive heart failure or frailty associated
with aging.
In another aspect, this invention provides methods for accelerating bone
fracture repair, attenuating protein catabolic response after a major operation,
reducing cachexia and protein loss due to chronic illness such as AIDS and cancer,
accelerating wound healing, and accelerating the recovery of bum patients or
patients having undergone major surgery, which comprise administering to a human
or other animal in need of such treatment an amount of a compound of Formula I
which is effective in promoting release of endogenous growth hormone; of the instant
method a preferred method of use is to accelerate bone fracture repair or for
accelerating the recovery of patients having undergone major surgery.
In yet another aspect, this invention provides methods for improving muscle
strength, mobility, maintenance of skin thickness, metabolic homeostasis and renal
homeostasis, which comprise administering to a human or other animal in need of
such treatment an amount of a compound of claim 1 which is effective in promoting
release of endogenous growth hormone.
The instant compounds promote the release of growth hormone which are
stable under various physiological conditions and may be administered parenterally,
nasally or by the oral route.
Detailed Description of the Invention
One of ordinary skill will recognize that ceain substituents listed in this
invention may have reduced chemical stability when combined with one another or
with heteroatoms in the compounds. Such compounds with reduced chemical
stability are not preferred.
In general the compounds of Formula I can be made by processes which
include processes known in the chemical arts for the production of compounds.
Certain processes for the manufacture of Formula I compounds are provided as
further features of the invention and are illustrated by the following reaction
schemes.
In the above structural formulae and throughout the instant application, the
following terms have the indicated meanings unless expressly stated otherwise:
The alkyl groups are intended to include those alkyl groups of the designated
length in either a straight or branched configuration which may optionally contain
double or triple bonds. Exemplary of such alkyl groups are methyl, ethyl, propyl,
isopropyl, butyl, sec-butyl, tertiary butyl, pentyl, isopentyl, hexyl, isohexyl, allyl,
ethynyl, propenyl, butadienyl, hexenyl and the like.
When the definition C0-alkyl occurs in the definition, it means a single
covalent bond.
The alkoxy groups specified above are intended to include those alkoxy
groups of the designated length in either a straight or branched configuration which
may optionally contain double or triple bonds. Exemplary of such alkoxy groups are
methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, tertiary butoxy, pentoxy,
isopentoxy, hexoxy, isohexoxy, allyloxy, 2-propynyloxy, isobutenyloxy, hexenyloxy
and the like.
The term "halogen" or "halo" is intended to include the halogen atoms
fluorine, chlorine, bromine and iodine.
The term "halogenated alky!" is intended to include an alkyl group as defined
hereinabove substituted by one or more halogen atoms as defined hereinabove.
The term "halogenated cycloalkyl" is intended to include a cycloalkyl group
substituted by one or more halogen atoms as defined hereinabove.
The term "aryl" is intended to include phenyl and naphthyl and aromatic 5-
and 6-membered rings with 1 to 4 heteroatoms or fused 5- or 6-membered bicyclic
rings with 1 to 4 heteroatoms of nitrogen, sulfur or oxygen. Examples of such
heterocyclic aromatic rings are pyridine, thiophene (also known as thienyl), furan,
benzothiophene, tetrazole, indole, N-methylindole, dihydroindole, indazole, Nformylindole,
benzimidazole, thiazole, pyrimidine, and thiadiazole.
The chemist of ordinary skill will recognize that certain combinations of
heteroatom-containing substituents listed in this invention define compounds which
will be less stable under physiological conditions (e.g., those containing acetal or
aminal linkages). Accordingly, such compounds are less preferred.
The expression "prodrug" refers to compounds that are drug precursors,
which following administration, release the drug in vivo via some chemical or
physiological process (e.g., a prodrug on being brought to the physiological pH is
converted to the desired drug form). Exemplery prodrugs upon cleavage release the
corresponding free acid, and such hydrolyzable ester-forming residues of the
compounds of this invention include but are not limited to carboxylic acid substituents
(e.g., R1 is -(CH2)qC(O)2X8 where X6 is hydrogen, or R2 or A1 contains carboxylic
acid) wherein the free hydrogen is replaced by (C1-C4)alkyl, (C2-
C12)alkanoyloxymethyl, (C4-C9)1-(alkanoyloxy)ethyl, 1-methyl-1-(alkanoyloxy)-ethyl
having from 5 to 10 carbon atoms, alkoxycarbonyloxymethyl having from 3 to 6
carbon atoms, 1-(alkoxycarbonyloxy)ethyl having from 4 to 7 carbon atoms, 1-
methyl-1-(alkoxycarbonyloxy)ethyl having from 5 to 8 carbon atoms, N-
(alkoxycarbonyl)aminomethyl having from 3 to 9 carbon atoms, 1-(N-
(alkoxycarbonyl)amino)ethyl having from 4 to 10 carbon atoms, 3-phthalidyl, 4-
crotonolactonyl, gamma-butyrolacton-4-yl, dS-N,N-(CrC2)alkylamino(C2-C3)alkyl
(such as (3-dimethylaminoethyl), carbamoyl-(C1-C2)alkyl,
alkylcarbamoyl-(C1-C2)alkyl and piperidino-, pyrrolidino- or morpholino(C2-C3)alkyl.
Other exemplary prodrugs release an alcohol of Formula I wherein the free
hydrogen of the hydroxyl substituent (e.g., R1 contains hydroxyl) is replaced by (C,-
C6)alkanoyloxymethyl, 1 -(((VCeJalkanoyloxyJethyl, 1 -methyl-1 -((Ct-CaJalkanoyloxy)
ethyl, (d-CeJalkoxycarbonyloxymethyl, N-(C1-C6)alkoxy-carbonylaminomethyl,
succinoyl, (CrCeJalkanoyl, a-amino(C1-C4)alkanoyl, arylacetyl and aaminoacyl,
or a-aminoacyl-a-aminoacyl wherein said a-aminoacyl moieties are
independently any of the naturally occurring L-amino acids found in proteins,
P(O)(OH)2, -P(O)(O(C1-C6)alkyl)2 or glycosyl (the radical resulting from detachment
of the hydroxyl of the hemiacetal of a carbohydrate).
Prodrugs of this invention where a carboxyl group in a carboxylic acid of
Formula (I) is replaced by an ester may be prepared by combining the carboxylic
acid with the appropriate alkyl halide in the presence of a base such as potassium
carbonate in an inert solvent such as DMF at a temperature of about 0°C to 100°C
for about 1 to about 24 hours. Alternatively, the acid is combined with the appropriate
alcohol as solvent in the presence of a catalytic amount of acid such as concentrated
sulfuric acid at a temperature of about 20°C to 120°C, preferably at reflux, for about
1 hour to about 24 hours. Another method is the reaction of the acid in an inert
solvent such as THF, with concomitant removal of the water being produced by
physical (e.g., Dean Stark trap) or chemical (e.g., molecular sieves) means.
Prodrugs of this invention where an alcohol function has been derivatized as
an ether may be prepared by combining the alcohol with the appropriate alkyl
bromide or iodide in the presence of a base such as potassium carbonate in an inert
solvent such as DMF at a temperature of about 0°C to 100°C for about 1 to about 24
hours. Alkanoylaminomethyl ethers may be obtained by reaction of the alcohol with a
bis-(atkanoylamino)methane in the presence of a catalytic amount of acid in an inert
solvent such as THF, according to a method described in US 4,997,984.
Alternatively, these compounds may be prepared by the methods described by
Hoffman et al. in J. Org. Chem. 1994, 59, p. 3530.
Certain of the above defined terms may occur more than once in the above
formula and upon such occurrence each term shall be defined independently of the
other.
Throughout the specification and appendent claims the following
abbreviations are used with the following meanings:
TRH Thyrotropin releasing hormone
TROC 2,2,2-Trichloroethoxycarbonyl
The compounds of the instant invention all have at least one asymmetric
center as noted by the asterisk in the structural Formula I, above. Additional
asymmetric centers may be present on the molecule depending upon the nature of
the various substituents on the molecule. Each such asymmetric center will produce
two optical isomers and it is intended that all such optical isomers, as separated,
pure or partially purified optical isomers, racemic mixtures or diastereomeric mixtures
thereof, be included within the scope of the instant invention. In the case of the
asymmetric center represented by the asterisk, it has been found that the absolute
stereochemistry of the more active and thus more preferred isomer is shown in
Formula IA. This preferred absolute configuration also applies to Formula I.
(Figure Removed) With the R4 substituent as hydrogen, the spatial configuration of the asymmetric
center corresponds to that in a D-amino acid. In most cases this is also designated
an R-configuration although this will vary according to the values of R3 and R4 used
in making R- or S-stereochemical assignments.
The instant compounds are generally isolated in the form of their
pharmaceutically acceptable acid addition salts, such as the salts derived from using
inorganic and organic acids. Examples of such acids are hydrochloric, nitric, sulfuric,
phosphoric, formic, acetic, trifluoroacetic, propionic, maleic, succinic, D-tartaric, Ltartaric,
malonic, methane sulfonic and the like. In addition, certain compounds
containing an acidic function such as a carboxy can be isolated in the form of their
inorganic salt in which the counter-ion can be selected from sodium, potassium,
lithium, calcium, magnesium and the like, as well as from organic bases.
The pharmaceutically acceptable salts are formed by taking about 1
equivalent of a compound of formula (I) and contacting it with about 1 equivalent of
the appropriate corresponding acid of the salt which is desired. Work-up and
isolation of the resulting salt is well-known to those of ordinary skill in the art.
The growth hormone releasing compounds of Formula I are useful in vitro as
unique tools for understanding how growth hormone secretion is regulated at the
pituitary level. This includes use in the evaluation of many factors thought or known
to influence growth hormone secretion such as age, sex, nutritional factors, glucose,
amino acids, fatty acids, as well as fasting and non-fasting states. In addition, the
compounds of this invention can be used in the evaluation of how other hormones
modify growth hormone releasing activity. For example, it has already been
established that somatostatin inhibits growth hormone release.
The compounds of Formula I can be administered to animals, including
humans, to release growth hormone in vivo. The compounds are useful for
treatment of symptoms related to GH deficiency; stimulate growth or enhance feed
efficiency of animals raised for meat production to improve carcass quality; to
increase milk production in dairy cattle; improvement of bone or wound healing and
improvement in vital organ function. The compounds of the present invention by
inducing endogenous GH secretion will alter body composition and modify other GHdependent
metabolic, immunologic or developmental processes. For example, the
compounds of the present invention can be given to chickens, turkeys, livestock
animals (such as sheep, pigs, horses, cattle, etc.), companion animals (e.g., dogs) or
may have utility in aquaculture to accelerate growth and improve the protein/fat ratio.
In addition, these compounds can be administered to humans in vivo as a diagnostic
tool to directly determine whether the pituitary is capable of releasing growth
hormone. For example, the compounds of Formula I can be administered in vivo to
children. Serum samples taken before and after such administration can be assayed
for growth hormone. Comparison of the amounts of growth hormone in each of
these samples would be a means for directly determining the ability of the patient's
pituitary to release growth hormone.
Accordingly, the present invention includes within its scope pharmaceutical
compositions comprising, as an active ingredient, at least one of the compounds of
Formula I in association with a pharmaceutically acceptable carrier. Optionally, the
pharmaceutical compositions can further comprise an anabolic agent in addition to at
least one of the compounds of Formula I or another compound which exhibits a
ifferent activity, e.g., an antibiotic growth permittant or an agent to treat
osteoporosis or with other pharmaceuticaify active maten'als wherein the combination
enhances efficacy and minimizes side effects.
Growth promoting and anabolic agents include, but are not limited to, TRH,
PTH, diethylstilbesterol, estrogens, G-agonists, theophylline, anabolic steroids,
enkephalins, E series prostaglandins, compounds disclosed in U.S. Patent No.
3,239,345, the disclosure of which is hereby incorporated by reference, e.g., zeranol;
compounds disclosed in U.S. Patent No. 4,036,979, the disclosure of which is hereby
incorporated by reference, e.g., sulbenox; and peptides disclosed in U.S. Patent No.
4,411,890, the disclosure of which is hereby incorporated by reference.
The growth hormone secretagogues of this invention in combination with
other growth hormone secretagogues such as the growth hormone releasing
peptides GHRP-6 and GHRP-1 as described in U.S. Patent No. 4,411,890, the
disclosure of which is hereby incorporated by reference, and publications WO
89/07110, WO 89/07111 and B-HT920 as well as hexarelin and the newly
discovered GHRP-2 as described in WO 93/04081 or growth hormone releasing
hormone (GHRH, also designated GRF) and its analogs or growth hormone and its
analogs or somatomedins including IGF-1 and IGF-2 or u-adrenergic agonists such
as clonidine or serotonin 5HTID agonists such as sumitriptan or agents which inhibit
somatostatin or its release such as physostigmine and pyridostigmine, are useful for
increasing the endogenous levels of GH in mammals. The combination of a GH
secretagogue of this invention with GRF results in synergistic increases of
endogenous growth hormone.
As is well known to those skilled in the art, the known and potential uses of
growth hormone are varied and multitudinous [See "Human Growth Hormone",
Strobel and Thomas, Pharmacological Reviews, 4_6_, pg. 1-34 (1994); T. Rosen et
al., Horm Res, 1995; 43: pp. 93-99; M. Degerblad et al., European Journal of
Endocrinology, 1995, 133: pp. 180-188; J. O. Jorgensen, European Journal of
Endocrinology, 1994, 130: pp. 224-228; K. C. Copeland et al., Journal of Clinical
Endocrinology and Metabolism, Vol. 78 No. 5. pp. 1040-1047; J. A. Aloi et al.,
Journal of Clinical Endocrinology and Metabolism, Vol. 79 No. 4, pp. 943-949; F.
Cordido et al., Metab. Clin. Exp., (1995), 44(6), pp. 745-748; K. M. Fairhall et al., J,
Endocrinol., (1995), 145(3), pp. 417-426; RM. Frieboes et al.,
Neuroendocrinology, (1995), 61(5), pp. 584-589; and M. Llovera et al., Int J.
Cancer, (1995), 61(1), pp. 138-141]. Thus, the administration of the compounds of
this invention for purposes of stimulating the release of endogenous growth hormone
can have the same effects or uses as growth hormone itself. These varied uses of
growth hormone may be summarized as follows: stimulating growth hormone
release in elderly humans; treating growth hormone deficient adults; preventing
catabolic side effects of glucocorticoids, treating osteoporosis, stimulating the
immune system, acceleration of wound healing, accelerating bone fracture repair,
treating growth retardation, treating congestive heart failure as disclosed in PCT
publications WO 95/28173 and WO 95/28174 (an example of a method for assaying
growth hormone secretagogues for efficacy in treating congestive heart failure is
disclosed in R. Yang et al., Circulation, Vol. 92, No. 2, p.262, 1995), treating acute
or chronic renal failure or insufficiency, treatment of physiological short stature,
including growth hormone deficient children, treating short stature associated with
chronic illness, treating obesity, treating growth retardation associated with Prader-
Willi syndrome and Turner's syndrome; accelerating the recovery and reducing
hospitalization of bum patients or following major surgery such as gastrointestinal
surgery; treating intrauterine growth retardation, skeletal dysplasia, hypercortisonism
and Cushings syndrome; replacing growth hormone in stressed patients; treating
osteochondrodysplasias, Noonans syndrome, sleep disorders, Alzheimer's disease,
delayed wound healing, and psychosocial deprivation; treating of pulmonary
dysfunction and ventilator dependency; attenuating protein catabolic response after
a major operation; treating malabsorption syndromes, reducing cachexia and protein
loss due to chronic illness such as cancer or AIDS; accelerating weight gain and
protein accretion in patients on TPN (total parenteral nutrition); treating
hyperinsulinemia including nesidioblastosis; adjuvant treatment for ovulation
induction and to prevent and treat gastric and duodenal ulcers; stimulating thymic
development and preventing age-related decline of thymic function; adjunctive
therapy for patients on chronic hemodialysis; treating immunosuppressed patients
and enhancing antibody response following vaccination; improving muscle strength,
increasing muscle mass, mobility, maintenance of skin thickness, metabolic
homeostasis, renal hemeostasis in the frail elderly; stimulating osteoblasts, bone
remodelling, and cartilage growth; treating neurological diseases such as peripheral
and drug induced neuropathy, Guillian-Barre Syndrome, amyotrophic lateral
sclerosis, multiple sclerosis, cerebrovascular accidents and demyelinating diseases;
stimulating the immune system in companion animals and treating disorders of aging
in companion animals; growth promotant in livestock; and stimulating wool growth in
sheep.
It will be known to those skilled in the art that there are numerous compounds
now being used in an effort to treat the diseases or therapeutic indications
enumerated above. Combinations of these therapeutic agents, some of which have
also been mentioned above, with the growth promotant, exhibit anabolic and
desirable properties of these various therapeutic agents. In these combinations, the
therapeutic agents and the growth hormone secretagogues of this invention may be
independently and sequentially administered or co-administered in dose ranges from
one one-hundredth to one times the dose levels which are effective when these
compounds and secretagogues are used singly. Combined therapy to inhibit bone
resorption, prevent osteoporosis, reduce skeletal fracture, enhance the healing of
bone fractures, stimulate bone formation and increase bone mineral density can be
effectuated by combinations of bisphosphonates and the growth hormone
secretagogues of this invention, see PCT publication WO 95/11029 for a discussion
of combination therapy using bisphosphonates and GH secretagogues. The use of
bisphosphonates for these utilities has been reviewed, for example, by Hamdy,
NAT, Role of Bisphosphonates in Metabolic Bone Diseases, Trends in
Endocrinol. Metab., 1993, 4, pages 19-25. Bisphosphonates with these utilities
include but are not limited to alendronate, tiludronate, dimethyl-APD, risedronate,
etidronate, YM-175, clodronate, pamidronate, and BM-210995 (ibandronate).
According to their potency, oral daily dosage levels of the bisphosphonate of
between 0.1 mg and 5 g and daily dosage levels of the growth hormone
secretagogues of this invention of between 0.01 mg/kg to 20 mg/kg of body weight
are administered to patients to obtain effective treatment of osteoporosis.
The compounds of this invention may be combined with a mammalian estrogen
agonist/antagonist. Any estrogen agonist/antagonist may be used as the second
compound of this invention. The term estrogen agonist/antagonist refers to
compounds which bind with the estrogen receptor, inhibit bone turnover and prevent
bone loss. In particular, estrogen agonists are herein defined as chemical compounds
capable of binding to the estrogen receptor sites in mammalian tissue, and mimicking
the actions of estrogen in one or more tissue. Estrogen antagonists are herein defined
as chemical compounds capable of binding to the estrogen receptor sites in
mammalian tissue, and blocking the actions of estrogen in one or more tissues. Such
activities are readily determined by those skilled in the art according to standard
assays including estrogen receptor binding assays, standard bone histomorphometric
and densitometer methods (see Eriksen E.F. et a!., Bone Histomorphometry, Raven
Press, New York, 1994, pages 1-74; Grier S.J. et. al., The Use of Dual-Energy X-Ray
Absorptiometry In Animals, Inv. Radiol., 1996, 31(1):50-62; Wahner H.W. and
Fogelman I, The Evaluation of Osteoporosis: Dual Energy X-Ray Absorptiometry in
Clinical Practice., Martin Dunitz Ltd., London 1994, pages 1-296). A variety of these
compounds are described and referenced below, however, other estrogen
agonists/antagonists will be known to those skilled in the art. A preferred
estrogen agonist/antagonist is droloxifene: (phenol, 3-{1-[4[2-(dimethylamino)ethoxy]-
phenylJ-2-phenyM-butenyl]-, (E)-) and associated compounds which are disclosed in
U.S. patent 5,047,431 (the disclosure of which is hereby incorporated by reference).
Another preferred estrogen agonist/antagonist is tamoxifen: (ethanamine,2-[-4-
(1,2-diphenyl-1-butenyl)phenoxy]-N,N-dimethyl, (Z)-2-, 2-hydroxy-1,2,3-propanetricarboxylate
(1:1)) and associated compounds which are disclosed in U.S. patent
4,536,516 (the disclosure of which is hereby incorporated by reference). Another
related compound is 4-hydroxy tamoxifen which is disclosed in U.S. patent 4,623,660
(the disclosure of which is hereby incorporated by reference).
Another preferred estrogen agonist/antagonist is raloxifene: (methanone, [6-
hydroxy-2-(4-hydroxyphenyl)benzo[b]thien-3-yl][4-[2-(1-piperidinyl)ethoxy]phenyl]-
.hydrochloride) and associated compounds which are disclosed in U.S. patent
4,418,068 (the disclosure of which is hereby incorporated by reference).
Another preferred estrogen agonist/antagonist is idoxifene: Pyrrolidine, 1-[-[4-
[[1-(4-iodophenyl)-2-phenyl-1-Butenyl]phenoxy]ethyl] and associated compounds
which are disclosed in U.S. patent 4,839,155 (the disclosure of which is hereby
incorporated by reference).
Other preferred estrogen agonist/antagonists include compounds as described
in commonly assigned U.S. patent no. 5,552,412 the disclosure of which is hereby
incorporated by reference. Especially preferred compounds which are described
therein are:
c/s-6-(4-fluoro-phenyl)-5-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-
(-)-c/s-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-
c/s-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6l7,8-tetrahydronaphthalene-
2-ol;
c/s-1-[6'-pyrrolodinoethoxy-3'-pyridyl]-2-phenyl-6-hydroxy-1,2,3,4-
tetrahydronaphthalene;
1-(4'-pytTolidinoethoxyphenyl)-2-(4l'-fluorophenyl)-6-hydroxy-1,2,3,4-
tetrahydroisoquinoline;
c/s-6-(4-hydroxyphenyl)-5-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-5,6,7,8-
tetrahydro-naphthalene-2-ol; and
1 -(4'-pyirolidinolethoxyphenyl)-2-phenyl-6-hydroxy-1,2,3,4-
tetrahydroisoquinoline.
Other estrogen agonist/antagonists are described in U.S. Patent 4,133,814 (the
disclosure of which is hereby incorporated by reference). U.S. Patent 4,133,814
discloses derivatives of 2-phenyl-3-aroyl-benzothiophene and 2-phenyl-3-
aroylbenzothiophene-1 -oxide.
The following paragraphs provide preferred dosage ranges for various antiresorpth/
e agents.
The amount of the anti-resorptive agent to be used is determined by its activity
as a bone loss inhibiting agent. This activity is determined by means of an individual
compound's pharmacokinetics and its minimal maximal effective dose in inhibition of
bone loss using a protocol such as those referenced above.
In general an effective dosage for the activities of this invention, for example
the treatment of osteoporosis, for the estrogen agonists/antagonists (when used in
combination with a compound of Formula I of this invention) is in the range of 0.01 to
200 mg/kg/day, preferably 0.5 to 100 mg/kg/day.
In particular, an effective dosage for droloxifene is in the range of 0.1 to 40
mg/kg/day, preferably 0.1 to 5 mg/kg/day.
In particular, an effective dosage for raloxrfene is in the range of 0.1 to 100
mg/kg/day, preferably 0.1 to 10 mg/kg/day.
In particular, an effective dosage for tamoxifen is in the range of 0.1 to 100
mg/kg/day. preferably 0.1 to 5 mg/kg/day."
In particular, an effective dosage for
c/s-€-(4-fluoro-phenyl)-5-[4-(2-piperidin-1-yl-€thoxy)-phenyl}-5,6,7,8-tetrahydronaphthalene-
(-)-c/s-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6,7,8-tetrahydronaphthalene-
c/s-6-phenyl-5-[4-(2-pyrrolidin-1-yl-ethoxy)-phenyl]-5,6l7,8-tetrahydronaphthalene-
c/s-1-l6'-pyrrolodinoethoxy-3'-pyridyl]-2-phenyl-6-hydroxy-1,2,3,4-
tetrahydronaphthalene;
1-(4'-pyrrolidinoethoxyphenyl)-2-(4"-fluorophenyl)-6-hydroxy-1,2,3,4-
tetrahydroisoquinoline;
c/s-6-(4-hydroxyphenyl)-5-[4-(2-piperidin-1-yl-ethoxy)-phenyll-5,6,7,8-
tetrahydro-naphthalene-2-ol; or
1 -(4'-pyrrolidinolethoxyphenyl)-2-phenyl-6-hydroxy-1,2,3,4-
tetrahydroisoquinoline is in the range of 0.0001 to 100 mg/kg/day, preferably 0.001 to
10 mg/kg/day.
In particular, an effective dosage for 4-hydroxy tamoxifen is in the range of
0.0001 to 100 mg/kg/day, preferably 0.001 to 10 mg/kg/day.
Compounds that have the ability to stimulate GH secretion from cultured rat
pituitary cells are identified using the following protocol. This test is also useful for
comparison to standards to determine dosage levels. Cells are isolated from
pituitaries of 6-week old male Wistar rats. Following decapitation, the anterior
pituitary lobes are removed into cold, sterile Hank's balanced salt solution without
calcium or magnesium (HBSS). Tissues are finely minced, then subjected to two
cycles of mechanically assisted enzymatic dispersion using 10 U/mL bacterial
protease (EC 3.4.24.4, Sigma P-6141) in HBSS. The tissue-enzyme mixture is
stirred in a spinner flask at 30 rpm in a 5% CO2 atmosphere at about 37°C for about
30 min, with manual trituration after about 15 min and about 30 min using a 10-mL
pipet. This mixture is centrifuged at 200 x g for about 5 min. Horse serum is added
to the supernatant to neutralize excess protease. The pellet is resuspended in fresh
protease, stirred for about 30 min more under the previous conditions, and manually
triturated, ultimately through a 23-gauge needle. Again, horse serum is added, then
the cells from both digests are combined, pelleted (200 x g for about 15 min),
washed, resuspended in culture medium and counted. Cells are plated at 6.0-
6.5x104 cells per cm2 in 48-well Costar dishes and cultured for 3-4 days in
Dulbecco's Modified Eagle Medium (0-MEM) supplemented with 4.5 g/L glucose,
10% horse serum, 2.5% fetal bovine serum, 1% non-essential amino acids, 100
U/mL nystatin and 50 mg/mL gentamycin sulfate before assaying for GH secretion.
Just prior to assay, culture wells are rinsed twice, then equilibrated for about
30 minutes in release medium (D-MEM buffered with 25 mM Hepes, pH 7.4 and
containing 0.5% bovine serum albumin at 37°C). Test compounds are dissolved in
DMSO, then diluted into pre-warmed release medium. Assays are run in
quadruplicate. The assay is initiated by adding 0.5 mL of release medium (with
vehicle or test compound) to each culture well. Incubation is carried out at about
37°C for about 15 minutes, then terminated by removal of the culture medium, which
is centrifuged at 2000 x g for about 15 minutes to remove cellular material. Rat
growth hormone concentrations in the supematants are determined by a standard
radioimmunoassay protocol using a rat growth hormone reference preparation
(NIDOK-rGH-RP-2) and rat growth hormone antiserum raised in monkey (NIDDKanti-
rGH-S-5) obtained from Dr. A. Parlow (Harbor-UCLA Medical Center, Torrence,
CA). Additional rat growth hormone (1.511/mg, #G2414, Scripps Labs, San Diego,
CA) is iodinated to a specific activity of approximately 30 uCi/ug by the chloramine T
method for use as tracer. Immune complexes are obtained by adding goat
antiserum to monkey IgG (Organon Teknika, Durham, NC) plus polyethylene glycol,
MW 10,000-20,000 to a final concentration of 4.3%; recovery is accomplished by
centrifugation. This assay has a working range of 0.08-2.5 ug rat growth hormone
per tube above basal levels. Active compounds typically stimulate growth hormone
release by greater than 1.4 fold. Reference: Cheng, K., Chan, W.-S., Barreto, Jr.,
A., Convey, E.M., Smith, R.G. 1989.
Assay for Exogenous! v-Stimulated Growth Hormone Release in the Rat after
Intravenous Administration of Test Compounds
Twenty-one day old female Sprague-Dawley rats (Charles River Laboratory,
Wilmington, MA) are allowed to acclimate to local vivarium conditions (24 °C, 12 hr
light, 12 hr dark cycle) for approximately 1 week before compound testing. Ail rats
are allowed access to water and a pelleted commercial diet (Agway Country Food,
Syracuse NY) ad libitum. The experiments are conducted in accordance with the
NIH Guide for the Care and Use of Laboratory Animals.
On the day of the experiment, test compounds are dissolved in vehicle
containing 1% ethanol, 1mM acetic acid and 0.1% bovine serum albumin in saline.
Each compound is tested with n=3. Rats are weighed and anesthetized via
intraperitoneal injection of sodium pentobarbital (Nembutol, 50 mg/kg body weight).
Fourteen minutes after anesthetic administration, a blood sample is taken by nicking
the tip of the tail and allowing the blood to drip into a microcentrifuge tube (baseline
blood sample, approximately 100 pi). Fifteen minutes after anesthetic
administration, test compound is delivered by intravenous injection into the tail vein,
with a total injection volume of 1 ml/kg body weight. Additional blood samples are
taken from the tail at 5, 10 and 15 minutes after compound administration. Blood
samples are kept on ice until serum separation by centrifugation (1430xg for 10
minutes at 10°C). Serum is stored at -80°C until serum growth hormone
determination by radio-immunoassay as described above and below.
Assessment of Exogenously-Stimulated Growth Hormone Release in the Dog after
Oral Administration
On the day of experimentation, the test compound is weighed out for the appropriate
dose and dissolved in water. Doses are delivered at a volume of 0.5 ml/kg by
gavage to 4 dogs for each dosing regimen. Blood samples (2 ml) are collected from
the jugular vein by direct vena puncture pre-dose and at 0.08, 0.17, 0.25, 0.5, 0.75,
1, 2, 4, 6, and 8 hours post dose using 2 ml vacutainers containing lithium heparin.
The prepared plasma is stored at -20 °C until analysis.
Measurement of Canine Growth Hormone
Canine growth hormone concentrations are determined by a standard
radioimmunoassay protocol using canine growth hormone (antigen for iodination and
reference preparation AFP-1983B) and canine growth hormone antiserum raised in
monkey (AFP-21452578) obtained from Dr. A. Parlow (Harbor-UCLA Medical
Center, Torrence, CA). Tracer is produced by chloramine T-iodination of canine
growth hormone to a specific activity of 20-40 uCi/ug. Immune complexes are
obtained by adding goat antiserum to monkey IgG (Organon Teknika, Durham, NC)
plus polyethylene glycol, MW 10,000-20,000 to a final concentration of 4.3%;
recovery is accomplished by centrifugation. This assay has a working range of 0.08-
2.5 ug canine GH/tube.
The compounds of this invention can be administered by oral, parenteral
(e.g., intramuscular, intraperitoneal, intravenous or subcutaneous injection, or
implant), nasal, vaginal, rectal, sublingual, or topical routes of administration and can
be formulated with pharmaceutically acceptable carriers to provide dosage forms
appropriate for each route of administration.
Solid dosage forms for oral administration include capsules, tablets, pills,
powders and granules. In such solid dosage forms, the active compound is admixed
with at least one inert pharmaceutically acceptable carrier such as sucrose, lactose,
or starch. Such dosage forms can also comprise, as is normal practice, additional
substances other than such inert diluents, e.g., lubricating agents such as
magnesium stearate. In the case of capsules, tablets and pills, the dosage forms
may also comprise buffering agents. Tablets and pills can additionally be prepared
with enteric coatings.
Liquid dosage forms for oral administration include pharmaceutically
acceptable emulsions, solutions, suspensions, syrups, the elixirs containing inert
diluents commonly used in the art, such as water. Besides such inert diluents,
compositions can also include adjuvants, such as wetting agents, emulsifying and
suspending agents, and sweetening, flavoring and perfuming agents.
Preparations according to this invention for parenteral administration include
sterile aqueous or non-aqueous solutions, suspensions, or emulsions. Examples of
non-aqueous solvents or vehicles are propylene glycol, polyethylene glycol,
vegetable oils, such as olive oil and com oil, gelatin, and injectable organic esters
such as ethyl oleate. Such dosage forms may also contain adjuvants such as
preserving, wetting, emulsifying, and dispersing agents. They may be sterilized by,
for example, filtration through a bacteria-retaining filter, by incorporating sterilizing
agents into the compositions, by irradiating the compositions, or by heating the
compositions. They can also be manufactured in the form of sterile solid
compositions which can be dissolved in sterile water, or some other sterile injectable
medium immediately before use.
Compositions for rectal or vaginal administration are preferably suppositories
which may contain, in addition to the active substance, excipients such as coca
butter or a suppository wax.
Compositions for nasal or sublingual administration are also prepared with
standard excipients well known in the art.
The dosage of active ingredient in the compositions of this invention may be
varied; however, it is necessary that the amount of the active ingredient be such that
a suitable dosage form is obtained. The selected dosage depends upon the desired
therapeutic effect, on the route of administration, and on the duration of the
treatment. Generally, dosage levels of between 0.0001 to 100 mg/kg of body weight
daily are administered to humans and other animals, e.g., mammals, to obtain
effective release of growth hormone.
A preferred dosage range is 0.01 to 5.0 mg/kg of body weight daily which can
be administered as a single dose or divided into multiple doses.
The preparation of the compounds of Formula I of the present invention can
be carried out in sequential or convergent synthetic routes. Syntheses detailing the
preparation of the compounds of Formula I in a sequential manner are presented in
the reaction schemes shown hereinbelow.
Many protected amino acid derivatives are commercially available, where the
protecting groups Pit, Z100 and Z200 are, for example, BOC, CBZ, benzyl,
ethoxycarbonyl groups, CF3C(O)-, FMOC, TROC, trityl or tosyl. Other protected
amino acid derivatives can be prepared by literature methods. Some 3-oxo-2-
carboxyl pyrrolidines, and 4-oxo-3-carboxyl piperidines are commercially available,
and many other related pyrrolidines and 4-substituted piperidines are known in the
literature.
Many of the schemes illustrated below describe compounds which contain
protecting groups Prt, Z100 or Z200. Benzyloxycarbonyl groups can be removed by a
number of methods including, catalytic hydrogenation with hydrogen in the presence
of a palladium or platinum catalyst in a protic solvent such as methanol. Preferred
catalysts are palladium hydroxide on carbon or palladium on carbon. Hydrogen
pressures from 1-1000 psi may be employed; pressures from 10 to 70 psi are
preferred. Alternatively, the benzyloxycarbonyl group can be removed by transfer
hydrogenation.
Removal of BOC protecting groups can be carried out using a strong acid
such as trifluoroacetic acid or hydrochloric acid with or without the presence of a
cosolvent such as dichloromethane, ethyl acetate, ether or methanol at a
temperature of about -30 to 70°C, preferably about -5 to about 35"C.
Benzyl esters of amines can be removed by a number of methods including,
catalytic hydrogenation with hydrogen in the presence of a palladium catalyst in a
protic solvent such as methanol. Hydrogen pressures from 1-1000 psi may be
employed; pressures from 10 to 70 psi are preferred. The addition and removal of
these and other protecting groups are discussed by T. Greene in Protective Groups
in Organic Synthesis, John Wiley & Sons, New York, 1981.
SCHEME 3: The esters of formula 6 can be converted to intermediate acids of
formula 13 by a number of methods known in the art; for example, methyl and ethyl
esters can be hydrolyzed with lithium hydroxide in a protic solvent such as aqueous
methanol or aqueous THF at a temperature of about -20° to 120°C, preferably about
0° to 50°C. In addition, removal of a benzyl group can be accomplished by a number
of reductive methods including hydrogenation in the presence of platinum or
palladium catalyst in a protic solvent such as methanol. Coupling the acid 13 to
amine 16 generates the intermediates of formula 14. Transformation of 14 to 15 can
be achieved by removal of the protecting group Z200.
SCHEME 22: Alkylation of compounds of formula 25 with an allylic acetate in the
presence of a suitable catalyst such as palladium tetrakis(triphenylphosphine) affords
compounds of formula 74. Deprotection of the nitrogen affords compounds of
formula 75, see Tetrahedron (50) p. 515, 1994 for a detailed discussion.
SCHEME 23: Treatment of a ketodiester of formula 76 with an alkyl halide in the
presence of a base such as sodium hydhde followed by acid-catalyzed hydrolysis
and decarboxylation, followed by esterification with methyliodide and a suitable base
affords a compound of formula 77. Reaction of a compound of formula 77 with a
suitable aldehyde such as formaldehyde and benzylamine affords a compound of
formula 78. Reaction of a compound of formula 78 with a hydrazine generates chiral
compounds of formula 79. Deprotection of the nitrogen affords compounds of
(Figure Removed) SCHEME 27: Treatment of the amine of formula 23a with an acid such as 1 in the
presence of EDC and HOAT in a suitable solvent provides keto-esters of formula
23b. The keto-ester 23b can be treated with a salt of hydrazine in the presence of
sodium acetate in refluxing ethanol to give hydrazines of formula 23c. Deprotection
under suitable conditions gives amines of formula 4. Coupling of intermediates of
formula 4 to amino acids of formula 5 can be effected as described above to give
intermediates of formula 6. Deprotection of amine 6 affords compounds of formula
The following examples are provided for the purpose of further illustration
only and are not intended to be limitations on the disclosed invention.
General Experimental Procedures:
Amicon silica 30 i^M, 60 A pore size, was used for column chromatography. Melting
points were taken on a Buchi 510 apparatus and are uncorrected. Proton and
carbon NMR spectra were recorded on a Varian XL-300, Bruker AC-300, Varian
Unity 400 or Bruker AC-250 at 25 °C . Chemical shifts are expressed in parts per
million down field from trimethylsilane. Particle beam mass spectra were obtained
on a Hewlett-Packard 5989A spectrometer using ammonia as the source of chemical
ionization. For initial sample dissolution, chloroform or methanol was employed.
Liquid secondary ion mass spectra (LSIMS) were obtained on a Kratos Concept-18
high resolution spectrometer using cesium ion bombardment on a sample dissolved
in a 1:5 mixture of dithioerythritol and dithiothreitol or in a thioglycerol matrix. For
initial sample dissolution chloroform or methanol was employed. Reported data are
sums of 3-20 scans calibrated against cesium iodide. TLC analyses were performed
using E. Merck Kieselgel 60 F254 silica plates visualized (after elution with the
indicated solvent(s)) by staining with 15% ethanolic phosphomolybdic acid and
heating on a hot plate.
General Procedure A (Peptide coupling using EDC): A 0.2-0.5 M solution of the
primary amine (1.0 equivalent) in dichloromethane (or a primary amine hydrochloride
and 1.0-1.3 equivalents of triethylamine) is treated sequentially with 1.0-1.2
equivalents of the carboxylic acid coupling partner, 1.5-1.8 equivalents
hydroxybenzotriazole hydrate (HOST) or HOAT and 1.0-1.2 equivalents
(stoichiometrically equivalent to the quantity of carboxylic acid) 1-(3-
dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and the mixture is
stirred overnight in an ice bath (the ice bath is allowed to warm, thus the reaction
mixture is typically held at about 0-20 °C for about 4-6 h and about 20-25 *C for the
remaining period). The mixture is diluted with ethyl acetate or other solvent as
specified, and the resulting mixture washed twice with 1N NaOH, twice with 1N HCI
(if the product is not basic), once with brine, dried over Na2SC>4, and concentrated
giving the crude product which is purified as specified. The carboxylic acid
component can be used as the dicyclohexylamine salt in coupling to the primary
amine or hydrochloride of the latter; in this case no triethylamine is employed.
Example 1
2-Amino-M|-{1(R)-benzylQxymethyl-2-[3a-(R)-(4-fluoro-ben^yl)-2-methyl-3-oxohydrochloride
and
2-ArnJno-N-{1(R)-benzyloxymethyl-2-[3a-(S)-(4-fluoro-benzyl)-2-methyl-3-oxohydrochloride
A. 4-QxQ-piperidine-1r3-dicarpoxy|ic apid 1-tert-butyl egter 3-ethyl ester
A mixture of 8.00 g (38.5 mmol) of 4-oxo-piperidine-3-carboxyllc acid ethyl ester
hydrochloride, 9.23 g (42.4 mmol) of di-tert-butyldicarbonate, and 3.89 g (33.5 mmol)
of triethylamine in 150 ml of THF was stirred at room temperature for about 72 h.
The mixture was concentrated and the residue was dissolved in ethyl acetate and
washed three times each with 10% aqueous HCI, saturated aqueous sodium
bicarbonate solution, and brine, dried over MgSO4, and concentrated to give 10.0 g
of 1A as a white solid. MS (Cl, NHa) 272 (MH+).
B. 3-(R.S)-(4-Fluoro-benzyl)-4-oxo-piperidine-1.3-dicarboxy|ic acid 1-tert-butyl
ester 3-ethyl ester
To a solution of 2.00 g (7.4 mmol) 1A in 10 mL of DMF was added 282 mg (7.4
mmol) of sodium hydride (60% oil dispersion) and the mixture was stirred at room
temperature for about 15 min. A solution of 1.39 g (7.4 mmol) 4-fluorobenzyl
bromide in 7 mL of DMF was added to the stirring solution and the mixture was
stirred for about 72 h at room temperature. The mixture was diluted with ethyl
acetate and washed once with water and four times with brine, dried over MgSO4,
and concentrated to give 2.8 g of 1B. MS (Cl, NHs) 380 (MH+).
C 3a-(R.S)-(4-Fluoro-benzyl)-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolof4.3-
c]pyridine-5-carbQxvlic acid tert-butyl ester
A mixture of 2.54 g (6.7 mmol) of 18 and 309 mg (6.7 mmol) of methylhydrazine in
100 mL of ethanol was heated at reflux for about 8 h. The mixture was concentrated
and the residue was dissolved in 100 ml toluene and heated at reflux for about 17 h.
The mixture was concentrated and the residue was purified by silica gel
chromatography using an elution gradient of (18:82 v/v ethyl acetate:hexane) to
(75:25 v/v ethyl acetate:hexane) to give 1.0 g of 1C as a clear colorless oil. MS (Cl,
NH3) 362 (MH+).
D. 3a-(R.S)-(4-Fluoro-benzyl)-2-methyl-2.3a.4.5.6.7-hexahydro-pyrazolo[4.3-
c]pyrid(n-3-one trifluoroacetate
To 1.00 g (2.8 mmol) of 1C was added 10 ml of trifluoroacetic acid at about 0 °C
and the mixture was stirred for about 1 h. Ethyl acetate was added and the mixture
was concentrated to give 1.0 g of 1D. MS (Cl, NH3) 263 (MH+).
E. (R)-3-Benzyloxy-2-(2-tert-butoxycarbonylamino-2-methyl-propionylamino)-
propionic acid
To 1.83 g (6.2 mmol) of N-t-BOC-O-benzyl-D-serine in 35 mL of DMF was added
1.02g (7.4 mmol) of potassium carbonate followed by 0.92g (6.5 mmol) of
iodomethane. The mixture was stirred overnight at about 24 °C under an
atmosphere of nitrogen. The reaction mixture was diluted with 200 ml of water, and
extracted three times with ethyl acetate. The combined organics were washed five
times with water and once with brine, dried over MgSO4 and concentrated. The
crude (R)-3-beruyloxy-2-tert-butoxycarbonyl-amino-propionic acid methyl ester was
dissolved in 15 ml of cold trifluoroacetic acid at about 0 °C and the mixture was
stirred for about 2 h. The mixture was concentrated and the residue was diluted with
1N NaOH and extracted three times with ethyl acetate. The combined organic
extracts were washed with brine and dried over Na2SO4 to give 0.84 g (4.02 mmol)
of the resulting (R)-2-amino-3-benzyloxy-propionic acid methyl ester which was
coupled to 0.81 g (4.02 mmol) of N-t-BOC-a-methylalanine to give 1.80 g of (R)-3-
benzyloxy-2-(2-tert-butoxycarbonylamino-2-methyl-propionylamino)-propionic acid
methyl ester. The crude product was dissolved in 20 ml of 4:1 THF:water and a
solution of 335 mg (7.98 mmol) of lithium hydroxide hydrate in 1 mL of water was
added to the solution and the mixture was stirred overnight at room temperature.
The mixture was concentrated and the residue was diluted with ethyl acetate and
acidified with aqueous HCI and extracted three times with ethyl acetate. The organic
extracts were combined and washed once with brine, dried over Na2SO4 and
concentrated to give 1.60 g of 1E as an oil which solidified on standing. 1H NMR
(CDCI3 300 MHz) 8 7.30 (m, 5H). 7.10 (d, 1H), 5.07 (bs, 1H), 4.68 (m, 1H), 4.53 (q,
2H) 4.09 (m, 1H), 3.68 (m, 1H), 1.3-1.5 (m, 15H).
F. (1-{irR)-Benzvloxvmethvl-2-f3a-rR.SW4-fluoro-ben2yn-2-methyl-3-oxo.
2.3.3a.4.6.7-hexahydro-pvrazolof4.3-clpyridin-5-vl]-2-oxo-ethylcarbamoyl>-1-mefhylethyl)-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 193 mg (0.51 mmol) of 1D
and 196 mg (0.51 mmol) of 1E were coupled to give a mixture of diastereomers.
The residue was purified by silica gel chromatography using an elution gradient of
(1:1 v/v ethyl acetate: hexane) to 100% ethyl acetate to give 60 mg of less polar 1F
isomer 1 and 100 mg of more polar 1F isomer 2. MS (Cl, NHa) 624 (MH+) for both
isomers.
G. 2-Amin(>N^imVbenzyloxymethyl-2-[3a-rRW4-fluoro-benzvn-2-methyl-3-
ethyl}-isobutyramide hydrochloride
To 60 mg (0.10 mmol) of 1F isomer 1 in 10 ml of ethanol was added 4 mL of
concentrated HCI and the mixture was stirred at room temperature for about 2 h.
The mixture was concentrated and the residue was precipitated from ethanol/hexane
to give 50 mg of 1G isomer 1 as a white powder. MS (Cl, NH3) 524 (MH+). 1HNMR
(CD3OD): (partial) 8 7.32 (m, 5 H), 7.12 (m. 2 H), 6.91 (m, 2 H), 5.15 (m, 1 H), 4.54
(s, 2 H), 3.78 (m, 2 H)3.02 (m, 7 H), 2.66 (m, 2 H), 1.57 (s, 6 H).
H. 2-Amino-N41fR)-benzyloxymethyl-2-[3a-(SW4-fluoro-benzyl)-2-methyl-3-oxQ-
2,3,3a.4,6f7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl]-2-oxoethyl}-
isobutyramide hydrochloride
To 100 mg (0.16 mmol) of 1F isomer 2 in 10 mL of ethanol was added 4 ml of
concentrated HCI and the mixture was stirred at room temperature for about 2 h.
The mixture was concentrated and the residue was precipitated from ethanol/hexane
to give 60 mg of 1H isomer 2 as a white powder. MS (Cl, NHa) 524 (MH+). 1HNMR
(CDaOO): (partial) 5 7.32 (m, 5 H), 7.08 (m, 2 H), 6.95 (m, 2 H). 6.80 (m, 2 H), 5.30
(m, 1 H), 4.61 (m, 3 H), 3.80 (m, 2 H), 2.58 (mr3 H), 1.58 (s, 6 H).
Example 2
2-Aminp-N-[2-[3^-(R.S)-(4-fluoro-benzyl)-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolp(
4.3-c]pyridin-5-yl]-irR)-MH-indol-3-ylmethyl)-2-Qxo-ethyq-isobutyramide
hydrochloride
A. (R)-2-Amipo-3-[(1H-indol-3-yl)-propionic acid methyl ester
To 4.92 g (16.2 mmol) of N-a-t-BOC-D-tryptophan in 100mL of DMF was added 2.46
g (17.8 mmol) of potassium carbonate followed by 2.41 g (17.0 mmol) of
iodomethane, and the mixture was stirred overnight at 24°C under an atmosphere of
nitrogen. The reaction mixture was diluted with water, and extracted three times with
ethyl acetate. The combined organics were washed five times with 500 ml of water
and once with brine, dried over MgSO4 and concentrated to give 4.67 g of a white
solid. To the crude (R)-2-tert-butoxycarbonylamino-3-(1H-indol-3-yl)-propionic acid
methyl ester was added 15 ml of cold trifluoroacetic acid at about 0 °C and the
mixture was stirred for about 2 h. The mixture was concentrated and the residue
was diluted with 1N NaOH and extracted three times with ethyl acetate. The
combined organic extracts were washed with brine and dried over Na2SO4 to give
(R)-2-amino-3-(1H-indol-3-yl)-propionic acid methyl ester as an orange oil in
quantitative yield.
B. (RV2-r2-tert-Butoxycarbonylamino-2-methyl-proDionvlaminoV3-(1H-indol-3-
yl)-propionic acid methyl ester.
The crude product from 2A 1.55 g (7.1 mmol) was coupled to 1.44 g (7.1 mmol) of
N-t-BOC-a-methylalanine according to Procedure A to give an oil which was purified
by silica gel chromatography using a gradient of 10%, 20%, 30%, 40% and 50%
ethyl acetate in hexane to elute. Recovered 1.32 g of (R)-2-(2-tertbutoxycarbonylamino-
2-methyl-propionylamino)-3-( 1 H-indol-3-yl)-propionic acid
methyl ester.
C (R)-2-(2-tert-ButQxycarbonylamino-2-methyl-propionylamino)-3-(1H-indol-3-
yl)-propionic acid
To a solution of 1.03 g (2.64 mmol) of 28 in 10 ml of THF was added 381 mg (9.1
mmol) of lithium hydroxide hydrate in 2 ml of water and the mixture was stirred
overnight at room temperature. Excess THF was removed by evaporation, and the
basic aqueous mixture was extracted three times with ethyl acetate, and then
acidified to pH 4 with dilute acetic or hydrochloric acid. The product was extracted
with ethyl acetate and the combined organic extracts were washed with brine, dried
over MgSO4 and evaporated to give 1.03 g of 2C as an orange foam. MS (Cl, NH3)
390 (MH+). 1H NMR (CDCIs 300 MHz) 8 7.61 (d. 1H), 7.48 (d, 1H), 7.27 (t, 1H),
7.10 (t, 1H), 4.81 (bs, 1H), 3.35 (m, 1H), 1.49 (s, 6H). 1.32 (s, 9H).
D. {1-[2-[3a-(R.SH4-Fluoro-benzylV2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolQ[
4.3-c]pyridin-5-yl]-1-(R)-(1H-indol-3-ylmethyl)-2-oxo-ethylcarbamoyl]-1-
methyl-ethyl}-carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 193 mg (0.51 mmol) of 1D
and 200 mg (0.51 mmol) of 2C were coupled and the residue was purified by silica
gel chromatography using an elution gradient of (1:1 v/v ethyl acetate: hexane) to
100% ethyl acetate to give 230 mg of 20. MS (Cl, NHs) 633 (MH+).
E. 2-Amino-N-[2-[3a-(RrS)-(4-fluoro-benzyl)-2-methyl-3-oxo-2.3.3a.4.6.7-
hexahydro-pyrazolQ[4.3-c]pyridin-5-yl]-1(RH1H-indol-3-ylmethyn-2-oxo-ethynisobutyramide
hydrochloride
To 230 mg (0.36 mmol) of 20 in 10 mL of ethanol was added 4 mL of concentrated
HCI and the mixture was stirred at room temperature for about 2 h. The mixture was
concentrated and the residue was precipitated from ethanol/hexane to give 130 mg
of 2E as a white powder. MS (Cl, NHs) 533 (MH+). 1HNMR (CDsOD): (partial) 6
7.79 (d, 1 H), 7.48 (m, 1 H), 7.33 (m, 2 H), 7.19 - 6.77 (m, 7 H), 6.54 (m, 1 H), 5.17
(m, 1 H), 4.02 (m, 1 H), 3.11 - 2.68 (m, 6 H), 2.47 (m, 2 H), 2.03 (m, 2 H), 1.59 (m, 6
-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahvdro-DvrazolQ[43-
c]pyridin-5-yl)-1R-(1H-indol-3-ylmethyl)-2-Qxo-ethyl]-isobutyramide
A. 4-Oxo-piperidine-1.3-dicarboxylic acid 1-tert-butyl ester 3-methyl ester
To a mixture of 7.00 g (36.2 mmol) of 4-oxo-piperidine-3-carboxylic acid methyl ester
and 8.82 g (72.3 mmol) of 4,4-dimethylaminopyridine in 200 ml of methylene
chloride at about 0 °C was added a solution of 7.88 g (36.2 mmol) of di-tertbutyldicarbonate
in 150 ml of methylene chloride over about 30 min. The mixture
was warmed to room temperature and then stirred for about 17 h. The mixture was
concentrated and the residue was diluted with chloroform and washed three times
each with 10% aqueous HCI, saturated aqueous sodium bicarbonate solution and
brine, dried over MgSO4 and concentrated to give 9.18 g of a clear yellow oil.
B. 3-(R,S)-Ben2yl-4-oxo-piperidine-1.3-dicarboxylic acid 1-tert-butyl ester 3-
methyl ester
To a solution of 5.00 g (19.4 mmol) 3A in 10 mL of DMF was added 745 mg (7.4
mmol) of sodium hydride (60% oil dispersion) and the mixture was stirred at room
temperature for about 15 min. A solution of 3.32 g (19.4 mmol) benzylbromide in 15
mL of DMF was added to the stirring solution by cannula and the mixture was stirred
for about 42 h at room temperature. The mixture was diluted with ethyl acetate and
washed once with water and four times with brine, dried over MgSO4, and
concentrated to give 6.0 g of 3B as a yellow oil. MS (Cl, NHa) 348 (MH+).
C. 3a-fR.S)-Benzyl-2-methyl-3-oxo-2.3.3a4.6.7-hexahydrQ-pyrazolo[4.3-c]-
pyridine-5-carboxylic acid tert-butyl ester
A mixture of 4.00 g (11.5 mmol) of 3B and 530 mg (11.5 mmol) of methylhydrazine
in 100 mL of ethanol was heated at reflux for about 8 h. The mixture was
concentrated and the residue was dissolved in 100 mL toluene and heated at reflux
for about 17 h. The mixture was concentrated and the residue was purified by silica
gel chromatography using an elution gradient of (15:85 v/v ethyl acetate:hexane) to
(75:25 v/v ethyl acetate:hexane) to give 2.6 g of 3C as a dear colorless oil. MS (Cl,
NH3) 344 (MH+).
D. 3a-(R,S)-Benzyl-2-methyl-2.3ar4,5.6.7-hexahydro-pyrazolo[4.3-c]pyridin-3-
one
To 2.60 g (7.6 mmol) of 3C was added 20 ml of trifluoroacetic acid at about 0 °C
and the mixture was stirred for about 2.5 h. Ethyl acetate was added and the
solution was washed with 6N NaOH, dried over MgSO4 and concentrated to give 1.8
g of 3D. MS (Cl, NHs) 244 (MH+).
E. {1-[2-(3a-(R.S)-Benzyl-2-methyl-3-oxo-2.3.3a,4,6,7-hexahydro-pyrazolo[4,3-
c]pyridin-5-yl)-1R-(1H-indol-3-ylmethyl)-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 125 mg (4.6 mmol) of 3C
and 1.75 g (0.51 mmol) of 2C were coupled and the residue was purified by silica gel
chromatography using an elution gradient of (6:4 v/v ethyl acetate:hexane) to 7%
methanol in ethyl acetate to give 150 mg of 3E.
F. 2-Amino-N-[2-(3a-m.S)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-q]pyridin-5-yl)-1R-(1H-indol-3-ylmethyl)-2-oxo-ethyl]-isobutyramide
hydrochloride
To 150 mg (0,24 mmol) of 3E in 15 mL of ethanol was added 5 mL of concentrated
HCI and the mixture was stirred at room temperature for about 3 h. The mixture was
concentrated and the residue was crystallized from ethanol/hexane to give 100 mg of
3F. MS (Cl, NH3) 515 (MH+). 1HNMR (CDaOD): 8 7.20 - 6.91 (m, 9 H), 6.56 (m. 1),
5.17 (m, 1 H), 4.05 (m, 1 H), 2.96 (s, 3 H), 2.62 (m, 1 H), 2.38 (m, 1 H), 2.06 (m, 2
H), 1.61 (m, 8H).
Example 4
2-Amino-N-[2-(3a-(R)-benzyl-2-methyl-3-oxo-2.3,3a.4,6,7-hexahydro-pyrazolo[4,3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride and
2-Amino-N-[2- c]pyridin-5-ylV1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
A. {1-[2-(3a-(R.S)-Benzyl-2-methyl-3-oxo-2.3.3a,4,6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-y|)-1-(R)-benzyloxymethyl-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 1.12 g (4.6 mmol) of 3C
and 1.75 g (0.51 mmol) of 1E were coupled to give a mixture of diastereomers. The
residue was purified by silica gel chromatography using an elution gradient of (1:1
v/v ethyl acetate:hexane) to 100% ethyl acetate to give 350 mg of less polar 4A
isomer 1 and 250 mg of more polar 4A isomer 2. MS (Cl, NHa) 606 (MH+) for both
isomers.
B. 2-Amino-N-[2-(3a-(RVbenzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-c]pvridin-5-vn-1-m)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
hydrochloride
To 250 mg (0.41 mmol) of 4A isomer 1 in 15 ml_ of ethanol was added 5 ml of
concentrated HCI and the mixture was stirred at room temperature for about 5 h.
The mixture was concentrated and the residue was precipitated from ethanol/hexane
and dried under vacuum to give 130 mg of 4B isomer 1. MS (Cl, NHa) 506 (MH+).
1HNMR (CD3OD): 5 7.33 (m, 5 H), 7.14 (m, 5 H), 5.22 (m, 1 H), 4.57 (m, 3 H), 3.80
(m, 2 H) 3.14 (m, 1 H), 3.04 (s, 3 H), 2.96 (m, 2 H), 2.61 (m, 2 H), 1.63 (m, 7 H).
C. 2-Amino-N-[2-(3a-(S)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4,3-c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
hydrochloride
To 250 mg (0.41 mmol) of 4A isomer 2 in 15 mL of ethanol was added 5 ml of
concentrated HCI and the mixture was stirred at room temperature for about 5 h.
The mixture was concentrated and the residue was precipitated from ethanol/hexane
and dried under vacuum to give 120 mg of 4C isomer 2. MS (Cl, NH3) 506 (MH+).
1HNMR (CDaOD): 8 7.31 (m, 5 H), 7.13 (m, 5 H), 6.78 (m, 1 H), 5.28 (m, 1 H), 4.62
(m, 3 H), 3.81 (M, 2 H), 3.14 (m, 1 H), 2.62 (m, 3 H), 1.58 (m, 7 H).
D. 2-Amino-N-[2-(3a-(R)-benzyl-2-methyl-3-oxo-2r3.3a.4,6f7-hexahydropvrazolo[
4.3-clpyridin-5-yh-1-rR)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
methanesulfonate
Saturated aqueous sodium bicarbonate was added to 3.60 g (6.6 mmol) of 4B
isomer 1 and the mixture was extracted with ethyl acetate. The organic layer was
dried over MgSO4 and concentrated. The residue was dissolved in ethyl acetate,
cooled to about 0 °C and 0.43 ml (6.6 mmol) of methane-sulfonic acid was added
and the mixture was stirred for about 0.5 h. Hexane (200 mL) was added to the
solution and the mixture was stirred for about 1h and filtered to give 3.40 g of a white
solid. The solid was recrystallized from 3% aqueous ethyl acetate to give 2.55 g of
4D isomer 1 as a white crystalline solid. MS (Cl, NHa) 506 (MH+).
Example 5
2-Amino-N-[1-f3a-fR)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridine-5-Qarbonyl)-4-phenyl-(R)-butyl]-isobutyramidehydrochloride and
2-Amino-N-[1-(3a-(S)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridine-5-Qarbonyl)-4-phenyl-(R)-butyl]-isobutyramide hydrochloride
A. 2-Oxo-5f6-diphenyi-3-(3-phenyl-allyl)-morpholine-4-carboxylic acid t-butyl
To an about -78°C solution of 13.8 g (70.0 mmol) of cinnamyl bromide and 4.94 g
(14.0 mmol) of t-butyl-(2S,3R)-(+)-6-oxo-2,3-diphenyl-4-morpholine carboxylate in
350 ml of anhydrous THF was added 28 ml (28 mmol) of 1M sodium
bistrimethylsilylamide in THF. The mixture was stirred at about -78°C for about 1.5 h
and then poured into 750 ml_ of ethyl acetate. The mixture was washed twice with
brine, dried over MgSO4 and concentrated to give a yellow oil. The oil was stirred in
150 ml of hexane overnight and the precipitated solid was then collected by filtration
to give 3.2 g of 5A as a white solid.
B. 5(S).6(R)-Diphenyl-3(R)-(3-phenyl-allyl)-morpholin-2-one
To 2.97 g (6.33 mmol) of 5A was added 20 ml of trifluoroacetic acid at about 0°C
and the mixture was stirred for about 2 h and then concentrated. The residue was
dissolved in water and basified with aqueous NaOH until a pH of 10 was maintained.
The mixture was extracted three times with ethyl acetate and the combined organic
extracts were washed with brine, dried over MgSO4 and concentrated to give an
orange oil which was purified by silica gel chromatography (10:90 v/v ethyl
acetate:hexane) to give 880 mg of SB as a white solid.
C. 2-(R)-Amino-5-phenyl-pentanoicacid
A mixture of 440 mg (1.19 mmol) of SB and 120 mg of palladium chloride in 20 ml of
ethanol and 10 mL of THF was hydrogenated at 45 psi. for about 16 h. The mixture
was filtered through diatomaceous earth and concentrated, and the residue was
triturated with ether to give 240 mg of 5C as a white solid.
D. 2-tert-Butoxycarbonylamino-2-methyl-propionic acid 2.5-dioxo-pyrrolidin-1-yl
ester
To a slurry of 5.0 g (24.6 mmol) of N-t-BOC-a-methylalanine in 13.5 mL of
methylene chloride was added 3.40 g (29.6 mmol) of N-hydroxysuccinimide and 5.65
g (29.6 mmol) of EDC. The slurry was stirred for about 17 h at room temperature.
The mixture was diluted with ethyl acetate and washed twice each with water,
saturated sodium bicarbonate solution and brine. Dried over MgSO4 and
concentrated. The product was purified by silica gel chromatography (1:1 v/v ethyl
acetate:hexanes) to give 5.2 g of the title compound of this part D as a white solid.
E. mV2-f2-tert-Butoxycarbonylamino-2-methyl-propionylamino)-5-phenylpentanoic
A mixture of 203 mg (1.05 mmol) of 5D, 378 mg (1.26 mmol) of 5C and 434 mg (3.36
mmol) of diisopropylethylamine in 2 mL of DMF was stirred over-night. The mixture
was diluted with ethyl acetate and extracted twice with 1N HCI. The aqueous phase
was extracted once with ethyl acetate. The pooled organic extracts were washed
three times with water and once with brine. The mixture was dried over MgSO4 and
concentrated. The residue was purified by silica gel chromatography using 80%
chloroform in hexane followed by 100% chloroform followed by 10% methanol in
chloroform to give 127 mg of 5E.
F. {1-[1-(3a-(R.S)-Benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahvdro-pyrazolo[4.3-
c]pyridine-5-cqrbonyl)-4-phenyl-(R)-butylcarbamoy I]-1 -methyl-ethyl}-carbam ic acid
tert-butyl ester
According to the method outlined in General Procedure A, 130 mg (0.53 mmol) of 3C
and 200 mg (0.53 mmol) of 5E were coupled to give a mixture of diastereomers.
The residue was purified by silica gel chromatography using an elution gradient of
(1:1 v/v ethyl acetate:hexane) to 100% ethyl acetate to give 40 mg of less polar 5F
isomer 1 and 40 mg of more polar 5F isomer 2. MS (Cl, NHa) 604 (MH+) for both
isomers.
G. 2-Amino-N-[1-(3a-fR)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyra2olo[
4.3-c]pyridine-5-carbonyl)-4-phenyl-(R)-butyl]-isobutyramide hydrochloride
To 40 mg (0.07 mmol) of 5F isomer 1 in 10 mL of ethanol was added 4 mL of
concentrated HCI and the mixture was stirred at room temperature for about 4 h.
The mixture was concentrated and the residue was precipitated from methylene
chloride/hexane and dried under vacuum to give 30 mg of 5G isomer 1. MS (Cl,
NH3) 504 (MH+). 1HNMR (CDaOD): (partial) 5 7.19 (m, 10 H), 4.37 (m, 1 H), 3.02
(m, 6 H), 2.67 (m, 4 H), 1.83 (m, 4 H), 1.62 (s, 6 H), 1.28 (m, 1 H).
H. 2-Amino-N-[1-(3a-(S)-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4,3-c]pyridine-5-carbonyl)-4-phenyl-(R)-butyl]-isobutyramide hydrochloride
To 40 mg (0.07 mmol) of 5F isomer 2 in 10 ml of ethanol was added 4 mL of
concentrated HCI and the mixture was stirred at room temperature for about 4 h.
The mixture was concentrated and the residue was precipitated from methylene
chloride/hexane and dried under vacuum to give 30 mg of 5H isomer 2. MS (Cl,
NHa) 504 (MH+). 1HNMR (CDaOD): (partial) 7.25 (m, 9 H), 6.88 (m, 1 H), 3.04 (s, 3
H), 2,71 (m, 4 H), 2.48 (m, 2 H), 1.75 (m, 4 H), 1.62 (m, 6 H), 1.28 (m, 1 H).
Example 6
2-Amino-N-[2-(3a-fR.S^-benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
A. {1-[2-f3a-rR.SWBenzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 200 mg (0.82 mmol) of 3C
and 320 mg (0.82 mmol) of 1E were coupled to give a mixture of diastereomers.
The residue was purified by silica gel chromatography using an elution gradient of
(1:1 v/v ethyl acetate:hexane) to 10% methanol in ethyl acetate to give 170 mg of
B. 2-Amino-N-[2-(3a-m.SVbenzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4r3-q]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
hydrochloride
To 170 mg (0.28 mmol) of 6A in 20 ml of ethanol was added 5 ml of concentrated
HCI and the mixture was stirred at room temperature for about 2.5 h. The mixture
was concentrated and the residue was precipitated from ethanol/hexane to give 70
mg of 68. MS (Cl, NH3) 506 (MH+). 1HNMR (CDaOD): 5 7.32 (m, 5 H); 7.16 (m, 5
H), 5.22 (m, 1 H), 4.67 (m,1 H), 4.55 (m, 2 H), 3.79 m, 2 H), 3.12 (m, 2 H), 3.00 (m,
2-Amino-N-[2-(3a-benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yi)-1-(1H-indol-3-ylmethyl)-2-oxo-ethyl]-isobutyramide hydrochloride
A. 3a-(R.S)-Benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridine-5-carboxylic acid tert-butyl ester
To 555 mg (1.60 mmol) of 38 in 27 mL of ethanol was added 240 mg (1.60 mmol) of
ethylhydrazineoxalate and the mixture was heated at reflux for about 4 h. The
mixture was concentrated and the residue was purified by silica gel chromatography
using an elution gradient of (10:1 v/v hexane:ethyl acetate) to (3:7 v/v hexane:ethyl
acetate) to give 357 mg of 7A. MS (Cl, NHa) 358 (MH+).
B. 3a-(R.S)-Benzyl-2-ethyl-2,3a,4.5,6.7-hexahydro-pyrazolo[4,3-c]pyridin-3-one
To 350 mg (0.98 mmol) of 7A in 3 mL of ethanol was added 1.5 ml of concentrated
HCI and the mixture was stirred at room temperature for about 2 h. The mixture was
concentrated to give 257 mg of 7B. MS (Cl, NHa) 258 (MH+).
C. {1-[2-(3a-(R.S)-Benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yl)-1 -(R)-(1 H-indol-3-ylmethyl)-2-oxo-ethylcarbamoyl]-1 -methyl-ethyl}-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 82 mg (0.28 mmol) of 7B
and 100 mg (0.26 mmol) of 2C were coupled and the residue was purified by silica
gel chromatography using an elution gradient of 100% methylene chloride to 2%
methanol in methylene chloride to give 110 mg of 7C. MS (Cl, NH3) 629 (MH+).
D. 2-Amino-N-[2-(3a-(R.S)-benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-c]pyridin-5-ylW1-mH1H-indol-3-ylmethyn-2-oxo-ethyl]-isobutyramide
hydrochloride
To 100 mg (0.15 mmol) of 7C in 2 mL of ethanol was added 1 mL of concentrated
HCI and the mixture was stirred at room temperature for about 2 h. The mixture was
concentrated to give 72 mg of 7D as a colorless foam. MS (Cl, NHa) 529 (MH+).
2-Amino-N-[3-(3a-(R)-benzyl-2-ethyl-3-oxo-2,3,3ar4.6.7-hexahydro-pyrazolo[4,3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride and
2-Amino-N-[2;-(3a-(S)-benzyl-2-ethyl-3-oxo-2.3.3ar4.6.7-hexahydro-pyrazolo[4f3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
A. {1-[2-(3a-Benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridin-
5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-carbamic acid
tert-butyl ester
According to the method outlined in General Procedure A, 85 mg (0.29 mmol) of 7B
and 100 mg (0.26 mmol) of 1E were coupled to give a mixture of diastereomers.
The residue was purified by silica gel chromatography using an elution gradient of
100% methylene chloride to 2% methanol in methylene chloride to give 6 mg of less
polar 8A isomer 1 and 11 mg of more polar 8A isomer 2. MS (Cl, NHa) 620 (MH+)
for both isomers.
B. 2-Amino-N-[2-(3a-(RVbenzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-q]pyridin-5-yl)-1-(RVbenzyloxymethyl-2-oxo-ethyl]-isobutyramide
To 5.7 mg (0.009 mmol) of 8A isomer 1 in 1 ml of ethanol was added 0.4 ml of
concentrated HCI and the mixture was stirred at room temperature for about 3 h.
The mixture was concentrated to give 4.7 mg of 8B isomer 1. MS (Cl, NHs) 520
(MH+). 1HNMR (CDsOD): (partial) 8 7.41 - 7.05 (m, 10 H), 5.20 (m, 1 H), 4.61 (m,
1H), 4.52 (s, 2 H). 3.71 (m, 1 H), 3.60 (m, 1 H), 2.61 (m, 3 H), 1.39 (m, 9 H).
C. 2-Amino-N-[2-(3a-(S)-benzyl-2-ethyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4r3-c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
hydrochloride
To 10 mg (0.016 mmol) of 8A isomer 2 in 1 ml of ethanol was added 0.4 ml of
concentrated HCI and the mixture was stirred at room temperature for about 3 h.
The mixture was concentrated to give 8 mg of 8C isomer 2. MS (Cl, NHs) 520
(MH+). 1HNMR (CDsOD): (partial) 8 7.43 - 7.00 (m, 10 H), 6.81 (m, 1 H), 5.32 (m, 1
H), 4.63 (m, 2 H), 4.53 (m, 1 H), 3.72 (m, 1 H), 1.37 (m, 9 H).
2-AminQ-N-f22-benzvl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridin-5-yn-1-
(R)-benzyloxyfnethyl-2-oxo-ethyl]-isobutyramide hydrochloride
A. 2-Benzyl-3-hydroxy-2.4.6.7-tetrahydro-pyrazolo[4.3-c]pyridine-5-carboxylic
acid tert-butyl ester
A mixture of 800 mg (3.11 mmol) of 3B and 495 mg (3.11 mmol) of benzylhydrazine
dihydrochloride and 423 mg (3.11 mmol) of sodium acetate trihydrate in 15 mL of
ethanol was heated at reflux for about 17 h. The mixture was concentrated and the
residue was dissolved in 100 ml of toluene and heated at reflux for about 48 h. The
mixture was diluted with ethyl acetate and washed with brine, dried over MgSO4 and
concentrated and the residue was purified by silica gel chromatography using 100%
ethyl acetate followed by 5% methanol in methylene chloride to give 530 mg of 9A
as a light brown solid. MS (Cl, NHa) 330 (MH+).
B. 2-Benzyl-4,5,6.7-tetrahydro-2H-pyrazolo[4.3-c]pyridin-3-ol
To 411 mg (1.24 mmol) of 3E in 30 mL of ethanol was added 10 mL of concentrated
HCI and the mixture was stirred at room temperature for about 30 min. The mixture
was concentrated and the residue was crystallized from methanol/ethyl acetate to
give 353 mg of 9B. MS (Cl, NHa) 230 (MH+).
C. {1-[2-(2rBenzyl-3-hydroxy-2.4.6.7-tetrahydro-pyrazolo[4,3-c]pyridin-5-yl)-1-Rbenzyloxymeth|
yl-2-oxo-ethylcarbamoyl]-1 -methyl-ethyl}-carbamic acid tert-butyl
According to the method outlined in General Procedure A, 100 mg (0.38 mmol) of 9B
and 145 mg (0.38 mmol) of 1E were coupled and the residue was purified by silica
gel chromatography (95:5 v/v methanol:methylene chloride) to give 42 mg of 9C as a
white solid. MS (Cl, NHa) 592 (MH+).
D. 2-AminQ-N-[2-r2-benzyl-3-Qxo-2.3.3a.4.6.7-hexahvdro-Dvrazolof4.3-clDvridin-
5-y|)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
To 42 mg (0.07 mmol) of 9D in 20 mL of ethanol was added 6 mL of concentrated
HCI and the mixture was stirred at room temperature for about 30 min. The mixture
was diluted with ethanol concentrated and the residue was precipitated from
methanol/ethyl acetate to give 35 mg of 9D as a white solid. MS (Cl, NHs) 492
(MH+). 1HNMR (CDaOD): (partial) 7.41 - 7.16 (m, 10 H), 5.19 (m, 3 H), 4.48 (m, 4
H), 3.88 (m, 1 H), 3.74 (m, 2 H), 2.68 (m, 2 H), 1.58 (m, 6 H).
Example 10
2-Amino-N-{2-[3a-(R)-benzyl-3-oxo-2-(2r2,2-trifluoro-ethyl)-2.3.3a.4.6f7-hexahydropyra2olo[
4.3-p]pyridin-5-yl]-1-(RVbenzyloxymethyl-2-oxo-ethyl-isobutyramide
hydrochloride and
2-Amino-N-{2-[3a-fSVbenzyl-3-oxo-2-r2.2.2-trifluoro-ethyn-2.3.3a.4.6.7-hexahydropyrazolQ[
4,3-;Jpyridin-5-yl]-1-(R)-benzyloxymethyl-2-oxo-ethyl}-isobutyramide
hydrochloride
A. 3a-(R,S)-Benzyl-3-oxo-2-(2,2f2-trifluoro-ethyl)-2.3,3a.4.6,7-hexahydropyrazolo[
4,3-q]pyridine-5-carboxylic acid tert-butyl ester
A mixture of 840 mg (2.42 mmol) of 3B and 276 mg (2.42 mmol) of 2,2,2-
trifluoroethylhydrazine (70% in water) in 20 ml of ethanol was heated at reflux for
about 5 h and then concentrated. The residue was dissolved in 40 mL of toluene
and heated at reflux for about 17 h. The mixture was concentrated and the residue
was purified by silica gel chromatography (9:1 v/v hexane:ethyl acetate) to give 703
mg of 10A as a yellow oil. MS (Cl, NHs) 412 (MH+).
B. 3a-(R.3)-Benzy|-2-(2.2.2-trifluorQ-ethyl)-2.3a.4.5.6.7-hexahydrQ-pyrazQlQ[4.3-
c]pyridin-3-one
To 600 mg (1.46 mmol) of 10A at about 0 °C was added 3 mL of cold trifluoroacetic
acid and the mixture was stirred for about 3 h, allowing the solution to reach room
temperature as it did so. The mixture was concentrated and the residue was
dissolved in water and the solution was basified to pH 11 with 5N NaOH and then
saturated with potassium carbonate. The solution was extracted three times with
ethyl acetate and the combined organic extracts were washed with brine, dried over
MgSO4 and concentrated to give 345 mg of 10B as an opaque oil. MS (Cl, NHa)
312(MH+).
C. (1-{2-[3aR.S)-Benzyl-3-oxQ-2-2.2.2-trifluoro-ethyl)-2.3.3a.4.6.7-hexahydropyrazolQ[
4.3-c)pyridin-5-vl]-1-(RVbenzvloxymethvl-2-oxo-ethvlcarbamovl}-1-methvlethyl)-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 137 mg (0.44 mmol) of
10B and 167 mg (0.44 mmol) of 1E were coupled to give a mixture of diastereomers.
The residue was purified by silica gel chromatography using an elution gradient
100% methylene chloride to 5% methanol in methylene chloride to give 128 mg of
less polar 10C isomer 1 and 63 mg of more polar 10C isomer 2. MS (Cl, NH3) 674
(MH+) for both isomers
D. 2-Ammo-N-{2-[3a-(R)-benzyl-3-oxo-2-(2.2.2-trifluoro-ethvn-2.3.3a.4.6.7-
hexahydro-pyrazolo[4.3-c]pyridin-5-yl]-1-(R)-benzyloxymethyl-2-oxo-ethyl}-
isobutyramide hydrochloride
To 120 mg (0.18 mmol) of 10C isomer 1 in 3.5 ml of ethanol was added 1.5 mL of
concentrated HCI and the mixture was stirred at room temperature for about 2 h.
The mixture was concentrated to give 94 mg of 10D isomer 1 as an off-white
powder. MS (Cl, NHs) 574 (MH+). 1HNMR (CDsOD): (partial) 5 7.31 (m, 5 H), 7.18
(m, 5 H), 5.21 (m, 1 H), 4.57 (m, 3 H), 4.26 (m, 1 H), 4.08 (m, 1 H), 3.79 (m, 2 H),
3.09 (m, 4 H), 2.65 (m, 2 H), 1.63 (m, 6 H).
E. 2-Amipo-N-{2-[3a-(S)-benzyl-3-oxo-2-(2.2.2-trifluoro-ethyn-2.3.3a.4.6.7-
hexahydro-pyrazolo[4.3-c]pyridin-5-yl]-1-(R)-benzyloxymethyl-2-oxo-ethyl}-
isobutyramide hydrochloride
To 53 mg (0.079 mmol) of 10C isomer 2 in 3.5 mL of ethanol was added 1.5 mL of
concentrated HCI and the mixture was stirred at room temperature for about 2 h.
The mixture was concentrated to give 41 mg of 10E isomer 2 as a light yellow solid.
MS (Cl, NHs) 574 (MH+). 1HNMR (CD^OD): (partial) 8 7.33 (m, 5 H), 7.15 (m, 4 H),
6.81 (m, 1 H), 5.30 (m, 1 H), 4.67 (m, 4 H), 4.15 (m, 2 H), 3.77 (m, 2 H), 3.09 (m, 3
H), 2.64 (m, 3 H), 1.58 (m, 6 H).
Example 11
2-Amino-N-[2^3a-fRVbenzyl-2-tert-butvl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolQ[4.3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide methanesulfonate
and
2-Amino-N-[2-(3a-(S)-benzyl-2-tert-butyl-3-oxo-2.3.3a,4.6,7-hexahydro-pyrazolo[4r3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide methanesulfonate
A. 3a-(R.S)-Benzyl-2-tert-butyl-3-oxo-2.3.3a.4.6.7-hexahydrQ-pyrazolo[4.3-
c]pyridine-5-cgrboxylic acid tert-butyl ester
To 2.07 g (5.95 mmol) of 14B in 40 mL of ethanol was added 0.97 g (7.7 mmol) of
tert-butylhydrazine hydrochloride and 0.63 g (7.7 mmol) of sodium acetate and the
ixture was heated at about 70 °C for about 17 h. The mixture was cooled and the
solution decanted from the precipitate and concentrated. The residue was dissolved
in 80 ml of toluene and heated at reflux for about 6 h. The mixture was
concentrated and the residue was purified by silica gel chromatography (9:1 v/v
hexane:ethyl acetate) to give 1.7 g of 11 A. MS (Cl, NHa) 386 (MH+).
B. 3a-(R.S)-Benzyl-2-tert-butyl-2.3a.4.5.6.7-hexahydro-pyrazolo[4.3-c]pyridin-3-
one
To 535 mg (1.39 mmol) of 11A in 20 ml of methylene chloride was added 225 jaL of
methanesulfonic acid and the mixture was stirred for about 1.5 h at room
temperature. The mixture was diluted with ethyl acetate and washed twice with 1N
NaOH and once with brine, dried over Na2SO4 and concentrated to give 246 mg of
11B. MS (Cl, NH3) 286 (MH+).
C. {1-[2-(3a-(R.S)-Benzyl-2-tert-butyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-c]pyridin-5-yh-1-(R)-benzvloxvmethyl-2-oxo-ethylcarbamoyl]-1-methylethyl}-
carbamic acid tert-butyl ester
According to the method outlined in General Procedure A, 246 mg (0.86 mmol) of
11B and 328 mg of 14F were coupled to give a mixture of diastereomers. The
residue was purified by silica gel chromatography (6:4 v/v hexane/ethyl acetate) to
give 250 mg of less polar 11C isomer 1 and 90 mg more polar 11C isomer 2. MS
(Cl, NH3) 648 (MH+) for both isomers.
D. 2-Amino-N-[2-(3a-(R)-benzyl-2-tert-butyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-clpyridin-5-vh-1-fR)-benzyloxymethvl-2-oxo-ethvl]-isobutyramide
methanesulfonate
To 210 mg (0.32 mmol) of 11C isomer 1 in 15 mL of methylene chloride at about 0
°C was added 28 nL (0.44 mmol) of methanesulfonic acid. The ice bath was
removed and the mixture was stirred for about 3 h, diluted with 15 ml of diethyl ether
and the precipitated solid was collected by filtration to give 100 mg of 110 isomer 1.
MS (Cl, NHs) 548 (MH+). 1H NMR (CDsOD): (partial) 6 7.33 (m, 5 H), 7.27 - 7.07
(m, 5 H), 5.21 (m, 1 H), 4.54 (m, 3 H), 3.86 (m, 3 H), 3.10 (m, 4 H), 2.61 (s, 3 H),
1.62 (m, 6 H), 1.18(s, 9 H).
E. 2-Amino-N-[2-r3a-(SVbenzyl-2-tert-butyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazQlo[
4.3-q]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide
methanesulfonate
To 85 mg (0.13 mmol) of 11C isomer 2 in 10 mL of methylene chloride at about 0
°C was added 21 ^L (0.32 mmol) of methanesulfonic acid. The ice bath was
removed and the mixture was stirred for about 3 h, diluted with 20 mL of diethyl ether
and the precipitated solid was collected by filtration to give 46 mg of 11E isomer 2.
MS (Cl, NH3) 548 (MH+). 1H NMR (CDsOD): (partial) 8 8.28 (br d, 1 H), 7.32 (m, 5
H), 7.18 (m, 4 H), 6.84 (m, 1 H), 5.31 (m, 1 H), 4.60 (m, 3 H). 3.70 (m, 3 H), 3.18 -
2.92 (m, 3 H), 2.68 (s, 3 H), 1.57 (m, 6 H), 1.13 (s, 9 H).
Example 12
2-Amino-N-[1-(R)-(1H-indol-3-ylmethyl)-2-/2-methyl-3-oxo-3a-m.S)-pyridin-2-
ylmethyl-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-
isobutyramide dihydrochloride
A. 4-Oxo-3-(R.S)-pyridin-2-ylmethyl-piperidine-1.3-dicarboxylic acid 1-tertbutyl
ester 3-methyl ester
To a solution of 2.00 g (7.8 mmol) of 3A in 32 ml of THF was added 468 mg (11.7
mmol) of sodium hydride (60% oil dispersion) at about 0 °C and the mixture was
stirred for about 30 min. A solution of 762 mg (6.0 mmol) 2-picolyl chloride in 5 ml
of THF was added to the stirring solution over about 5 min, followed by the addition
of 432 mg (2.6 mmol) of potassium iodide. The ice bath was removed and the
mixture was heated for about 17 h at reflux. The mixture was diluted with ethyl
acetate and washed once with water and once with brine, dried over MgSO4, and
concentrated. The residue was purified by silica gel chromatography using (6:4 v/v
etherhexane) followed by (6:4 v/v ethyl acetate:hexane) to give 1.2 g of 12A. MS
(Cl, NH3) 349 (MH+).
B. 2-Methyl-3-oxo-3a-(R,S)-pyridin-2-ylmethyl-2.3r3a.4.6,7-hexahydropyrazolo[
4.3-c]pyridine-5-carboxylic acid tert-butyl ester
A mixture of 1.20 g (3.45 mmol) of 12A and 159 mg (3.45 mmol) of methylhydrazine
in 20 mL of ethanol was heated at reflux for about 6.5 h. The mixture was
concentrated and the residue was dissolved in 25 mL toluene and heated at reflux
for about 17 h. The mixture was concentrated and the residue was purified by silica
gel chromatography (65:35 v/v ethyl acetate:hexane) to give 450 mg of 12B. MS
(Cl, NH3) 345 (MH+).
C. 2-Methyl-3a-(R.SVpyridin-2-ylmethyl-2.3a.4.5.6.7-hexahvdro-pyrazolQ[4.3-
c]pyridin-3-one dihydrochloride
A mixture of 450 mg (1.30 mmol) of 12B in 2 mL of 4M HCI/dioxane was stirred at
room temperature for about 4.5 h. The mixture was concentrated to give 450 mg of
12C. MS (Cl, NH3) 245 (MH+).
D. {1-[1-f1-(R)-H-lndol-3-vlmethyn-2-(2-methyl-3-oxo-3a-(R.S)-pyridin-2-
ylmethyl-2.3,3a.4.6t7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-2-oxo-ethylcarbamoyl]-
1 -methyl-ethy According to General Procedure A, 108 mg (0.31 mmol) of 12C and 122 mg (0.31
mmol) of 2C were coupled and the residue was purified by silica gel chromatography
(95:5 v/v ethyl acetate:methanol) to give 118 mg of 12D. MS (Cl, NHa) 616 (MH+).
E. 2-Amino-N-[1-(RV(1H-indol-3-ylmethylV2-(2-methyl-3-oxo-3a-(R.S)-pyridin-2-
ylmethyl-2.3.3a.4.6r7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-
isobutyramide dihydrochloride
A mixture of 110 mg (0.18 mmol) of 12D in 1 mL of 4M HCI/dioxane was stirred at
room temperature for 17 h. The mixture was concentrated to give 51 mg of 12E.
MS (Cl, NH3) 516 (MH+). 1HNMR (CDaOD): (partial) 5 8.91 - 8.52 (m, 2 H), 8.04 (m,
2 H), 7.76 - 7.50 (m, 3 H), 6.82 (m. 1 H), 4.62 (m, 1 H), 3.36 (s, 3 H), 1.63 (s, 6 H).
Example 13
2-Amino-N-[1-(R)-benzyloxymethyl-2-(2-methyl-3-oxo-3a-(R,S)-pyridin-2-ylmethyl-
2,3.3a,4,6.7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-isobutyramide
dihydrochloride
A. {1-[1-(R-Benzyloxymethyl-2-(2-methyl-3-oxo-3aWR.SVpyridin-2-ylmethylethyl}-
carbamic acid tert-butyl ester
According to General Procedure A, 86 mg (0.27 mmol) of 12C and 103 mg (0.27
mmol) of 1E were coupled and the residue was purified by silica gel chromatography
(95:5 v/v ethyl acetate:hexane) to give 82 mg of 13A.
B. 2-Amino-N-[1-(RVbenzvloxymethyl-2-(2-methyl-3-oxo-3a-(R.S-pvridin-2-
ylmethyl-2.3.3a.4,6.7-hexahydro-pyrazolo[4,3-c]pyridin-5-yl)-2-oxo-ethyl]-
IsQbutvramide dihvdrochloride
A mixture of 75 mg (0.12 mmol) of 13A in 1 mL of 4M HCI/dioxane was stirred at
room temperature for about 17 h. The mixture was concentrated to give 80 mg of
13B. MS (Cl, NH3) 507 (MH+). 1HNMR (CDaOD): (partial) 5 8.78 (m, 1 H), 8.46 (m,
1 H), 8.13 - 7.82 (m, 2 H), 7.32 (m, 5 H), 4.57 (m, 3 H), 3.96 (m, 1 H), 3.82 (m, 2 H),
2-Amino-N-[2-(3a-(R)-benzyl-2-methyl-3-oxo-2.3.3a,4.6.7-hexahydro-pyrazolo[4r3-
To a mixture of 100.0 g (516.4 mmol) of 4-oxo-piperidine-3-carboxylic acid methyl
ester and 63 g (516.4 mmol) of 4,4-dimethylaminopyridine in 1 L of methylene
chloride at about 0 °C was added a solution of 113.0 g (516.4 mmol) of di-tertbutyldicarbonate
in 100 ml of methylene chloride over about 90 min. The mixture
was slowly warmed to room temperature and then stirred for about 19 h. The
mixture was washed three times each with 10% aqueous HCI, saturated aqueous
sodium bicarbonate solution and brine, dried over MgSO4 and concentrated to give
130.5 g of 14A as an amorphous solid. 1HNMR (CDCIa): 8 4.03 (br, 2H); 3.74 (s,
3H), 3.56 (t, 2H), 2.36 (t, 2H), 1.42 (s, 9H).
B. 3-(R)-Benzyl-4-oxo-piperidine-1.3-dicarboxylic acid 1-tert-butyl ester 3-methy|
To a stirred suspension of 11.7 g (293 mmol) of sodium hydride (60% oil dispersion
washed twice with 100 mL of hexane) in 100 mL of DMF was added a solution of
65.4 g (254 mmol) of 14A in 150 mL of DMF at about 0 °C over about 45 min. The
ice bath was removed and the mixture was stirred at room temperature for about 45
min. The mixture was recooled to about 0 °C and 35.2 mL (296 mmol) of
benzylbromide in 200 mL of DMF was added dropwise to the stirring solution and the
mixture was stirred for about 23 h at room temperature. To the solution was
carefully added 550 mL of water and the mixture was stirred for about 30 min. The
mixture was extracted three times with ethyl acetate and the combined organic
extracts were washed five times with water, once with brine, dried over MgSO4 and
concentrated to give 98 g of a yellow oil. The oil was crystallized from hexane to
give 71 g of 14B as a white solid. MS (Cl, NHs) 348 (MH+). 1HNMR (CDCIa):
(partial) 6 7.23 (m, 3 H), 7.13 (m, 2 H), 4.58 (br m, 1 H), 4.18 (br, 1 H), 3.63 (s, 3 H),
3.28 - 2.96 (m, 4 H), 2.72 (m, 1 H), 2.43 (m, 1 H), 1.44 (s, 9 H).
C. 3a-(R)-Benzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridine-5-carboxylic acid tert-butyl ester
A mixture of 47.0 g (135 mmol) of 14B, 38.9 g (270 mmol) of methylhydrazine sulfate
and 44.3 g (540 mmol) of sodium acetate in 900 mL of ethanol was heated at reflux
for about 17 h under nitrogen. The mixture was concentrated and the residue was
dissolved in ethyl acetate and washed three times with water and once with brine,
dried over MgSO4 and concentrated to give a yellow oil. The oil was stirred in 750
ml of hexane for about 3 h to give 41.17 g of 14C as a white solid. MS (Cl, NHa)
344 (MH+). 1HNMR (CDCIs): (partial)8 7.19 (m, 3 H), 7.05 (m, 2 H), 4.61 (br m, 2
H), 3.24 (m, 1 H), 3.09 (s, 3 H), 3.01 (m, 1 H), 2.62 (m, 4 H), 1.52 (s, 9 H).
D. 3a-fR.S)-Benzyl-2-methyl-2.3a.4.5.6.7-hexahydro-pyrazolo[4.3-c]pyridin-3-
one hydrochloride
Anhydrous HCI was bubbled through a solution of 24.55 g (71.5 mmol) of 14C in 800
ml of diethyl ether at about 0 °C for about 12 min. The mixture was stirred for about
3 h, during which time a white precipitate formed. The precipitated solid was
collected by filtration and to give 19.2 g of 14D. MS (Cl, NHs) 244 (MH+). 1HNMR
(CD3OD): (partial) 5 7.25 (m, 3 H), 7.05 (m, 2 H), 3.77 (m, 2 H), 3.51 (d, 1 H), 3.25
(m, 1 H), 3.17 (m, 3 H), 3.03 (s, 3 H), 2.81 (m, 1 H).
E. 2-tert-Butoxycarbonylamino-2-methyl-propionic acid 2,5-dioxo-pyrrolidin-1-yl ester
To a stirring solution of 100.0 g (492 mmol) of Boc-a-methylalanine and 94.O g (492
mmol) of EDC in 2 L of methylene chloride at about 0 °C was added 56.63 g (492
mmol) of N-hydroxysuccinimide in portions and the reaction was then allowed to
warm to room temperature. The mixture was stirred for about 24 h and washed
twice each with saturated aqueous sodium bicarbonate solution and brine, dried over
Na2SO4 and concentrated to give 124.0 g of 14E as a white solid. 1HNMR (CDCIs):
5 4.96 (br, 1H), 2.82 (s, 4H), 1.66 (s, 6H), 1.48 (s, 9H).
F. 3-fR)-Benzyloxy-2-(2-tert-butoxycarbonylamino-2-methyl-propionylamino)-
propionic acid
A mixture of 50.5 g (168 mmol) of 14E, 33.5 g (168 mmol) of O-benzyl-Dserine,
and 51.05 g (505 mmol) of triethy famine in 400 ml of dioxane and 100 ml of
water was heated at about 45 °C for about 16 h. The mixture was diluted with ethyl
acetate and acidified to pH 2 with acetic acid. The layers were separated and the
organic phase was washed with brine, dried over Na2SO4 and concentrated to give
650 g of 14F as a white solid. 1HNMR (CD3OD): (partial) 8 7.55 (d, 1 H), 7.29 (m, 5
H), 4.52 (m, 1 H), 4.48 (s, 2 H), 3.84 (d of d, 1 H), 3.69 (d of d, 1 H), 1.42 (s, 6 H),
1.38(s, 9H).
RBengy2!-methyl2.-3aA5.6.7--hexahydro-pyrazolQ[4.3-G]pyridin-3-on&
To a mixture of 5,00 g (20.6 mmol) of the free base of 14D and 3.09 g (20.6 mmol) of
L-tartaric acid in 80 rnl_ of acetone and 3.2 ml of water was heated under nitrogen at
about 70 °C for about 70 h, during which time the reaction mixture became a thick
suspension and an additional 20 ml of acetone was added. The reaction mixture
was cooled slowly to room temperature and then filtered. The solid that was
collected was washed with acetone and dried under vacuum to give 7.03 g of 14G as
H. 3a-(R)-Bepzyl-2-methyl-2,3a,4,5.6.7-hexahydro-pyrazolo[4.3-c]pyridin-3-one
To a suspension of 5.00 g (12.7 mmol) of 14G in 80 mL of methylene chloride at
about 0 °C was added 1.72 ml (25.4 mmol) of ammonium hydroxide and the mixture
was stirred for about 1 5 min. The cold solution was filtered and used immediately in
A mixture of 4.83 g (12.7 mmol) of 14F, the solution from 14f/; 2.60 g (19.1 mmol) of
HOAT, and 2.45 g (12.8 mmol) of EDC was stirred at about 0 °C under nitrogen for
about 1 h and then warmed to room temperature and stirred for about 16 h. The
mixture was filtered and the filtrate was washed with saturated aqueous sodium
bicarbonate and water, dried over MgSO4 and concentrated to give 7.35 g of 141 as
J- 2-Amino-N-[2-(3a-(R)-ben2yl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-c]pyridin-5-vn-1-(RH benzy&yy 0 Zj -2-oxo-ethvl]-isobutyramide
To 755 mg (1.25 mmol) of 141 in 7 ml of methylene chloride at about 0 °C was
added 3.5 ml of cold trifluoroacetic acid and the mixture was stirred for about 1 h at
about 0 °C. The mixture was allowed to warm to room temperature and stirred for
about 2 h. The mixture was concentrated and co-evaporated twice with toluene.
The residue was dissolved in chloroform and washed twice with saturated aqueous
sodium bicarbonate and once each with water and brine. The mixture was dried
over MgSO4 and concentrated to give 594 mg of 14J as an oil.
2-Amino-N-[1m-benzyloxvmethyl-2-(2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4.3-c]pyridin-5-vn-2-oxo-ethvl]-isobutyramidehydrochloride
A. 2-Methyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolQ[4.3-c]pyridine-5-carboxylic acid
A mixture of 3.00 g (11.66 mmol) of 3A and 537 mg (11.66 mmol) of
methylhydrazine in 100 ml_ of ethanol was heated at reflux for about 17 h. The
mixture was concentrated and the residue was dissolved in 100 mL toluene and
heated at reflux for about 17 h. The mixture was diluted with ethyl acetate, and
washed twice with brine, dried over MgSO4 and concentrated. The residue was
purified by silica gel chromatography using an elution gradient of 100% ethyl acetate
to 5% methanol in methylene chloride to give 2.28 g of 15A as a white solid. 1HNMR
(CD30D): 8 4.20 (s, 2H), 3.67 (t, 2H), 3.43 (s, 3H), 2.58 (t, 2H), 1.48 (s, 9H).
B. 2-Methyl-2.3a.4.5.6.7-hexahydro-pyrazolo[4.3-c]pvridin-3-onehydrochloride
To 510 mg (2.01 mmol) of 15A in 30 ml of ethanol was added 10 mL of
concentrated HCI and the mixture was stirred at room temperature for about 35 min.
The mixture was concentrated and the residue was crystallized from methanol/ethyl
acetate to give 425 mg of 15B as a yellow solid. 1HNMR (CDaOD): 5 4.27 (S, 2H),
3.71 (S, 3H), 3,56 (T, 2H), 3.05 (T, 2H).
C. {1-[1-(R)-Benzyloxymethyl-2-f2-methyl-3-oxo-2.3.3a.4.6,7-hexahydropyrazolo[
4.3-c]pyridin-5-y»-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-carbamicacid tertbutyl
ester
According to the method outlined in General Procedure A, 100 mg (0.53 mmol) of
15B and 202 mg (0.53 mmol) of 1E were coupled and the residue was purified by
silica gel chromatography (95:5 v/v methylene chloride:methanol) to give 54 mg of
15C as a white solid. MS (Cl, NHs) 516 (MH+).
D. 2-Amino-N-[1-R-b6nzyloxymethyl-2-(2-methyl-3-oxo-2.3.3a.4.6.7-hexahydropyrazolo[
4,3-c3pyridin-5-yl)-2-oxo-ethyl]-isobutyramidehydrochloride
To 54 mg (0.10 mmol) of 15C in 30 ml of ethanol was added 10 ml of concentrated
HCI and the mixture was stirred at room temperature for about 40 min. The mixture
was concentrated and the residue was precipitated from methanol/ethyl acetate to
give 50 mg of 15D. MS (Cl, NHa) 416 (MH+). 1HNMR (CDaOD): (partial) 6 7.28 (m,
5 H), 5.18 (m 1 H), 4.69-4.38 (m, 4 H), 3.88 (m, 1 H), 3.73 (m, 2 H), 3.68 (s, 2 H),
3.61 (m, 1 H), 2.67 (m, 1 H), 1.57 (s, 6 H).
2-Amino-N-[2-(2-benzyl-3-oxo-2.3.3a.4.6.7-hexahvdro-pyrazolo[4.3-c]Dyridin-5-yn-
1 (R)-(1 H-indol-3-ylmethyl)-2-oxo-ethyl]-isobutyramide hydrochloride
A. 2-Benzyl-3-oxo-2.3r3a.4.6r7-hexahydro-pyrazolo[4.3-c]pyridine-5-carboxylic acid
A mixture of 800 mg (3.1 1 mmol) of 3A and 495 mg (3.1 1 mmol) of benzyl-hydrazine
dihydrochloride in 15 ml of ethanol was heated at reflux for about 17 h. The mixture
was concentrated and the residue was dissolved in 100 ml toluene and heated at
reflux for about 48 h. The mixture was diluted with ethyl acetate, and washed twice
with brine, dried over Na2SO4 and concentrated. The residue was purified by silica
gel chromatography using an elution gradient of 100% ethyl acetate to 5% methanol
in methylene chloride to give 530 mg of 16A as a tan solid. MS (Cl, NH3) 330
B. 2-Benzyl-2.3a.4.5.6.7-hexahydro-pvrazolo[4.3-c]pvridin-3-one hydrochloride
To 411 mg (1.24 mmol) of 16A in 30 mL of ethanol was added 10 mL of
concentrated HCI and the mixture was stirred at room temperature for about 30 min.
The mixture was concentrated and the residue was crystallized from methanol/ethyl
acetate to give 353 mg of 16B as a yellow solid. MS (Cl, NHa) 230 (MH+). 1HNMR
(CDsOD): 5 7.26-7.40 (m, 5H), 5.22 (s, 2H), 4.12 (s, 2H), 3.53 (t, 2H), 3.00 (t, 2H).
C. (R)-2-(2-tert-Butoxycarbonylamino-2-methyl-propionylamino)-3-(1H-indol-3-
To a stirring solution of 30.6 g (0.15 mol) of D-tryptophan, 30.4 g (0.30 mol) of Nmethylmorpholine
in 450 ml of (4:1) dioxane:water, was added 45.0 g (0.15 mol) of
14E and the mixture was stirred for about 72 h. Excess dioxane was removed by
evaporation and water and ethyl acetate were added to the mixture. The pH of the
solution was adjusted to 3 with concentrated HCI and the layers were separated.
The organic layer was washed with water and brine, dried over MgSO4 and
concentrated. The residue was crystallized from ethyl acetate/hexanes to give 37.0
g of an off-white solid.
D. (1-[2-(2-Benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolof4.3-c]pyridin-5-yn-1-
(R)-(1 H-indol-3-ylmethyl)-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-carbamic acid
According to the method outlined in General Procedure A, 100 mg (0.38 mmol) of
16B and 202 mg (0.53 mmol) of 16C were coupled and the residue was purified by
silica gel chromatography (95:5 v/v methylene chloride:methanol) to give 45 mg of
16D as a white solid. MS (Cl, NHs) 601 (MH+).
E. 2-Amino-N-[2-(2-benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridin-
5-yl)-1 -(R)-(1 H-indol-3-ylmethyl)-2-oxo-ethyl]-isobutyramide hydrochloride
To 45 mg (0.07 mmol) of 16D in 60 ml_ of ethanol was added 20 ml of concentrated
HCI and the mixture was stirred at room temperature for 35 min. The mixture was
concentrated and the residue was precipitated from methanol/ethyl acetate to give
30 mg of 16E. 1HNMR (CDaOD): (partial) 8 7.40 (m, 4 H), 7.25 (m, 3 H), 7.11 (m, 2
H), 6.96 (m, 2 H), 6.81 (m, 1 H), 5.38 - 4.93 (m, 3 H), 4.46 (m, 1 H), 4.22 (m, 1 H),
3.96 (m, 1 H), 3.69 (m, 1 H), 3.18 (m, 1 H), 2.28 (m, 1 H), 1.57 (m, 6 H),1.38 (m, 1
2-Amino-N-[1-benzyloxymethyl-2-(2,3a-dimethyl-3-oxo-2.3.3a.4r6.7-hexahydropyrazolo[
4.3-e]pyridin-5-yl)-2-oxo-ethyl]-isobutyramide hydrochlon'de
A. 3-Methyl-4-oxo-piperidine-1.3-dicarboxylic acid 1-tert-butyl ester 3-(R.S)-methyl
To a solution of 2.00 g (7.77 mmol) 3A in 30 mL of DMF was added 308 mg (7.77
mmol) of sodium hydride (60% oil dispersion) and the mixture was stirred at room
temperature for about 25 min. To the stirring solution was added 0.50 ml (7.77
mmol) of methyl iodide and the mixture was stirred for about 17 h at room
temperature. The mixture was diluted with ethyl acetate and washed once with
water and four times with brine, dried over MgSO4, and concentrated. The residue
was purified by silica gel chromatography (7:3 v/v hexane:ethyl acetate) to give 1.75
g of 17A as a clear oil. MS (Cl, NH3) 272 (MH+).
B. 2r3a-fR.S)-Dimethyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridine-5-
carboxylic acid tert-butyl ester
A mixture of 1.62 g (9.50 mmol) of 17A and 435 mg (9.50 mmol) of methylhydrazine
in 30 ml of ethanol was heated at reflux for about 4 h. The mixture was
concentrated and the residue was dissolved in 50 ml toluene and heated at reflux
for about 14 h. The mixture was diluted with ethyl acetate, and washed twice with
brine, dried over Na2SO4 and concentrated. The residue was purified by silica gel
chromatography (7:3 v/v hexane:ethyl acetate) to give 1.00 g of 17B as a white solid.
MS (Cl, NH3) 268 (MH+).
C. 2,3a-(R,S)-Pimethyl-2,3a,4,5,6,7-hexahydro-pyrazolo[4.3-c]pyridin-3-one
To 1.00 g (3.74 mmol) of 17B in 40 ml of ethanol was added 8 ml of concentrated
HCI and the mixture was stirred at room temperature for about 35 min. The mixture
was concentrated and the residue was crystallized from methanol/ethyl acetate to
give 850 mg of 17C as a white solid. MS (Cl, NH3) 168 (MH+).
D. {1-[1-(RVBenzvloxvmethvl-2-(2.3a-rR.S)-dimethyl-3^xo-2.3.3a.4.6.7-
hexahydro-pyrazolo[4.3-c]pyridin-5-yn-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-
carbamic acicf tert-butyl ester
According to the method outlined in General Procedure A. 150 mg (0.74 mmol) of
17C and 514 mg (1.35 mmol) of 1E were coupled and the residue was purified by
silica gel chromatography (85:15 v/v hexane:ethyl acetate) to give 185 mg of 17D as
a white solid.
E. 2-Amtno-N-[1-(R)-benzyloxymethyl-2-(2.3a-(R.S)-dimethyl-3-oxo-
2.3.3a,4.6,7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-isobutyramide
hydrochloride
To 173 mg (0.33 mmol) of 178 in 40 mL of ethanol was added 15 ml of
concentrated HCI and the mixture was stirred at room temperature for about 1 h.
The mixture was concentrated and the residue was diluted wrth chloroform and
washed with saturated aqueous sodium bicarbonate and brine, dried over Na2SO4
and the residue was purified by silica gel chromatography using an elution gradient
of 100% ethyl acetate to 10% diethylamine in ethyl acetate. The residue was
dissolved in ethanol and acidified with aqueous HCI. The mixture was concentrated
and the residue was crystallized from methanol/ethyl acetate to give 65 mg of 17E
a white solid. MS (Cl, NH3) 502 (MH+). 1HNMR (CDaOD): (partial) 8 7.32 (m, 5 H),
5.14 (m, 1 H), 4.53 (m, 3 H), 3.71 (m, 3 H), 2.97 (m, 1 H), 2.83 (m, 1 H), 2.57 (m, 1
H), 1.98 (m, 2 H), 1.61 (m, 6 H), 1.38 (s, 3 H).
Example 18
2-Amino-N-[2-(3a-(R)-benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c3pyridin-5-yiM-fR)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride and
2-Amino-N-[2-(3a-(S)-benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
A. 3-Benz;yl-4-oxo-piperidine-3-carboxylic acid methyl ester
To 200 mg (0,58 mmol) of 3B at about 0 °C was added 5 mL of cold trifluoroacetic
acid and the mixture was stirred for about 1 h. The mixture was concentrated and
the residue was co-evaporated with ethyl acetate and hexane. To the residue was
added 2N NaOH to make it basic and the mixture was extracted with chloroform.
The combined organic extracts were dried over MgSO4 and concentrated to give
18A in quantitative yield.
B. 3-(R.S)-Benzyl-1-[3-benzyloxy-2-fRW2-tert-butoxycarbonvlamino-2-methylpropionylamipo)-
propionyl]-4-oxo-piperidine-3-carboxylic acid methyl ester
According to the method outlined in General Procedure A, 1.77 g (7.16 mmol) of 18A
and 3.04 g (8.0 mmol) of 14F were coupled to give a mixture of diastereomers. The
residue was purified by silica gel chromatography (7:3 v/v hexaneiethyl acetate) to
give 820 mg of less polar 18B isomer 1 and 1.14 g more polar 18B isomer 2. MS
(Cl, NHa) 611 (MH+) for both isomers.
C. {1-[2-(3a-(R.S)-Benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-c]pyridin-
5-y|)-1-(R)-bqn2yloxymethyl-2-oxo-ethylcarbamoyl]-1-methyl-ethyl}-carbamic acid
tert-butyl ester
To a solution of 820 mg (1.32 mmol) of 18B isomer 1 in 13 ml of ethanol was added
342 mg (2.63 mmol) of hydrazine sulfate and 431 mg (5.26 mmol) of sodium acetate
and the mixture was heated at reflux for about 17 h. The mixture was concentrated
and the residue was diluted with ethyl acetate and washed with saturated aqueous
sodium bicarbonate and brine, dried over MgSO4 and concentrated. The residue
was purified by silica gel chromatography using an elution gradient of 75% ethyl
acetate in hexane to 100% ethyl acetate to give 550 mg of 18C isomer 1.
To a solution of 1.14 g (1.86 mmol) of 18B isomer 2 in 20 ml_ of ethanol was added
485 mg (3.73 mmol) of hydrazine sulfate and 613 mg (7.48 mmol) of sodium acetate
and the mixture was heated at reflux for about 17 h. The mixture was concentrated
and the residue was diluted with ethyl acetate and washed with saturated aqueous
sodium bicarbonate and brine, dried over MgSO4 and concentrated. The residue
was purified by silica gel chromatography (75:25 v/v ethyl acetate/hexane) to give
710 mg of 18C isomer 2.
D. 2-Amino-N-[2-(3a-(R)-benzyl-3-oxo-2.3.3a.4,6,7-hexahydro-pyrazolo[4r3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
To 200 mg (0.34 mmol) of 18C isomer 1 in 12 mL of ethanol was added 6 ml of
concentrated HCI and the mixture was stirred at room temperature for about 2.5 h.
The mixture was concentrated and co-evaporated three times with ethanol to give 20
mg of 18D isomer 1. MS (Cl, NHs) 492 (MH+). 1HNMR (CDsOD): (partial)S 8.42
(br d, 1 H), 7,35 (m, 5 H), 7.18 (m, 5 H), 5.23 (m, 2 H), 4. 91 (m, 1 H), 4.54 (m, 4 H),
3.80 (m, 2 H), 3.63 (m, 1 H), 3.12 (m, 1 H), 3.07 (m, 3 H), 2.61 (m, 3 H), 1.62 (m, 6
H), 1.39(m, 1 H).
E. 2-Amino-N-[2-(3a-(S)-benzyl-3-oxo-2.3.3a.4.6.7-hexahydro-pyrazolo[4.3-
c]pyridin-5-yl)-1-(R)-benzyloxymethyl-2-oxo-ethyl]-isobutyramide hydrochloride
To 200 mg (0.34 mmol) of 18C isomer 2 in 20 mL of ethanol was added 10 ml of
concentrated HCI and the mixture was stirred at room temperature for about 2.5 h.
The mixture was concentrated and co-evaporated three times with ethanol to give 30
mg of 18E isomer 2. MS (Cl, NHa) 492 (MH+). 1HNMR (CDaOD): (partial) 5 8.29
(br d, 1 H), 7.30 (m, 5 H), 7.11 (m, 4 H), 6.88 (m, 1 H), 5.29 (m. 1 H), 4.92 (m, 1 H),
4.62 (m, 3 H), 3.91-3.70 (m, 3 H), 3.22-2.95 (m, 3 H), 2.66 (m, 3 H), 1.57 (m, 6 H),
1.30(m, 1 H), 0.89 (m, 1 H).
Example 19
2-Amino-N-[1-'(R)-benzyloxymethyl-2-f2-methyl-3-oxo-3a-(;R.SVthiazol-4-ylmethyl-
2,3,3a.4,6,7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-isobutyramide
dihydrochloride
A. 4-Oxo-3-(R.S)-thiazol-4-ylrnethyl-piperidine-1.3-dicarboxylic acid 1 -tert-butyl
ester 3-ethyl ester
To a solution of 300 mg (1.10 mmol) of 1A in 5 mL of THF at about 0 °C was added
67 mg (1.66 mmol) of sodium hydride (60% oil dispersion) and the mixture was
stirred for about 30 min. A solution of 204 mg ( 1.21 mmol) of 4-chloromethylthiazole
(Hsiao, C. N; Synth. Comm. 20, p. 3507 (1990)) in 5 mL of THF was added
to the cold solution, followed by 87 mg (0.53 mmol) of potassium iodide and the
mixture was heated at reflux for about 17 h. The mixture was diluted with water and
extracted with ethyl acetate. The combined organic extracts were dried over
Na2SC4 and concentrated and the residue was purified by silica gel chromatography
(7:3 v/v hexane:ethyl acetate) to give 90 mg of the title compound. MS (Cl, NH3)
B. 2-Methyl-3-oxo-3a-(R,S)-thiazol-4-ylmethyl-2.3.3a.4.6.7-hexahydropyrazolo[
4,3-c]pyridine-5-carboxylic acid tert-butyl ester
To 90 mg (0.24 mmol) of 19A in 2 mL of ethanol was added 11.2 mg (0.24 mmol) of
methylhydrazine and the mixture was heated at reflux for about 17 h. An additional
33.6 mg (0.72 mmol) of methylhydrazine was added and the mixture was heated at
reflux for about 7 h. The mixture was concentrated and the residue was dissolved in
3 ml of toluene and heated at reflux for about 17 h. The mixture was concentrated
and the residue was purified by silica gel chromatography (6:4 v/v hexane:ethyl
acetate) to give 44 mg of 19B. MS (Cl, NHa) 648 (MH+).
C. 2-Methyl-3a-;R.S)-thiazol-4-ylmethyl-2.3a.4.5.6.7-hexahydro-pyra2olo[4.3-
A mixture of 44 mg (0.10 mmol) of 19B in 1 ml of 4M HCI in dioxane was stirred at
room temperature for about 4 h. The mixture was concentrated and co-evaporated
with methylene chloride to give 40 mg of 19C. MS (Cl, NHs) 251 (MH+).
D. {1-[1-(R)-Benzyloxymethyl-2-r2-methyl-3-oxo-3a-(R.SMhiazol-4-ylrnethyl-
2,3,3a.4,6,7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethylcarbamoyl]-1-
According to the method outlined in General Procedure A, 40 mg (0.12 mmol) of 19C
and 39 mg (0.12 mmol) of 14F were coupled and the residue was purified by silica
gel chromatography (9:1 v/v ethyl acetate:hexane) to give 40 mg of 19D. MS (Cl,
E. 2-Amino-N-[1-(R)-benzyloxymethyl-2-(2-methyl-3-oxo-3a-(R,S)-thiazol-4-
ylmethyl-2,3,3a,4.6,7-hexahydro-pyrazolo[4.3-c]pyridin-5-yl)-2-oxo-ethyl]-
isobutyramide dihydrochloride
A mixture of 40 mg (0.06 mmol) of 19D in 1 ml of 4M HCI in dioxane was stirred at
room temperature for about 5 h. The mixture was concentrated and co-evaporated
with methylene chloride to give 40 mg of 19E. MS (Cl, NHs) 513 (MH+).
2-Amino-N-[2-(3a-(RVbenzyl-2-methyl-3-oxo-2.3.3a.4.6.7-hexahvdro-pvrazolo[4.3-
c]pvridin-5-vn-1 2-oxo-ethyl]-isobutyramide L-tartaric acid
To 4.6 g of the title compound of Example 14 in 20 ml of methanol, a solution of
1.36 g of L-tartaric acid in 20 ml_ of methanol was added at about 0° C. The mixture
was warmed to room temperature, stirred for about 40 min and concentrated in
vacua. The residue was diluted with 220 ml of ethyl acetate, heated at reflux for
about 1.5 h, then stirred at about 72° C for about 18 h. The mixture was cooled to
room temperature, and filtered to give 5.78 g of the title compound as a colorless
3-Benzyl-3-methoxycarbonylmethyl-4-oxo-piperidine-1-carboxylic acid tert-butyl
A. 3-Benzyl-4-oxo-piperidine-1 -carbpxyh'c acid tert-butyl ester
A mixture of the p-ketoester (4480 mg, 12.9 mmol) and LiCI (1100 mg, 25.8
mrnol) was heated in DMF (2.0 ml) at about 120 °C for about 17 h. The reaction
mixture was cooled to room temperature and extracted with EtOAc (3 x 100 mL).
The combined extracts were dn'ed and concentrated in vacua. The crude product
was chromatographed on SiO2 using 20% ethyl acetate/hexanes to give 1320 mg of
the desired product as a yellow oil. 1H NMR (250 MHz, CDCI3): d: 7.4 (m, 5H), 4.2
(m, 1H), 3-4 (m, 1 H), 3.3 (dd, 1 H), 3.05 (dd, 1 H), 2.7 (m, 1H), 2.55 (m, 4H), 1.5 (s,
B. 3-Benzyl-3-methQxycartx?nylmethyl-4-oxo-piperjdine-1 -carboxyljc gpid tertbutyl
A solution of the product from Step A of Example 21 above (1320 mg, 4.56
mmol), pyrrolidine ( 972 mg, 13 mmol) and p-toluenesulfonic acid (33 mg) in
benzene (30 ml) was refluxed through 3#f molecular sieves for about 17 h. The
reaction mixture was cooled to room temperature and concentrated in vacua. The
residue was dissolved in benzene (10 ml) and cooled to about 0 °C. Methyl
bromoacetate (1530 mg, 10 mmol) was added dropwise. The reaction mixture was
slowly allowed to warm to room temperature and then was heated under reflux for
about 17 h at which point H2O (5 ml) was added. After refluxing for about another 2
h, the reaction mixture was cooled to room temperature and extracted with EtOAc (3
x 100 ml). The combined organic extracts were dn'ed and concentrated in vacua.
The crude residue was chromatographed on SiO2-gel using 15% ethyl acetate/
hexanes to give 280 mg of product. 'H NMR (250 MHz, CDCI3): d 7.35 (m, 5 H), 4.5
(m, 1 H), 3.8 (s, 3H), 3.4 (dd, 1 H), 3.1 (m, 1 H), 2.85 (m, 4H), 2.6 (m, 1 H), 2.4 (m, 1
H), 1.5 (s, 9 H); MS (APCI): 362 (M+1).
6-Oxo-l -phenyl-cyclohexane-1,3-dicarboxylic acid 3-tert-butyl ester 1-methyl ester
A solution of diphenylmercury (890 mg, 2.5 mmol) in CHCI3 (4 ml) under N2
was heated to about 40 °C. Lead tetraacetate (1110 mg, 2.5 mmol) was added in
small portions and the greenish yellow solution was stirred at about 40 °C for about
0.5 h. The (J-ketoester (520 mg, 2.0 mmol) was then added, followed by pyridine
(0.2 ml, 2.5 mmol). After about 5 h at about 40 °C, the reaction mixture was
concentrated in vacua and the residue was dissolved in ether (100 ml) and filtered.
The filtrate was washed with 3N H2SO4 (3x), dried and concentrated to give 616 mg
of a yellow solid. Flash chromatography over SiO2-gel using 25% ethyl
acetate/hexanes provided 368 mg of the desired product . 1H NMR (400 MHz,
CDCI3): d 7.15 (m, 5 H), 4.4 (s, 2 H), 3.7 (s, 5 H), 2.6 (s, 2 H), 1.5 (s, 9H); MS
(D)-2-Amino-3-(2,4-dichloro-benzyloxy)-propionicacid hydrochloride
A. (D)-2-tert-ButQxycaffaonylamino-3-(2.4-dichloro-benzyloxy)-propionicacid
To a stirred solution of Boc-D-serine (8.2 g, 40 mmol) in DMF (75 ml) at
about 0°C was added NaH (60% dispersion, 3.2 g,.80 mmol) over about a 10 minute
period. The reaction mixture was stirred for about 1.75 h at about 0 °C, then about
0.25 h at room temperature. After cooling to about 0 °C, a solution of 2,4-
dichlorotoluene (5.56 ml, 40 mmol) in DMF (5 ml) was added dropwise. The
reaction mixture was allowed to warm to about 23 °C and was stirred for about 17 h,
then was partitioned between di-isopropylether and 10% HCI. The aqueous solution
was extracted with di-isopropyl ether (2x). The combined extracts were washed with
saturated aqueous brine, dried and concentrated to give 14.75 g of crude product
which was used without further purification. 1H NMR (400 MHz, CDCI3): d 7.6-7.2
(m, 3 H), 5.4 (d, 1 H), 4.6 (s, 2 H), 4.0 (d, 1 H), 3.8 (dd, 2 H), 1.1 (s, 9H); MS (APCI):
264,266 (M+1.M+2).
B. (D)-2-Amino-3-(2.4-dichloro-benzyloxy)-propionic acid hydrochloride
The product from step A of Example 23 above (14.7 g, 40 mmol) was stirred
in 4 M HCI/dtoxane (100 ml) for about 17 h. The reaction mixture was concentrated
in vacua to give 12 g of a pale yellow solid (100%). MS (APCI): 265 (M+1).
Example 24 having the formula shown below,
wherein R1 is -CH2-phenyl and R2 is methyl, was synthesized in an analogous
manner to the procedures described in Examples 3C to 3F using the title compound
of Example 21 as starting material. Both the R,R and S,R diastereomers (* indicates
the other stereoisomer center at the C-3 carbon of the above structure) were
isolated. Mass spec. (M+1)= 520; MS method = particle bombardment.
wherein for both examples 25 and 26 R1 is phenyl and R2 is methyl, where example
25 is the R,R isomer and example 26 is the S,R isomer. Examples 25 and 26 were
synthesized in an analogous manner to the procedures described in Examples 3C to
3F using the title compound of Example 22 as starting material followed by
chromatographic separation of the two separate isomers. Mass spec, of each
example (M+1)= 493, MS method= particle bombardment.
Examples 27 to 159 listed in the table below, were prepared according to the
scheme illustrated below by coupling the appropriately substituted pyrazalonepiperidine
of formula I (in the below scheme) with the (D)-OBnSer derivative II (in the
below scheme) in an analogous manner to the procedures described in Examples 3E(Table Removed)





WE CLAIM:
1. A fused tetrahydropyridazine and dihydropyrazole compound of the formula:
(Formula Removed)
the racemic-diastereomeric mixtures and optical isomers of said compounds, wherein
Z100 is hydrogen, methyl, BOC, CBZ, CF3C(O)-, FMOC, TROC, trityl, tosyl, CH3C(O)- or
optionally substituted benzyl which is optionally substituted with methoxy, dimethoxy or
nitro;
e is 0 or 1;
n and w are each independently 0, 1 or 2, provided that w and n cannot both be 0 at the same
time;
R1 is hydrogen, -CN, -(CH2)qN(X6)C(O)X6,-(CH2)qN(X6)C(O)(CH2)t-A1,
-(CH2)qN(X6)SO2(CH2)t-A1, -(CH2)N(X6)(X6)SO2X6, -(CH2)qN(X6)C(O)N(X6)(CH2)t-A1,
-(CH2)qN(X6)C(O)N(X6)(X6),-(CH2)qC(O)N(X6)(X6),-(CH2)qC(O)N(X6)(X6)(CH2)t-A1,
-(CH2)qC(O)OX6, -(CH2)qC(O)O(CH2)t-A1, -(CH2)qOX6, -(CH2)qOC(O)X6,
-(CH2)qO(O)(CH2)t-A1-(CH2)qO(O)N(X6)(CH2)t-A1-(CH2)qOC(O)N(X6)(X6),
-(CH2)qC(O)X6, -(CH2)qC(O)(CH2)t-A1, -(CH2)qN(X6)C(O)OX6,
-(CH2)qN(X6)SO2N(X6)(X6),-(CH2)qS(O)mX6,-(CH2)qS(O)m(CH2)t-A1,
-(C1- C10)alkyl, (CH2)t-A1, -(CH2)q-(C3- C7)cycloakyl, -(CH2)-Y1-(C1-C6)alkyl,
-(CH2)q-Y1-(CH2)t-A1 or-(CH2)q-Yl-(CH2)t-(C1- C7)cycloalkyl;
where the alkyl and cycloalkyl groups in the definition of R1 are optionally substituted with
(C1- C1)alkyl, hydroxyl, (C1-C4)alkoxy, carboxyl, CONH2, -S(O)m(C1-C6)alkyl,-CO2(C1-
C4)alkyl,lH-tetrazol-5-yl or 1 to 3 fluoro;
Y1 is O, S(O)m,-C(O)NX6, -CH=CH-, -C≡C-,-N(X6)C(O), -C(O)NX6,
-C(O)0, -OC(O)N(X6) or-OC(O);
q is 0, 1, 2, 3, 4;
t is 0,1,2, or 3;
said (CH2)q group and (CH2)t group may each be optionally substituted with hydroxyl, (C1-
C4)alkoxy, carboxyl, -CONH2, -S(O)m(C1- C6)alkyl,
-CO2(C1-C4)alkyl, lH-tetrazol-5-yl, 1 to 3 fluoro 1 or 2 (C1-C4)alkyl;
R2 is hydrogen, (C1-C8)alkyl, -(C0-C3)alkyl-(C3-C8)cycloalkyl, -(C1-C4)alkyl-A1 or A1;
where the alkyl groups and the cycloalkyl groups in the definition of
R2 are optionally substituted with hydroxyl, -C(O)OX6, -C(O)N(X6)(X6), -N(X6)(X6), -
S(O)m(C1-C6)alkyl, -C(O)A1, -C(O)(X6), CF3, CN or 1 to 3 halogen;
A1 for each occurrence is independently (C5-C7)cycloalkenyl, phenyl or a partially saturated,
fully saturated or fully unsaturated 4- to 8-membered ring optionally having 1 to 4
heteroatoms independently selected from the group consisting of oxygen, sulfur and nitrogen,
or a bicyclic ring system consisting of a partially saturated, fully unsaturated or fully
saturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms independently selected
from the group consisting of nitrogen, sulfur, and oxygen, fused to a partially saturated or
fully unsaturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms independently
selected from the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or optionally both rings
if A1 is a bicyclic ring system, with up to three substituents, each substituent independently
selected from the group consisting of F, C1, Br, I, OCF3, OCF2H, CF3, CH3, OCH3, -OX6,
-C(O)N(X6)(X6), -C(O)OX6, oxo, (C1-C6)alkyl, nitro, cyano, benzyl,
-S(O)m(C1-C6)alkyl, lH-tetrazol-5-yl, phenyl, phenoxy, phenylalkyloxy, halophenyl,
methylenedioxy, -N(X6)(X6), -N(X6)C(O)(X6), -SO2N(X6)(X6),
-N(X6)SO2-phenyl, -N(X6)SO2X6, -CONX11X12, - SO2NX11X12, -NX6 SO2X12, -
NX6CONX11X2, -NX6SO2NX1,X12, -NX6C(O)X12, imidazolyl, thiazolyl and tetrazolyl,
provided that if A1 is optionally substituted with methylenedioxy then it can only be
substituted with one methylenedioxy;
where X11 is hydrogen or optionally substituted (C1-C6)alkyl;
the optionally substituted (C1-C6)alkyl defined for X11 is optionally independently substituted
with phenyl, phenoxy, (C1-C6)alkoxycarbonyl, -S(O)m(C1-C6)alkyl, 1 to 5 halogens, 1 to 3
hydroxy, 1 to 3 (C1-C10)alkanoyloxy or 1 to 3 (C1-C6)alkoxy;
X12 is hydrogen, (C1-C6)alkyl, phenyl, thiazolyl, imidazolyl, furyl or thienyl, provided that
when X12 is not hydrogen, X12 is optionally substituted with one to three substituents
independently selected from the group consisting of C1, F, CH3, OCH3, OCF3 and CF3;
or X11 and X12 are taken together to form -(CH2)r-L1-(CH2)r;
L1 is C(X2XX2), O, S(O)m or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted(C1-C6)alkyl, or
optionally substituted (C3-C7)cycloalkyl, where the optionally substituted (C1-C6)alkyl and
optionally substituted (C3-C7)cycloalkyl in the definition of X2 are optionally independently substituted with -S(O)m(C1-C6)alkyl, -C(O)OX3,1 to 5 halogens or 1 to 3 OX3;
X3 for each occurrence is independently hydrogen or (C1-C6)alkyl; X6 for each occurrence is independently hydrogen, optionally substituted (C1-C6)alkyl, (C2-C6)halogenated alkyl, optionally substituted (C3-C7)cycloalkyl, or (C3-C7)-halogenatedcycloalkyl, where optionally substituted (C1 -C6)alkyl and optionally substituted (C3-C7)cycloalkyl in the definition of X6 is optionally independently substituted with hydroxyl, (C1 -C4)alkoxy, carboxyl, CONH2, -S(O)m(C1-C6)alkyl, -CO2(C1-C4)alkyl, 1H-tetrazol-5-yl or 1 or 2 (C1-C4)alkyl; or where there are two X6 groups on one atom and both X6 are (C1-C6)alkyl, the two (C1-C6)alkyl groups may be optionally joined and, together with the atom to which the two X6 groups are attached, form a 4- to 9- membered ring optionally having oxygen, sulfur or NX7;
X7 is hydrogen or (C1-C6)alkyl optionally substituted with hydroxyl; and m for each occurrence is independently 0, 1 or 2; with the proviso that:
X6 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form C(O)X6, C(O)X12, SO2X6 or SO2X12; when R2 is hydrogen then R1 is not -CH=CH-phenyl; when R2 is H and R1 is -CH2-CH=CH-Ph, then Z100 is not BOC; when R2 is H and R1 is (2-cyclohexen-l-yl) then Z100 is not BOC; when R2 is H and R1 is -CH2-C(CH3)=CH2, then Z100 is not BOC; and when R2 is phenyl and R1 is -CH3, then Z100 is not CH3C(O)-.
2. The compound as claimed in claim 1, wherein;
w is 0 or 1;
n is 1;
Z100 is BOC, methyl, benzyl or CBZ;
R1 is hydrogen, (CH2)q-(C3-C7)cycloalkyl, -(CH2)t-A1 or (C1-C10)alkyl where the (C1-
C10)alkyl and (C3-C7)cycloalkyl groups are optionally substituted with 1 to 3 fluoro and A1 in
the definition of R1 is optionally substituted with 1 to 3 substituents independently selected
from the group consisting of F, C1, Me, OMe, CF3, OCF3 and OCF2H;
R2 is hydrogen, (C1-C8)alkyl, -(C0-C3)alkyl-(C3-C7)cycloalkyl, phenyl, or- (C1-C3)alkyl-
phenyl where the alkyl and phenyl groups are optionally substituted with 1 to 3 substituents
independently selected from the group consisting of F, CF3, OH and OMe.
3. The compound as claimed in claim 2 wherein Z100 is BOC; w is 1; e is 0; R1 is -CH2-
pyridyl, -CH2-thiazolyl, or -CH2-phenyl optionally substituted with 1 to 3 substituents
independently selected from the group consisting of fluoro and chloro; and R2 is hydrogen, (C1-C4)alkyl or phenyl where the (C1-C4)alkyl or phenyl groups in the definition of R2 is optionally substituted with 1 to 3 substituents independently selected from the group consisting of fluoro, hydroxy or methoxy.
4. The compound as claimed in claim 3, wherein R1 is -CH2-phenyl and R2 is methyl or hydrogen.
5. The compound as claimed in claim 4, wherein the compound is the 3a-(R) enantiomer.
6. The compound as claimed in claim 5, wherein the compound is the 3a-(S) enantiomer.
7. The compound as claimed in claim 1, wherein Z100 is hydrogen;
eisOorl;
n and w are each independently 0, 1 or 2, provided that w and n cannot both be 0 at the same
time;
R1 is hydrogen, -CN, -(CH2)qN(X6)C(O)X6, -(CH2)qN(X6)C(O)(CH2)t-A1,
-(CH2)qN(X6)SO2(CH2),-A1,-(CH2)qN(X6)SO2X6,
-(CH2)qN(X6)C(O)N(X6)(CH2)rA1,
-(CH2)qN(X6)C(O)N(X6)(X6),-(CH2)qC(O)N(X6)(X6),-(CH2)qC(O)N(X6)(CH2)t-A1,
-(CH2)qC(O)OX6, -(CH2)qC(O)(CH2)t-A1, -(CH2)qOX6, -(CH2)qOC(CO)X6,
-CH2)qOC(O)(CH2)rA1,-(CH2)qOC(O)N(X6)(CH2)rA1,
-(CH2)qOC(O)N(X6)(X6),
-(CH2)qC(O)X6, -(CH2)qC(O)(CH2)t-A1, -(CH2)qN(X6)C(O)X6,
-(CH2)qN(X6)SO2N(X6)(X6), -(CH2)qS(O)mX6, -(CH2)qS(O)m(CH2)t-A1,
-(C1-C10)alkyl, -(CH2)t-A1, -(CH2)q-(C3-C7)cycloalkyl, (CH2)q-Y1(C1-C6)alkyl, (CH2)q-Y1-
(CH2)t-A1 or -(CH2)q-Y1-(CH2)t-(C3-C7)cycloalkyl;
where the alkyl and cycloalkyl groups in the definition of R1 are optionally substituted with
(C1-C4)alkyl, hydroxyl, (C1-C4)alkoxy, carboxyl, CONH2, -S(O)m(C1-C6)alkyl, -CO2(C1-
C4)alkyl, lH-tetrazol-5-yl or 1 to 3 fluoro;
Y1 is O, S(O)m, -C(O)NX6, -CH=CH-, -C=C-, -N((X6)C(O)-, -C(O)NX6-
-C(O)O-, -OC(O)N(X6)- or -OC(O)-;
q is o, 1,2, 3 or 4;
t is o, 1,2 or 3;
said (CH2)q group and (CH2) group may each be optionally substituted with 1 to 3 fluoro, 1 or
2 (C1-C4)alkyl, hydroxyl, (C1-C4)alkoxy, carboxyl, -CONH2, S(O)m(C1-C6)alkyl, -CO2(C1-
C4)alkyl ester, or lH-tetrazol-5-yl;
R2 is hydrogen, (C1-C8)alkyl, -(CO-C3)alkyl-(C3-C8)cycloalkyl, -(C1-C4)alkyl-A1 or A1; where
the alkyl groups and the cycloalkyl groups in the definition of R2 are optionally substituted by
hydroxyl, -C(O)OX6, -C(O)N(X6)(X6), -N(X6)(X6), -S(O)m(C1-C6)alkyl, -C(O)A1, -C(O)(X6),
CF3, CN or 1 to 3 halogen;
A1 for each occurrence is independently (C5-C7)cycloalkenyl, phenyl or a partially saturated,
fully saturated or fully unsaturated 4- to 8-membered ring optionally having 1 to 4
heteroatoms independently selected from the group consisting of oxygen, sulfur and nitrogen,
or a bicyclic ring system consisting of a partially saturated, fully unsaturated or fully
saturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms independently selected
from the group consisting of nitrogen, sulfur and oxygen, fused to a partially saturated, fully
saturated or fully unsaturated 5- or 6-membered ring, optionally having 1 to 4 heteroatoms
independently selected from the group consisting of nitrogen, sulfur and oxygen;
A1 for each occurrence is independently optionally substituted, in one or optionally both rings
if A1 is a bicyclic ring system, with up to three substituents, each substituent independently
selected from the group consisting of F, C1, Br, I, OCF3, OCF2H, CF3, CH3, OCH3, -OX6, -
C(O)N(X6)(X6), -C(O)OX6, oxo, (C1-C6)alkyl, nitro, cyano, benzyl, S(O)m(C1-C6)alkyl, 1H-
tetrazol-5-yl, phenyl, phenoxy, phenylalkyloxy, halophenyl, methylenedioxy, -N(X6)(X6), -
N(X6)C(O)(X6), -SO2N(X6)(X6), -N(X6)SO2-phenyl, -N(X6)SO2X6, -CONX11-X12, -
SO2NX11X12, -NX6SO2X12, -NX6CONX11X12, -NX6SO2NX11X12, -NX6C(O)X12, imidazolyl,
thiazolyl and tetrazolyl, provided that if A1 is optionally substituted with methylenedioxy
then it can only be substituted by one methylenedioxy; where X11 is hydrogen or optionally
substituted (C1-C6)alkyl; the optionally substituted (C1-C6)alkyl defined for X11 is optionally
independently substituted with phenyl, phenoxy, (C1-C6)alkoxycarbonyl, -S(O)m(C1-
C6)alkyl, 1 to 5 halogens, 1 to 3 hydroxy, 1 to 3 (C1-C10)alkanoyloxy or 1 to 3 (C1-C6)alkoxy
X12 is hydrogen, (C1-C6)alkyl, phenyl, thiazolyl, imidazolyl, furyl or thienyl, provided that
when X12 is not hydrogen, X12 is optionally substituted with one to three substituents
independently selected from the group consisting of C1, F, CH3, OCH3, OCF3 and CF3;
or X" and X12 are taken together to form -(CH2)r-L1-(CH2)r-;
L1 is C(X2)(X2), O, S(O)m, or N(X2);
r for each occurrence is independently 1, 2 or 3;
X2 for each occurrence is independently hydrogen, optionally substituted (C1-C6)alkyl, or
optionally substituted (C3-C7)cycloalkyl, where the optionally substituted (C1-C6)alkyl and
optionally substituted (C3-C7)cycloalkyl in the definition of X2 are optionally independently
substituted with -S(O)m(C1-C6)alkyl, -C(O)OX3,1 to 5 halogens or 1 to 3 OX3;
X3 for each occurrence is independently hydrogen or (C1-C6)alkyl;
X6 for each occurrence is independently hydrogen, optionally substituted (C1-C6)alkyl, (C2-
C6)halogenated alkyl, optionally substituted (C3-C7)cycloalkyl, or (C3-C7)-
halogenatedcycloalkyl, where optionally substituted (C1-C6)alkyl and optionally substituted
(C3-C7)cycloalkyl in the definition of X6 is optionally independently substituted with
hydroxyl, (C1-C4)alkoxy, carboxyl, CONH2, -S(O)m(C1-C6)alkyl, -CO2(C1-C4)alkyl, 1H-
tetrazol-5-yl or 1 or 2 (C1-C4)alkyl; or where there are two X6 groups on one atom and both
X6 are (C1-C6)alkyl, the two (C1-C6)alkyl groups may be optionally joined and, together with
the atom to which the two X6 groups are attached, form a 4- to 9- membered ring optionally
having oxygen, sulfur or NX7;
X7 is hydrogen or (C1-C6)alkyl optionally substituted with hydroxyl; and m for each
occurrence is independently 0, 1 or 2; with the proviso that:
X6 and X12 cannot be hydrogen when it is attached to C(O) or SO2 in the form C(O)X6,
C(O)X12, SO2X6 or SO2X12 and
when R2 is hydrogen then R1 is not -CH=CH-phenyl.
8. The compound as claimed in claim 7, wherein
w is o or 1;
n is 1;
R1 is hydrogen, -(CH2)q-(C3-C7)cycloalkyl, -(CH2)t-A1 or (C1-C10)alkyl where the (C1-
C10)alkyl and (C3-C7)cycloalkyl groups are optionally substituted with 1 to 3 fluoro and A1 in
the definition of R1 is optionally substituted with 1 to 3 substituents independently selected
from the group consisting of F, Cl, Me, methoxy, CF3, OCF3 and OCF2H;
R2 is hydrogen, (C1-C8)alkyl, (C0-C3)alkyl-(C3-C7)cycloalkyl, phenyl, or (C1-C3)alkyl- phenyl
where the alkyl and phenyl groups are optionally substituted with 1 to 3 substituents
independently selected from the group consisting of F, CF3, OH and methoxy.
9. The compound as claimed in claim 8, wherein w is 1, e is 0, R1 is CH2-pyridyl, -CH2-
thiazolyl, or -CH2-phenyl optionally substituted with 1 to 3 substituents independently
selected from the group consisting of fluoro and chloro; and R2 is hydrogen, (C1-C4)alkyl or
phenyl where the (C1-C4)alkyl or phenyl groups in the definition of R2 is optionally
substituted with 1 to 3 substituents independently selected from the group consisting of fluoro, hydroxy or methoxy.
10. The compound as claimed in claim 9 wherein R1 is -CH2-phenyl and R2 is methyl or hydrogen.
11. The compound as claimed in claim 10 wherein the compound is the 3a- (R) enantiomer.
12. The compound as claimed in claim 10 wherein the compound is the 3a- (S) enantiomer.

Documents:

781-DEL-2007-Abstract-(12-06-2012).pdf

781-del-2007-Abstract-(20-12-2011).pdf

781-del-2007-abstract.pdf

781-DEL-2007-Assignment-(11-03-2010).pdf

781-DEL-2007-Claims-(12-06-2012).pdf

781-del-2007-Claims-(20-12-2011).pdf

781-del-2007-claims.pdf

781-DEL-2007-Correspondence Others-(12-06-2012).pdf

781-DEL-2007-Correspondence-Others-(11-03-2010).pdf

781-del-2007-Correspondence-Others-(20-12-2011).pdf

781-del-2007-correspondence-others-1.pdf

781-del-2007-correspondence-others.pdf

781-del-2007-description (complete).pdf

781-del-2007-Form-1-(20-12-2011).pdf

781-del-2007-form-1.pdf

781-del-2007-form-18.pdf

781-del-2007-Form-2-(20-12-2011).pdf

781-del-2007-form-2.pdf

781-del-2007-Form-3-(20-12-2011).pdf

781-del-2007-form-3.pdf

781-del-2007-form-5.pdf

781-DEL-2007-GPA-(11-03-2010).pdf

781-del-2007-GPA-(20-12-2011).pdf

781-del-2007-gpa.pdf

781-del-2007-Petition-137-(20-12-2011).pdf

abstract.jpg


Patent Number 265629
Indian Patent Application Number 781/DEL/2007
PG Journal Number 10/2015
Publication Date 06-Mar-2015
Grant Date 02-Mar-2015
Date of Filing 09-Apr-2007
Name of Patentee RAQUALIA PHARMA INC.,
Applicant Address 2, AZA 5-GOCHI, TAKETOYO-CHO, CHITA-GUN, AICHI-KEN, 470-2341, JAPAN
Inventors:
# Inventor's Name Inventor's Address
1 PHILIP A.CARPINO 50 MERIDIAN STREET #2, GROTON, CONNECTICUT 06340, USA
2 BRUCE A.LEFKER 21 EAGLE RIDGE DRIVE, GALES FERRY, CONNECTICUT 06335, USA
3 JOHN A.RAGAN 1 LARK LANE, GALES FERRY, CONNECTICUT 06335, USA
4 PAUL A.DASILVA JARDINE 89 ANGELL STREET, PROVIDENCE, RHODE ISLAND 02906, USA
PCT International Classification Number C07C
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/009,469 1995-12-28 U.S.A.