U.S. patent application number 12/633265 was filed with the patent office on 2010-06-17 for piperidine derivatives.
Invention is credited to Giuseppe Alvaro, Romano Di Fabio, Simone Spada, Maria Tranquillini.
Application Number | 20100152446 12/633265 |
Document ID | / |
Family ID | 9930717 |
Filed Date | 2010-06-17 |
United States Patent
Application |
20100152446 |
Kind Code |
A1 |
Alvaro; Giuseppe ; et
al. |
June 17, 2010 |
Piperidine Derivatives
Abstract
The present invention relates to piperidine derivatives of
formula (I) ##STR00001## R represents halogen or C.sub.1-4 alkyl;
R.sub.1 represents C.sub.1-4 alkyl; R.sub.2 or R.sub.3
independently represent hydrogen or C.sub.1-4 alkyl; R.sub.4
represents trifluoromethyl, C.sub.1-4 alkyl, C.sub.1-4 alkoxy,
trifluoromethoxy or halogen; R.sub.5 represents hydrogen, C.sub.1-4
alkyl or C.sub.3-7 cycloalkyl; R.sub.6 is hydrogen and R.sub.7 is a
radical of formula (W): ##STR00002## or R.sub.6 is a radical of
formula (W) and R.sub.7 is hydrogen; X represents CH.sub.2,
NR.sub.5 or O; Y represents Nitrogen and Z is CH or Y represents CH
and Z is Nitrogen; A represents C(O) or S(O)q, provided that when Y
is nitrogen and Z is CH, A is not S(O)q; m is zero or an integer
from 1 to 3; n is an integer from 1 to 3; p and q are independently
an integer from 1 to 2; and pharmaceutically acceptable salts and
solvates thereof. The process for their preparation and their use
in the treatment of condition mediated by tachykinins.
Inventors: |
Alvaro; Giuseppe; (Verona,
IT) ; Di Fabio; Romano; (Verona, IT) ;
Tranquillini; Maria; (Verona, IT) ; Spada;
Simone; (Verona, IT) |
Correspondence
Address: |
GLAXOSMITHKLINE;CORPORATE INTELLECTUAL PROPERTY, MAI B482
FIVE MOORE DR., PO BOX 13398
RESEARCH TRIANGLE PARK
NC
27709-3398
US
|
Family ID: |
9930717 |
Appl. No.: |
12/633265 |
Filed: |
December 8, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11608853 |
Dec 11, 2006 |
7652012 |
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12633265 |
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10502255 |
Mar 28, 2005 |
7189713 |
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PCT/EP03/01308 |
Feb 10, 2003 |
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11608853 |
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Current U.S.
Class: |
544/349 |
Current CPC
Class: |
A61P 25/04 20180101;
A61P 25/28 20180101; A61P 29/00 20180101; A61P 25/00 20180101; A61P
25/06 20180101; A61K 31/445 20130101; A61P 25/18 20180101; A61P
1/00 20180101; A61P 1/04 20180101; A61P 25/30 20180101; A61P 25/20
20180101; A61P 25/08 20180101; A61P 1/08 20180101; A61P 25/22
20180101; A61P 25/24 20180101; A61P 43/00 20180101; C07D 487/04
20130101; A61P 37/08 20180101 |
Class at
Publication: |
544/349 |
International
Class: |
C07D 487/04 20060101
C07D487/04 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 8, 2002 |
GB |
0203020.3 |
Claims
1. A compound of formula (I) ##STR00026## R represents halogen or
C.sub.1-4 alkyl; R.sub.1 represents C.sub.1-4 alkyl; R.sub.2 or
R.sub.3 independently represent hydrogen or C.sub.1-4 alkyl;
R.sub.4 represents trifluoromethyl, C.sub.1-4 alkyl, C.sub.1-4
alkoxy, trifluoromethoxy or halogen; R.sub.5 represents hydrogen,
C.sub.1-4 alkyl or C.sub.3-7 cycloalkyl; R.sub.6 is hydrogen and
R.sub.7 is a radical of formula (W): ##STR00027## or R.sub.6 is a
radical of formula (W) and R.sub.7 is hydrogen; X represents
CH.sub.2, NR.sub.5 or O; Y represents Nitrogen and Z is CH or Y
represents CH and Z is Nitrogen; A represents C(O) or S(O)q,
provided that when Y is nitrogen and Z is CH, A is not S(O)q; m is
zero or an integer from 1 to 3; n is an integer from 1 to 3; p and
q are independently an integer from 1 to 2; and pharmaceutically
acceptable salts and solvates thereof.
2. A compound as claimed in claim 1 in which R.sub.6 is hydrogen,
R.sub.7 is a radical of formula (W) and Y is CH and Z is nitrogen
or wherein R.sub.6 is a radical of formula (W), R.sub.7 is a
hydrogen and Y is nitrogen and Z is CH.
3. A compound as claimed in claim 1 or claim 2 wherein A is
C(O).
4. A compound as claimed in any claims from 1 to 3 wherein X is
CH.sub.2.
5. A compound as claimed in any claims from 1 to 4 wherein p is
1.
6. A compound as claimed in any claims from 1 to 5 wherein each
R.sub.4 is independently trifluoromethyl group or halogen (e.g.
chlorine) and n is 2.
7. A compound as claimed in any claims from 1 to 6 wherein each R
is independently a halogen (e.g. fluorine) or a C.sub.1-4 alkyl
(e.g. methyl) group, wherein m is 0, 1 or 2.
8. A compound as claimed in any claims from 1 to 7 in which R.sub.6
is hydrogen, R.sub.7 is a radical of formula (W) and Y is CH and Z
is nitrogen or wherein R.sub.6 is a radical of formula (W), R.sub.7
is a hydrogen and Y is nitrogen and Z is CH; A is C(O) and X is
CH.sub.2.
9. A compound as claimed in any claims from 1 to 8 in which R.sub.6
is hydrogen, R.sub.7 is a radical of formula (W) and Y is CH and Z
is nitrogen or wherein R.sub.6 is a radical of formula (W), R.sub.7
is a hydrogen and Y is nitrogen and Z is CH, A is C(O), X is
CH.sub.2, R is independently a halogen (e.g. fluorine) or a
C.sub.1-4 alkyl (e.g. methyl) group; R.sub.4 is a trifluoromethyl
group; m is 1 or 2; n is 2 and p is 1.
10. A compound selected from:
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-py-
razin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide;
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-py-
razin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide;
1-(4-Fluoro-2-methyl-phenyl)-4-(6-oxo-hexahydro-pyrrolo[1,2-a]pyrazin-2-y-
l)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide; and enantiomers,
diastereoisomers pharmaceutically acceptable salts (e.g.
hydrochloride, methanesulphonate or maleate) and solvates
thereof.
11. A compound selected from:
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-M-pyrazin-2-ylypiperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl]-ethyl]-methylamide;
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-ylypiperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide; and
amorphous and crystalline forms thereof and pharmaceutically
acceptable salts (e.g. hydrochloride or maleate) and solvates
thereof.
12. A compound as claimed in any claims from 1 to 11 for use in
therapy.
13. The use of a compound as claimed in any claims from 1 to 11 in
the preparation of a medicament for use in the treatment of
conditions mediated by tachykinins, including substance P and other
neurokinins.
14. The use of a compound as claimed in any claims from 1 to 11 in
the treatment of conditions mediated by tachykinins, including
substance P and other neurokinins.
15. A pharmaceutical composition comprising a compound as claimed
in any claims from 1 to 11 in admixture with one or more
pharmaceutically acceptable carriers or excipients.
16. A method for the treatment of a mammal, including man, in
particular in the treatment of conditions mediated by tachykinins,
including substance P and other neurokinins, comprising
administration of an effective amount of a compound as claimed in
any claims from 1 to 11.
17. A process for the preparation of a compound as claimed in any
claims from 1 to 11, which comprises reacting a compound of formula
(II),), wherein R.sub.8 is .dbd.O and R.sub.9 is hydrogen or
R.sub.8 is hydrogen and R.sub.9 is .dbd.O ##STR00028## with
compound of formula (III) or a salt thereof in the presence of a
suitable metal reducing agent, followed where necessary or desired
by one or more of the following steps: i) removal of any protecting
group; ii) isolation of the compound as a salt or a solvate
thereof; iii) separation of a compound of formula (I) or derivative
thereof into the enantiomers thereof.
Description
[0001] The present invention relates to diazabicycle derivatives,
to processes for their preparation, to pharmaceutical compositions
containing them and to their medical use.
[0002] In particular, the invention relates to novel compounds
which are potent and specific antagonists of tachykinins, including
substance P and other neurokin ins.
[0003] Thus, the present invention provides compounds of formula
(I)
##STR00003##
R represents halogen or C.sub.1-4 alkyl; R.sub.1 represents
C.sub.1-4 alkyl; R.sub.2 or R.sub.3 independently represent
hydrogen or C.sub.1-4 alkyl; R.sub.4 represents trifluoromethyl,
C.sub.1-4 alkyl, C.sub.1-4 alkoxy, trifluoromethoxy or halogen;
R.sub.5 represents hydrogen, C.sub.1-4 alkyl or C.sub.3-7
cycloalkyl; R.sub.6 is hydrogen and R.sub.7 is a radical of formula
(W):
##STR00004##
or R.sub.6 is a radical of formula (W) and R.sub.7 is hydrogen; X
represents CH.sub.2, NR.sub.5 or O; Y represents Nitrogen and Z is
CH or Y represents CH and Z is Nitrogen; A represents C(O) or
S(O)q, provided that when Y is nitrogen and Z is CH, A is not
S(O)q; m is zero or an integer from 1 to 3; n is an integer from 1
to 3; p and q are independently an integer from 1 to 2; and
pharmaceutically acceptable salts and solvates thereof.
[0004] A further embodiment of the invention is
##STR00005##
wherein A represents C(O) or S(O)q; X represents CH.sub.2, NR.sub.5
or O; R represents halogen atom or C.sub.1-4 alkyl; R.sub.1
represents a C.sub.1-4 alkyl group; R.sub.2 or R.sub.3
independently represent hydrogen or C.sub.1-4 alkyl; R.sub.4
represents trifluoromethyl, C.sub.1-4 alkyl, C.sub.1-4 alkoxy,
trifluoromethoxy or a halogen; R.sub.5 represents hydrogen,
C.sub.1-4 alkyl or C.sub.3-7 cycloalkyl; m is zero or an integer
from 1 to 3; n is an integer from 1 to 3; p or q are independently
an integer from 1 to 2; and pharmaceutically acceptable salts and
solvates thereof.
[0005] Suitable pharmaceutically acceptable salts of the compounds
of general formula (I) include acid addition salts formed with
pharmaceutically acceptable organic or inorganic acids, for example
hydrochlorides, hydrobromides, sulphates, alkyl- or arylsulphonates
(e.g. methanesulphonates or p-toluenesulphonates), phosphates,
acetates, citrates, succinates, tartrates, trifluoroacetates,
lactates, fumarates, malates and maleates.
[0006] The solvates may, for example, be hydrates.
[0007] References hereinafter to a compound according to the
invention include both compounds of formula (I) and their
pharmaceutically acceptable acid addition salts together with
pharmaceutically acceptable solvates.
[0008] Suitable pharmaceutical acceptable salts of the compounds of
general formula (I) may be obtained in a crystalline form and/or in
an amorphous form or as a mixture thereof.
[0009] It will be appreciated by those skilled in the art that the
compounds of formula (I) contain at least three chiral centres
(namely the carbon atom shown as * in the formulae from 1a to
4h).
[0010] Thus, when R.sub.6 is hydrogen, R.sub.7 is a radical of
formula (W), Z is nitrogen and Y is carbon, the chiral centres may
be represented by the formulae (1a, 1b, 1c, 1d, 1e, 1f, 1g and
1h)
##STR00006## ##STR00007##
[0011] When R.sub.7 is hydrogen, R.sub.6 is a radical of formula
(W), Z is CH and Y is nitrogen, the chiral centres may be
represented by the formulae (2a, 2b, 2c, 2d, 2e, 2f, 2g and 2h)
##STR00008## ##STR00009## ##STR00010##
[0012] When R.sub.6 is hydrogen, R.sub.7 is a radical of formula
(W), Z is CH and Y is nitrogen, the chiral centres may be
represented by the formulae (3a, 3b, 3c, 3d, 3e, 3f, 3g and 3h)
##STR00011## ##STR00012##
[0013] When R.sub.7 is hydrogen, R.sub.6 is a radical of formula
(W), Z is nitrogen and Y is carbon, the chiral centres may be
represented by the formulae (4a, 4b, 4c, 4d, 4e, 4f, 4g and 4h)
##STR00013## ##STR00014## ##STR00015##
[0014] The wedge shaped bond indicates that the bond is above the
plane of the paper and it is referred to as .beta. configuration.
The broken bond indicates that the bond is below the plane of the
paper and is in the .alpha. configuration.
[0015] In the specific compounds named below when Y is CH and Z is
Nitrogen, the .beta. configuration at the 2 position of the
piperidine ring corresponds to the R configuration and the .beta.
configuration at 4 position of the piperidine ring corresponds to
the S configuration. The .alpha. configuration at the 2 position of
the piperidine ring corresponds to the S configuration and the
.alpha. configuration at 4 position of the piperidine ring
corresponds to the R configuration.
[0016] In the specific compounds named below when Y is Nitrogen and
Z is CH, the 13 configuration at the 2 position of the piperidine
ring corresponds to the S configuration and the 13 configuration at
4 position of the piperidine ring corresponds to the S
configuration. The .alpha. configuration at the 2 position of the
piperidine ring corresponds to the R configuration and the .alpha.
configuration at 4 position of the piperidine ring corresponds to
the R configuration.
[0017] The assignment of the R or S configuration at the 2 and the
4 positions has been made according to the rules of Cahn, Ingold
and Prelog, Experientia 1956, 12, 81.
[0018] The configuration of the chiral carbons atom of the
piperidine ring shown in formulae from 1c to 1f, from 2c to 2f,
from 3c to 3f and from 4c a 4f is hereinafter referred to as anti
configuration and in formulae 1a, 1b, 1g, 1h, 2a, 2b, 2g, 2h, 3a,
3b, 3g, 3h, 4a, 4b, 4g and 4h as the syn configuration.
[0019] Further asymmetric carbon atoms are possible in the
compounds of formula (I). Thus, when R.sub.2 and R.sub.3 are not
the same group, the compounds of formula (I) possess at least four
asymmetric carbon atoms.
[0020] It is to be understood that all stereoisomeric forms,
including all enantiomers, diastereoisomers and all mixtures
thereof, including racemates, are encompassed within the scope of
the present invention and the reference to compounds of formula (I)
includes all stereoisomeric forms unless otherwise stated.
[0021] Compounds (I) may be obtained as a crystalline form. Thus
for example Compounds of formula (I) may be obtained as an
anhydrous crystalline form or as a dihydrate crystalline form or a
mixture thereof. It is to be understood that these crystalline
forms or a mixture thereof are encompassed within the scope of the
invention.
[0022] Furthermore, some of the crystalline forms of the compounds
of structure (I) may exist as polymorphs, which are included in the
present invention.
[0023] The present invention also includes isotopically-labelled
compound. Examples of isotopes that can be incorporated into
compounds of the invention include isotopes of hydrogen, carbon,
nitrogen, oxygen, phosphorous, fluorine, iodine, and chlorine, such
as .sup.3H, .sup.11C, .sup.14C, .sup.18F, .sup.123I and
.sup.125I.
[0024] Compounds of the present invention and pharmaceutically
acceptable salts of said compounds that contain the aforementioned
isotopes and/or other isotopes of other atoms are within the scope
of the present invention. Isotopically-labelled compounds of the
present invention, for example those into which radioactive
isotopes such as .sup.3H, .sup.14C are incorporated, are useful in
drug and/or substrate tissue distribution assays. Tritiated, i.e.,
.sup.3H, and carbon-14, i.e., .sup.14C, isotopes are particularly
preferred for their ease of preparation and detectability. .sup.11C
and .sup.18F isotopes are particularly useful in PET (positron
emission tomography) and .sup.125I are particularly useful in SPECT
(single photon emission computerized tomography), all useful in
brain imaging. Furthermore, substitution with heavier isotopes such
as deuterium, i.e., .sup.2H, can afford certain therapeutic
advantages resulting from greater metabolic stability, for example
increased in vivo half-life or reduced dosage requirements and,
hence, may be preferred in some circumstances. Isotopically
labelled compounds of formula (I) of this invention can generally
be prepared by carrying out the procedures disclosed in the Schemes
and/or in the Examples below by substituting a readily available
isotopically labelled reagent for a non-isotopically labelled
reagent.
[0025] The term C.sub.1-4 alkyl as used herein as a group or a part
of the group refers to a straight or branched alkyl group
containing from 1 to 4 carbon atoms; examples of such groups
include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl or tert
butyl.
[0026] The term C.sub.1-4 alkoxy group may be a straight chain or a
branched chain alkoxy group, for example methoxy, ethoxy, propoxy,
prop-2-oxy, butoxy, but-2-oxy or methylprop-2-oxy.
[0027] The term halogen refers to a fluorine, chlorine, bromine or
iodine atom.
[0028] The term C.sub.3-7 cycloalkyl group means a non aromatic
monocyclic hydrocarbon ring of 3 to 7 carbon atoms such as, for
example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl or
cycloheptyl.
[0029] A group of preferred compounds of the invention is that in
which R.sub.6 is hydrogen, R.sub.7 is a radical of formula (W) and
Y is CH and Z is nitrogen or wherein R.sub.6 is a radical of
formula (W), R.sub.7 is a hydrogen and Y is nitrogen and Z is CH.
These compounds are represented by the formulae (1) and (2)
respectively, wherein R, R.sub.1, R.sub.2, R.sub.3, R.sub.4, A, X,
m, n, and p have the meanings defined for compounds of formula
(I).
##STR00016##
[0030] A preferred class of compounds of formula (I) is that
wherein A is C(O).
[0031] Another preferred class of compounds of formula (I) is that
wherein X is CH.sub.2.
[0032] A further preferred class of compounds of formula (I) is
that wherein p is 1.
[0033] When Y is CH and Z is Nitrogen, a preferred group of
compounds of formula (I) is that in which the carbon atom at the
2-position of the piperidine ring is in the .beta.
configuration.
[0034] When Y is CH and Z is Nitrogen, a further preferred group of
compounds of formula (I) is that in which the carbon atom at the
2-position of the piperidine ring and the carbon atom bearing the
group (W) are in the .beta. configuration.
[0035] A further preferred group of compounds of formula (I) is
that in which the carbon atom at the 2-position of the piperidine
ring and the carbon atom bearing the group (W) are in the syn
configuration.
[0036] When R represents halogen, this is suitably chlorine or more
preferably fluorine or when R is C.sub.1-4 alkyl, this is suitably
methyl or ethyl.
[0037] R is preferably a halogen (e.g. fluorine) and/or a C.sub.1-4
alkyl (e.g. methyl) group and m is preferably zero or an integer
from 1 to 2.
[0038] R.sub.1 is preferably a methyl group.
[0039] R.sub.2 is preferably a hydrogen atom or a methyl group.
[0040] R.sub.3 is preferably a hydrogen atom or a methyl group.
[0041] R.sub.4 is preferably a trifluoromethyl group or halogen
(e.g. chlorine).
[0042] A preferred class of compounds of formula (I) is that
wherein each R is independently a halogen (e.g. fluorine) or a
C.sub.1-4 alkyl (e.g. methyl) group, wherein m is 0, 1 or 2. More
preferably, m is 1 or 2. Within this class, those wherein R is at
the 2 and/or 4 position in the phenyl ring are particularly
preferred.
[0043] Compounds of formula (I), wherein each R.sub.4 is
independently trifluoromethyl group or halogen (e.g. chlorine), n
is 2, represent a preferred class of compounds and within this
class the groups R.sub.4 are preferably at the 3 and 5 position in
the phenyl ring.
[0044] A group of preferred compounds of formula (I) is that
wherein R.sub.6 is hydrogen, R.sub.7 is a radical of formula (W)
and Y is CH and Z is nitrogen or wherein R.sub.6 is a radical of
formula (W), R.sub.7 is a hydrogen and Y is nitrogen and Z is CH
and A is C(O).
[0045] A group of further preferred compounds of formula (I) is
that in which R.sub.6 is hydrogen, R.sub.7 is a radical of formula
(W) and Y is CH and Z is nitrogen or wherein R.sub.6 is a radical
of formula (W), R.sub.7 is a hydrogen and Y is nitrogen and Z is
CH; A is C(O) and X is CH.sub.2.
[0046] A group of further particularly preferred compounds of
formula (I) is that in which
R.sub.6 is hydrogen, R.sub.7 is a radical of formula (W) and Y is
CH and Z is nitrogen or wherein R.sub.6 is a radical of formula
(W), R.sub.7 is a hydrogen and Y is nitrogen and Z is CH;
A is C(O);
X is CH.sub.2;
[0047] R is independently a halogen (e.g. fluorine) or a C.sub.1-4
alkyl (e.g. methyl) group; R.sub.4 is a trifluoromethyl group; m is
1 or 2; n is 2; p is 1.
[0048] Preferred compounds according to the invention are: [0049]
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-py-
razin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide; [0050]
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-py-
razin-2-yl)-piperidine-1-carboxylic
acid[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide;
[0051]
1-(4-Fluoro-2-methyl-phenyl)-4-(6-oxo-hexahydro-pyrrolo[1,2-a]pyrazin-2-y-
l)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide; and enantiomers,
diastereoisomers pharmaceutically acceptable salts (e.g.
hydrochloride, methanesulphonate or maleate) and solvates
thereof.
[0052] Particular preferred compounds of the invention are: [0053]
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-ylypiperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide; [0054]
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-ylypiperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide; and
amorphous and crystalline forms thereof and pharmaceutically
acceptable salts (e.g. hydrochloride or maleate) and solvates
thereof.
[0055] Tachykinins are a family of peptides that share a common
carboxyl-terminal sequence (Phe-X-Gly-Leu-Met-NH2). They are
actively involved in the physiology of both lower and advanced
lifeforms. In mammalian lifeforms, the main tachykinins are
substance P (SP), Neurokinin A (NKA) and Neurokinin B (NKB) which
act as neurotransmitters and neuromodulators. Mammalian tachykinins
may contribute to the pathophysiology of a number of human
diseases.
[0056] Three types of tachykinins receptors have been identified,
namely NK1 (SP-preferring), NK2 (NKA-preferring) and NK3
(NKB-preferring) which are widely distributed throughout the
central nervous (CNS) and peripheral nervous system.
[0057] Particularly, the compounds of the invention are antagonists
of the NK1 receptor.
[0058] By virtue of their efficacy as tachykinins receptor
(especially NK1 receptor) antagonists, the compounds of the present
invention are particularly useful for the treatment of CNS
disorders and psychotic disorders, in particular in the treatment
or prevention of depressive states and/or in the treatment of
anxiety.
[0059] NK.sub.1-receptor binding affinity has been determined in
vitro by measuring the compounds' ability to displace
[3H]-substance P (SP) from recombinant human NK.sub.1 receptor
expressed in Chinese Hamster Ovary (CHO) cell membranes and from
gerbil and marmoset brain cortex homogenates.
[0060] Membrane preparation from hNK1-CHO cells were performed
essentially as described by Beattie et al. (Br. J. Pharmacol,
116:3149-3157, 1995).
[0061] hNK1-CHO cells were harvested in phosphate buffered saline
(PBS) containing 5 mM EDTA and centrifuged at 913 g for 8 min at
4.degree. C. Cells were then re-suspended in 10 volumes of
membrane-preparation buffer (HEPES 50 mM, pH 7.4, containing 0.1 mM
leupeptin, 40 .mu.g/ml bacitracin, 1 mM EDTA, 1 mM Pefabloc and 2
.mu.M pepstatin A) and homogenised. The suspension was centrifuged
at 48,000 g for 20 minutes at 4.degree. C. The final pellet was
re-suspended in 10 volumes of membrane preparation buffer and
re-homogenised. Suspensions of membrane were then frozen at
-80.degree. C. until required.
[0062] The assay volume of 200 .mu.l consisted of 2 .mu.l of DMSO
or increasing concentrations of test compound dissolved in DMSO (1
pM-1 .mu.M final concentration), 100 .mu.l of [3H]-SP (0.5 nM final
concentration), and 100 .mu.l of membrane suspension (8 .mu.g of
protein per well) in incubation buffer (containing 50 mM HEPES, pH
7.4, 3 mM MnCl2, and 0.02% BSA). The incubation was carried out at
room temperature for 40 min. Non-specific binding was defined by
the addition of cold SP (1 .mu.M). The reaction was stopped by
rapid filtration. Filters were washed 5 times with 200 .mu.l of
ice-cold 0.9% w/v NaCl, and radioactivity was counted in a
microplate scintillation counter. In each experiment, every
concentration of displacer was tested in duplicate.
[0063] Mongolian gerbil (60 g, Charles River) and common marmoset
(Callithrix jacchus, 300-400 g, GSK colony, Verona, Italy) brain
cortex homogenates were prepared as follows: fresh tissues were
weighed, crumbled and homogenised in 10 volumes of
membrane-preparation buffer. The homogenate was then centrifuged at
48,000 g for 20 minutes, and the pellet was washed once more by
resuspension in 10 volumes of membrane preparation buffer and
centrifugation at 48,000 g for 20 minutes. The final pellet was
re-suspended in 7-10 volumes of membrane preparation buffer and
subdivided in aliquots frozen at -80.degree. C. until use.
[0064] The assay volume of 400 .mu.l consisted of 100 .mu.l of
incubation buffer (containing 50 mM HEPES, pH 7.4, 3 mM MnCl2, and
0.02% BSA), 4 .mu.l of DMSO or increasing concentrations of test
compound dissolved in DMSO (1 pM-1 .mu.M final concentration), 100
.mu.l of [3H]-SP (0.5 nM-0.8 nM final concentration) in incubation
buffer and 200 .mu.l of membrane suspension (0.6 mg protein for
gerbil, and 0.8 mg protein for marmoset) in incubation buffer
containing 2 .mu.g/ml leupeptin, 20 .mu.g/ml bacitracin and 0.5
.mu.M phosphoramidon. The incubation proceeded at room temperature
for 60 min. Non-specific binding was defined by the addition of
cold SP (1 .mu.M). The reaction was stopped by rapid filtration.
Filters were washed 3 times with 1 ml ice cold wash buffer
(containing 50 mM HEPES, pH 7.4, and 3 mM MnCl2), and radioactivity
was counted in a liquid scintillation counter.
[0065] The potency of test compounds to inhibit SP or
GR73632-induced increase of [Ca2+]i in hNK1/CHO cells was
determined in functional experiments by using FLIPR (fluorimetric
imaging plate reader) technology.
[0066] hNK1/CHO cells were seeded at a density of 60,000 cells per
well and cultured overnight in Ham's F-12 medium supplemented with
10% (v/v) heat-inactivated foetal bovine serum and 2 mM glutamine.
The cells were then incubated for the labelling in the culture
medium containing the fluorescent calcium indicator Fluo-4 AM (2
.mu.M), the organic anions transport blocker probenecid (5 mM), and
HEPES (20 mM) for 30 min in a humidified atmosphere of 5% CO2.
After washing with Hanks' Balanced Salts Solution (HBSS) containing
20 mM HEPES and 2.5 mM probenecid, the cells were incubated for 60
min at 37 C in wash buffer containing 0.02% BSA either in the
absence (control) or in the presence of test compounds. The plates
were then placed into a FLIPR to monitor cell fluorescence (ex=488
nm, em=510-570 nm) before and after the addition of different
concentrations of SP or GR73632 in assay buffer. Experiments were
carried out by using a laser setting of 1.0 W and a 0.4 sec charge
coupled device (CCD) camera shutter speed.
[0067] Compounds of the invention have also been found to exhibit
anxiolytic activity in conventional tests. For example in marmoset
human threat test (Costal) et al., 1988).
[0068] The action of the compounds of the invention at the NK.sub.1
receptor may be determined by using conventional tests. Thus, the
ability to penetrate the central nervous system and to bind at the
NK.sub.1 receptor was demonstrated in vivo by their inhibitory
effect on the change in the behaviour induced by
intracerebroventricular applied substance P in the gerbil,
according to the gerbil foot tapping model as described by Rupniak
& Williams, Eur. J. of Pharmacol., 265, 179-183, 1994.
[0069] Compounds of the invention are useful in the treatment of
CNS disorders and psychotic disorders, in particular in the
treatment or prevention of depressive states and/or in the
treatment of anxiety as defined in, but not restricted to,
Diagnostic Statistical of Mental Disorder (DSM) IV edition edit by
American Psychiatric Association and International Classification
Diseases 10th revision (ICD10).
[0070] Thus, for example, depressive states include Major
Depressive Disorders (MDD), including bipolar depression, unipolar
depression, single or recurrent major depressive episodes,
recurrent brief depression, with or without psychotic features,
catatonic features, melancholic features including anorexia, weight
loss, atypical features, anxious depression, cyclothymic or
postpartum onset.
[0071] Other mood disorders encompassed within the term major
depressive disorders include dysthymic disorders with early or late
onset and with or without atypical features, neurotic depression,
post-traumatic stress disorders and social phobia; dementia of the
Alzheimer's type, with early or late onset, with depressed mood;
vascular dementia with depressed mood; mood disorders induced by
alcohol, amphetamines, cocaine, hallucinogens, inhalants, opioids,
phencyclidine, sedatives, hypnotics, anxiolytics and other
substances; schizoaffective disorder of the depressed type; and
adjustment disorder with depressed mood. Major depressive disorders
may also result from a general medical condition including, but not
limited to, myocardial infarction, diabetes, miscarriage or
abortion, etc.
[0072] The term anxiety includes anxiety disorders, such as panic
disorders with or without agoraphobia, agoraphobia, phobias, for
example, social phobias or agoraphobia, obsessive-compulsive
disorder, stress disorders including post-traumatic stress
disorders, generalised anxiety disorders, acute stress disorders
and mixed anxiety-depression disorders.
[0073] Compounds of the invention are useful as analgesics. In
particular, they are useful in the treatment of traumatic pain such
as postoperative pain; traumatic avulsion pain such as brachial
plexus; chronic pain such as arthritic pain such as occurring in
osteo-, rheumatoid or psoriatic arthritis; neuropathic pain such as
post-herpetic neuralgia, trigeminal neuralgia, segmental or
intercostal neuralgia, fibromyalgia, causalgia, peripheral
neuropathy, diabetic neuropathy, chemotherapy-induced neuropathy,
AIDS related neuropathy, occipital neuralgia, geniculate neuralgia,
glossopharyngeal neuralgia, reflex sympathetic dystrophy, phantom
limb pain; various forms of headache such as migraine, acute or
chronic tension headache, temporomandibular pain, maxillary sinus
pain, cluster headache; odontalgia; cancer pain; pain of visceral
origin; gastrointestinal pain; nerve entrapment pain; sport's
injury pain; dysmennorrhoea; menstrual pain; meningitis;
arachnoiditis; musculoskeletal pain; low back pain e.g. spinal
stenosis; prolapsed disc; sciatica; angina; ankylosing
spondyolitis; gout; burns; scar pain; itch and thalamic pain such
as post stroke thalamic pain.
[0074] Compounds of the invention are also useful in the treatment
of sleep disorders including dysomnia, insomnia, sleep apnea,
narcolepsy, and circadian ritmic disorders.
[0075] Compounds of the invention are also useful in the treatment
or prevention of the cognitive disorders. Cognitive disorders
include dementia, amnestic disorders and cognitive disorders not
otherwise specified.
[0076] Furthermore, compounds of the invention are also useful as
memory and/or cognition enhancers in healthy humans with no
cognitive and/or memory deficit.
[0077] Compounds of the invention are also useful in the treatment
of tolerance to and dependence on a number of substances. For
example, they are useful in the treatment of dependence on
nicotine, alcohol, caffeine, phencyclidine (phencyclidine like
compounds) or in the treatment of tolerance to and dependence on
opiates (e.g. cannabis, heroin, morphine) or benzodiazepines; in
the treatment of addiction to cocaine, sedative ipnotic,
amphetamine or amphetamine-related drugs (e.g. dextroamphetamine,
methylamphetamine) or a combination thereof.
[0078] Compounds of the invention are also useful as
anti-inflammatory agents. In particular, they are useful in the
treatment of inflammation in asthma, influenza, chronic bronchitis
and rheumatoid arthritis; in the treatment of inflammatory diseases
of the gastrointestinal tract such as Crohn's disease, ulcerative
colitis, inflammatory bowel disease and non-steroidal
anti-inflammatory drug induced damage; inflammatory diseases of the
skin such as herpes and eczema; inflammatory diseases of the
bladder such as cystitis and urge incontinence; and eye and dental
inflammation.
[0079] Compounds of the invention are also useful in the treatment
of allergic disorders, in particular allergic disorders of the skin
such as urticaria, and allergic disorders of the airways such as
rhinitis.
[0080] Compounds of the invention are also useful in the treatment
or prevention of schizophrenic disorders including paranoid
schizophrenia, disorganised schizophrenia, catatonic schizophrenia,
undifferentiated schizophrenia, residual schizophrenia.
[0081] Compounds of the invention are also useful in the treatment
of emesis, i.e. nausea, retching and vomiting. Emesis includes
acute emesis, delayed emesis and anticipatory emesis. The compounds
of the invention are useful in the treatment of emesis however
induced. For example, emesis may be induced by drugs such as cancer
chemotherapeutic agents such as alkylating agents, e.g.
cyclophosphamide, carmustine, lomustine and chlorambucil; cytotoxic
antibiotics, e.g. dactinomycin, doxorubicin, mitomycin-C and
bleomycin; anti-metabolites, e.g. cytarabine, methotrexate and
5-fluorouracil; vinca alkaloids, e.g. etoposide, vinblastine and
vincristine; and others such as cisplatin, dacarbazine,
procarbazine and hydroxyurea; and combinations thereof; radiation
sickness; radiation therapy, e.g. irradiation of the thorax or
abdomen, such as in the treatment of cancer; poisons; toxins such
as toxins caused by metabolic disorders or by infection, e.g.
gastritis, or released during bacterial or viral gastrointestinal
infection; pregnancy; vestibular disorders, such as motion
sickness, vertigo, dizziness and Meniere's disease; post-operative
sickness; gastrointestinal obstruction; reduced gastrointestinal
motility; visceral pain, e.g. myocardial infarction or peritonitis;
migraine; increased intercranial pressure; decreased intercranial
pressure (e.g. altitude sickness); opioid analgesics, such as
morphine; and gastro-oesophageal reflux disease (GERD) such as
erosive GERD and symptomatic GERD or non erosive GERD, acid
indigestion, over-indulgence of food or drink, acid stomach, sour
stomach, waterbrash/regurgitation, heartburn, such as episodic
heartburn, nocturnal heartburn, and meal-induced heartburn,
dyspepsia and functional dyspepsia.
[0082] Compounds of the invention are also useful in the treatment
of gastrointestinal disorders such as irritable bowel syndrome,
gastro-oesophageal reflux disease (GERD) such as erosive GERD and
symptomatic GERD or non erosive GERD, acid indigestion,
over-indulgence of food or drink, acid stomach, sour stomach,
waterbrash/regurgitation, heartburn, such as episodic heartburn,
nocturnal heartburn, and meal-induced heartburn, dyspepsia and
functional dyspepsia (such as ulcer-like dyspepsia,
dysmotility-like dyspepsia and unspecified dyspepsia) chronic
constipation; skin disorders such as psoriasis, pruritis and
sunburn; vasospastic diseases such as angina, vascular headache and
Reynaud's disease; cerebral ischeamia such as cerebral vasospasm
following subarachnoid haemorrhage; fibrosing and collagen diseases
such as scleroderma and eosinophilic fascioliasis; disorders
related to immune enhancement or suppression such as systemic lupus
erythematosus and rheumatic diseases such as fibrositis; and
cough.
[0083] The compounds of the invention are also useful in
premenstrual dysphoric disorder (PMDD), in chronic fatigue syndrome
and Multiple sclerosis.
[0084] Compounds of the invention have been found to exhibit
anxiolytic and antidepressant activity in conventional tests. For
example, in Guinea pig pups separation-induced vocalisations
(Molewijk et al., 1996).
[0085] Compounds of the invention are also useful in the treatment
of convulsions and epilepsy.
[0086] Compounds of the invention may be administered in
combination with other active substances such as 5HT3 antagonists,
serotonin agonists, selective serotonin reuptake inhibitors (SSRI),
noradrenaline re-uptake inhibitors (SNRI), tricyclic
antidepressants or dopaminergic antidepressants.
[0087] Suitable 5HT3 antagonists which may be used in combination
with the compounds of the inventions include for example
ondansetron, granisetron and metoclopramide.
[0088] Suitable serotonin agonists which may be used in combination
with the compounds of the invention include sumatriptan,
rauwolscine, yohimbine and metoclopramide.
[0089] Suitable SSRI which may be used in combination with the
compounds of the invention include fluoxetine, citalopram,
femoxetine, fluvoxamine, paroxetine, indalpine, sertraline and
zimeldine.
[0090] Suitable SNRI which may be used in combination with the
compounds of the invention include venlafaxine and reboxetine.
[0091] Suitable tricyclic antidepressants which may be used in
combination with a compound of the invention include imipramine,
amitriptiline, chlomipramine and nortriptiline.
[0092] Suitable dopaminergic antidepressants which may be used in
combination with a compound of the invention include bupropion and
amineptine.
[0093] It will be appreciated that the compounds of the combination
may be administered simultaneously (either in the same or different
pharmaceutical formulations) or sequentially.
[0094] The invention therefore provides a compound of formula (I)
or a pharmaceutically acceptable salt or solvate thereof for use in
therapy, in particular in human medicine.
[0095] There is also provided as a further aspect of the invention
the use of a compound of formula (I) or a pharmaceutically
acceptable salt or solvate thereof in the preparation of a
medicament for use in the treatment of conditions mediated by
tachykinins, including substance P and other neurokinins.
[0096] In a further aspect of the invention there is provided the
use of a compound of formula (I) or a pharmaceutically acceptable
salt or solvate thereof in the treatment of conditions mediated by
tachykinins, including substance P and other neurokinins.
[0097] In an alternative or further aspect there is provided a
method for the treatment of a mammal, including man, in particular
in the treatment of conditions mediated by tachykinins, including
substance P and other neurokinins, comprising administration of an
effective amount of a compound of formula (I) or a pharmaceutically
acceptable salt thereof.
[0098] It will be appreciated that reference to treatment is
intended to include prophylaxis as well as the alleviation of
established symptoms. Compounds of formula (I) may be administered
as the raw chemical but the active ingredient is preferably
presented as a pharmaceutical formulation.
[0099] Accordingly, the invention also provides a pharmaceutical
composition which comprises at least one compound of formula (I) or
a pharmaceutically acceptable salt thereof and formulated for
administration by any convenient route. Such compositions are
preferably in a form adapted for use in medicine, in particular
human medicine, and can conveniently be formulated in a
conventional manner using one or more pharmaceutically acceptable
carriers or excipients.
[0100] Thus, compounds of formula (I) may be formulated for oral,
buccal, parenteral, topical (including ophthalmic and nasal), depot
or rectal administration or in a form suitable for administration
by inhalation or insufflation (either through the mouth or
nose).
[0101] For oral administration, the pharmaceutical compositions may
take the form of, for example, tablets or capsules prepared by
conventional means with pharmaceutically acceptable excipients such
as binding agents (e.g. pregelatinised maize starch,
polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers
(e.g. lactose, microcrystalline cellulose or calcium hydrogen
phosphate); lubricants (e.g. magnesium stearate, talc or silica);
disintegrants (e.g. potato starch or sodium starch glycollate); or
wetting agents (e.g. sodium lauryl sulphate). The tablets may be
coated by methods well known in the art. Liquid preparations for
oral administration may take the form of, for example, solutions,
syrups or suspensions, or they may be presented as a dry product
for constitution with water or other suitable vehicle before use.
Such liquid preparations may be prepared by conventional means with
pharmaceutically acceptable additives such as suspending agents
(e.g. sorbitol syrup, cellulose derivatives or hydrogenated edible
fats); emulsifying agents (e.g. lecithin or acacia); non-aqueous
vehicles (e.g. almond oil, oily esters, ethyl alcohol or
fractionated vegetable oils); and preservatives (e.g. methyl or
propyl-p-hydroxybenzoates or sorbic acid). The preparations may
also contain buffer salts, flavouring, colouring and sweetening
agents as appropriate.
[0102] Preparations for oral administration may be suitably
formulated to give controlled release of the active compound.
[0103] For buccal administration the composition may take the form
of tablets or lozenges formulated in conventional manner.
[0104] The compounds of the invention may be formulated for
parenteral administration by bolus injection or continuous
infusion. Formulations for injection may be presented in unit
dosage form e.g. in ampoules or in multi-dose containers, with an
added preservative. The compositions may take such forms as
suspensions, solutions or emulsions in oily or aqueous vehicles,
and may contain formulatory agents such as suspending, stabilising
and/or dispersing agents. Alternatively, the active ingredient may
be in powder form for constitution with a suitable vehicle, e.g.
sterile pyrogen-free water, before use.
[0105] The compounds of the invention may be formulated for topical
administration in the form of ointments, creams, gels, lotions,
pessaries, aerosols or drops (e.g. eye, ear or nose drops).
Ointments and creams may, for example, be formulated with an
aqueous or oily base with the addition of suitable thickening
and/or gelling agents. Ointments for administration to the eye may
be manufactured in a sterile manner using sterilised
components.
[0106] Lotions may be formulated with an aqueous or oily base and
will in general also contain one or more emulsifying agents,
stabilising agents, dispersing agents, suspending agents,
thickening agents, or colouring agents. Drops may be formulated
with an aqueous or non-aqueous base also comprising one or more
dispersing agents, stabilising agents, solubilising agents or
suspending agents. They may also contain a preservative.
[0107] The compounds of the invention may also be formulated in
rectal compositions such as suppositories or retention enemas, e.g.
containing conventional suppository bases such as cocoa butter or
other glycerides.
[0108] The compounds of the invention may also be formulated as
depot preparations. Such long acting formulations may be
administered by implantation (for example subcutaneously or
intramuscularly) or by intramuscular injection. Thus, for example,
the compounds of the invention may be formulated with suitable
polymeric or hydrophobic materials (for example as an emulsion in
an acceptable oil) or ion exchange resins, or as sparingly soluble
derivatives, for example, as a sparingly soluble salt.
[0109] For intranasal administration, the compounds of the
invention may be formulated as solutions for administration via a
suitable metered or unitary dose device or alternatively as a
powder mix with a suitable carrier for administration using a
suitable delivery device.
[0110] A proposed dose of the compounds of the invention is 1 to
about 1000 mg per day. It will be appreciated that it may be
necessary to make routine variations to the dosage, depending on
the age and condition of the patient and the precise dosage will be
ultimately at the discretion of the attendant physician or
veterinarian. The dosage will also depend on the route of
administration and the particular compound selected.
[0111] Compounds of formula (I), and salts and solvates thereof,
may be prepared by the general methods outlined hereinafter. In the
following description, the groups X, Y, Z, A, R, R.sub.1, R.sub.2,
R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, m, n and p, have the
meaning as previously defined for compounds of formula (I) unless
otherwise stated.
[0112] Compounds of formula (I) may be prepared by reductive
N-alkylation of a compound of formula (II), wherein R.sub.8 is
.dbd.O and R.sub.9 is hydrogen or R.sub.8 is hydrogen and R.sub.9
is .dbd.O
##STR00017##
with diazabicycle derivatives (III) or salts thereof. The reaction
is conveniently carried out in an aprotic solvent such as
dichloroethane and in the presence of a suitable metal reducing
agent such as sodium borohydride or sodium
triacetoxyborohydride.
[0113] In a further embodiment of the invention, compounds of
formula (I), wherein Y is CH, Z is nitrogen may be prepared by
reaction of a compound of formula (IV)
##STR00018##
with triphosgene or S(O)pCl wherein p is an integer from 1 to 2 in
an aprotic solvent such as dichloromethane and in the presence of
an organic base such triethylamine to form the intermediate
compound (V) in which A is C(O) or S(O)p respectively which may be
isolated if required, followed by reaction of compound (V) with the
amine compound (VI)
##STR00019##
[0114] The reaction conveniently takes place in an aprotic solvent
such as a hydrocarbon, a halohydrocarbon such as dichloromethane or
an ether such as tetrahydrofuran optionally in the presence of a
base such as a tertiary amine e.g. diisopropylethylamine.
[0115] In a further embodiment of the invention, compounds of
formula (I) wherein Y is nitrogen and Z is CH may be prepared by
reaction of an activated derivative of the carboxylic acid of
formula (VII), with amine (VI) or salts thereof, optionally in the
presence of a suitable base.
##STR00020##
[0116] Suitable activated derivatives of the carboxyl group include
the corresponding acyl halide, mixed anhydride, activated ester
such as a thioester or a derivative formed between the carboxylic
acid group and a coupling agent such as that used in peptide
chemistry, for example
O-(benzotriazol-1-yl)-N,N,N'N'-tetramethyluronium
tetrafluoroborate.
[0117] The reaction is preferably carried out in an aprotic solvent
such as an ether, e.g. tetrahydrofuran, a halohydrocarbon, e.g.
dichloromethane, N,N-dimethylformamide or acetonitrile.
[0118] Suitable base for use in this reaction include organic base
such as triethylamine or N,N diisopropylethylamine.
[0119] The activated derivatives of the carboxylic acid (VII) may
be prepared by conventional means. A particularly suitable
activated derivative for use in this reaction is obtained by
reaction of the carboxylic acid (II) with
O-(benzotriazol-1-yl)-N,N,N'N'-tetramethyluronium tetrafluoroborate
in a suitable aprotic solvent such as an ether e.g.
tetrahydrofuran, a halohydrocarbon e.g. dichloromethane, an amide
e.g. N,N-dimethylformamide or acetonitrile.
[0120] Compounds of formula (II), in which Y is CH, Z is nitrogen
may be prepared by treating compounds of formula (VIII), wherein
R.sub.8 and R.sub.9 have the meanings defined for compounds of
formula (II) and Ra is a nitrogen protecting group,
##STR00021##
using, after removal of Ra, the same procedures described above for
the preparation of compounds of formula (I) from compounds of
formula (IV).
[0121] Compounds of formula (II), wherein R.sub.8 and R.sub.9 have
the meanings defined for compounds of formula (II) and in which Y
is nitrogen, Z is CH, may be prepared by treating compounds of
formula (IX)
##STR00022##
using the same procedures described above for the preparation of
compounds of formula (II) from compounds of formula (VII).
[0122] Compounds of formulae (IV) and (VII) may be prepared by
reductive N-alkylation of a piperidine of formula (VIII) and a
carboxylic acid (IX) or esters thereof (such as methyl, ethyl and
the like) respectively with a diazabicycle derivatives (III) or
salts thereof. The reaction is conveniently carried out in an
aprotic solvent such as dichloroethane and in the presence of a
suitable metal reducing agent such as sodium borohydride or sodium
triacetoxyborohydride.
[0123] Examples of suitable nitrogen protecting groups Ra include
alkoxycarbonyl e.g. t-butoxycarbonyl, benzyloxycarbonyl,
arylsulphonyl e.g. phenysulphonyl or
2-trimethylsilylethoxymethyl.
[0124] Protection and deprotection may be effected using
conventional techniques such as those described in "Protective
Groups in Organic Synthesis 2.sup.nd Ed." by T. W. Greene and P. G.
M. Wuts (John Wiley and Sons, 1991) and as described in the
examples hereinafter
[0125] Compounds of formula (VIII) are either known compounds or
may be prepared by analogous methods to those used for known
compounds.
[0126] Thus, for example, compound (VIII) and enantiomers thereof
may be prepared using Comins reaction as described in Journal
American Chemical Society 1994, 116, 4719-4728, followed by
reduction of 2,3 dihydro-1H-pyridin-4-one derivative to
piperidine-4-one derivative. The reduction may be effected using
hydrogen and metal catalyst e.g. palladium on a suitable support
e.g. carbon or alumina. The reaction is carried out in a solvent
such as ester e.g. ethyl acetate.
[0127] Compounds of formula (IX) wherein R.sub.8 is .dbd.O and
R.sub.9 is hydrogen are known compounds and they may be prepared
according to the procedures as described in Bioorganic &
Medicinal Chemistry Letters, Vol 2, No 11, pp 1357-1360, 1992.
[0128] Compounds of formula (IX) wherein R.sub.9 is .dbd.O and
R.sub.8 is hydrogen are novel compounds and they may be prepared
for example by reaction of an amine (XIV) with ethyl glyoxalate to
obtain the intermediates (XIII) which may be converted into
4-oxo-tetrahydropyridine intermediates (XII) which in turn may be
reduced to an intermediate of formula (XI). Said intermediate (XI)
may be in turn hydrolysed, thus forming an intermediate of formula
(IX).
##STR00023##
[0129] It will be appreciated by those skilled in the art that the
compounds of formula (III) contain one chiral center (namely the
carbon atom shown as * in the formulae IIIa and IIIb).
##STR00024##
[0130] It is to be understood that the reference to compounds of
formula (III) includes all stereoisomeric forms and all mixtures
thereof.
[0131] Compounds of formula (III) are known compounds or may be
prepared by analogous methods to those used for known
compounds.
[0132] Thus, compounds of formula (III) wherein X is CH.sub.2 and p
is 1 may be prepared as described in Bioorganic & Medicinal
Chemistry Letters, (1998) pages 3469-3474; or in Journal of
Medicinal Chemistry, 2000 Vol 43 No 10 pages 1969-1974.
[0133] Thus, in a particular embodiment of the invention, compounds
of formula (III), wherein X is CH.sub.2 and p is 1, may be prepared
by reacting 2-methylpyrazine (XV) with a tert-butyhaloacetate such
as for example tert-butylbromoacetate in the presence of a suitable
base such as for example lithium diisopropylamine in an aprotic
solvent such as tetrahydrofuran and at a temperature around
-78.degree. to obtain compound (XVI) which in turn may be converted
into compound (XVII), wherein R.sub.10 is methyl or ethyl, by
reaction with sodium ethylate or with hydrochloride in methanol.
Said compound may be subsequently reduced and cyclized to obtain
compound (III). The reduction may be carried out by heating and
using hydrogen and a metal catalyst e.g palladium.
##STR00025##
[0134] Where it is desired to isolate a compound formula (I) as a
salt, for example a pharmaceutically acceptable salt, this may be
achieved by reacting the compound of formula (I) in the form of the
free base with an appropriate amount of suitable acid and in a
suitable solvent such as an alcohol (e.g. ethanol or methanol), an
ester (e.g. ethyl acetate) or an ether (e.g. diethyl ether or
tetrahydrofuran).
[0135] Pharmaceutically acceptable salts may also be prepared from
other salts, including other pharmaceutically acceptable salts, of
the compounds of formula (I) using conventional methods.
[0136] The compounds of formula (I) may readily be isolated in
association with solvent molecules by crystallisation from or
evaporation of an appropriate solvent to give the corresponding
solvates.
[0137] When a specific enantiomer of a compound of general formula
(I) is required, this may be obtained for example by resolution of
a corresponding enantiomeric mixture of a compound of formula (I)
using conventional methods.
[0138] Thus, for example, specific enantiomers of the compounds of
formula (I) may be obtained from the corresponding enantiomeric
mixture of a compound of formula (I) using chiral HPLC
procedure.
[0139] Alternatively, enantiomers of a compound of general formula
(I) may be synthesised from the appropriate optically active
intermediates (III), (IV), (V), (VII), (VIII) and (IX) using any of
the general processes described herein.
[0140] Thus, for example, the chiral compounds (III), (IV) and
(VIII) may be prepared from the corresponding racemic compounds
(III), (IV) and (VIII) using conventional procedures such as salt
formation with a suitable optically active acid.
[0141] Suitable optically active acid for use in the process is
L(+)mandelic acid or S)-(+)-O-acetylmandelic acid.
[0142] The chiral compounds (VII) and (IX) may be prepared from the
corresponding racemic compounds (VII) and (IX) using conventional
procedures such as salt formation with a suitable optically active
amine.
[0143] Said diastereoisomeric salt forms are subsequently separated
by conventional means e.g. chromatography and crystallisation and
the enantiomers are subsequently liberated by hydrolysis of the
diastereoisomeric salts.
[0144] The invention is further illustrated by the following
Intermediates and Examples which are not intended as a limitation
of the invention.
[0145] In the Intermediates and Examples unless otherwise
stated:
[0146] Melting points (m.p.) were determined on a Buchi m.p.
apparatus and are uncorrected. R.T. or r.t. refer to room
temperature.
[0147] Infrared spectra (IR) were measures in chloroform or nujol
solutions on a FT-IR instrument. Proton Magnetic Resonance (NMR)
spectra were recorded on Varian instruments at 400 or 500 MHz,
chemical shifts are reported in ppm (.delta.) using the residual
solvent line as internal standard. Splitting patterns are designed
as s, singlet; d, double; t, triple; q, quartet; m, multiplet; b,
broad.
[0148] Mass spectra (MS) were taken on a VG Quattro mass
spectrometer. Optical rotations were determined at 20.degree. C.
with a Jasco DIP360 instrument (I=10 cm, cell volume=1 mL,
.lamda.=589 nm). Flash silica gel chromatography was carried out
over silica gel 230-400 mesh supplied by Merck AG Darmstadt,
Germany. T.l.c. refers to thin layer chromatography on 0.25 mm
silica gel plates (60F-254 Merck) and visualized with UV light.
[0149] Solutions were dried over anhydrous sodium sulphate.
[0150] Methylene chloride was redistilled over calcium hydride and
tetrahydrofuran was redistilled over sodium.
[0151] The following abbreviation are used in the text: AcOEt=ethyl
acetate, CH=cyclohexane, DCM=methylene chloride,
DIPEA=N,N-diisopropylethylamine, DMF=N,N'-dimethylformamide,
Et2O=diethyl ether, EtOH=ethanol, MeOH=methanol TEA=triethylamine,
THF=tetrahydrofuran.
[0152] The X-ray powder diffraction pattern of a crystalline form
of the compound of the invention was obtained by loading the sample
into the diffractometer (Siemens D5005 X-ray diffractometer
equipped with .theta./.theta. goniometer, scintillation counter and
graphite monochromator. The diffractometer was set up with the
instrumental parameters given below.
Instrumental Parameters
[0153] MONOCHROMATIC RADIATION: Cu--1.54056/1.54439
2 RANGE: 2.degree.-40.degree. 2
[0154] GENERATOR VOLTAGE/CURRENT: 40 kV/50 mA
STEP SIZE: 0.04.degree. 2
[0155] TIME PER STEP: 2 sec.sup.-1
ROTATION: Off
[0156] DIVERGENCE/ANTISCATTERING SLIT: variable (fixed area) SAMPLE
HOLDER: TTK sample holder (Alan Paar instruments)
TEMPERATURE: 25.degree. C.
[0157] The spectrum obtained was analysed using the data evaluation
software EVA3.0.
Intermediate 1
1-(Benzyloxycarbonyl)-2-(4-fluoro-2-methyl-phenyl)-2,3-dihydro-4-pyridone
[0158] A small amount of iodine was added to a suspension of
magnesium turnings (13.2 g) in dry THF (300 mL), at r.t., under a
nitrogen atmosphere, then the mixture was vigorously refluxed for
20 minutes. To this suspension, a 15% of a solution of
2-bromo-5-fluoro-toluene (52.5 mL) in anhydrous THF (300 mL) was
added. The suspension was heated under vigorous reflux until the
brown colour disappeared. The remaining part of the bromide
solution was added drop-wise over 1 hour to the refluxing
suspension which was then stirred for a further 1 hour. This
solution of Grignard reagent was then added drop-wise to the
pyridinium salt obtained from benzyl chloroformate (48.7 mL) and
4-methoxypyridine (25 mL) in dry THF (900 mL) at -23.degree. C.
[0159] The obtained solution was stirred 1 hour at -20.degree. C.
then it was warmed up to 20.degree. C., a 10% hydrochloric acid
solution (560 mL) was added and the aqueous layer was extracted
with AcOEt (2.times.750 mL).
[0160] The combined organic extracts were washed with 5% sodium
hydrogen carbonate solution (600 mL) and brine (600 mL) then
partially concentrated in vacuo.
[0161] CH (400 mL) was added drop-wise over 1 hour at 20.degree. C.
and the resulting mixture was stirred 30 minutes and then filtered
to give the title compound as a white solid (66 g).
[0162] IR (nujol, cm.sup.-1): 1726 and 1655 (C.dbd.O), 1608
(C.dbd.C).
[0163] NMR (d.sub.6-DMSO): .delta. (ppm) 8.19 (d, 1H); 7.31-7.18
(m, 5H); 7.08 (m, 2H); 6.94 (dt, 1H); 5.77 (d, 1H); 5.36 (d, 1H);
5.16 (2d, 2H); 3.26 (dd, 1H); 2.32 (d, 1H); 2.26 (s, 3H).
[0164] MS (ES/+): m/z=340 [MH].sup.+.
Intermediate 2
2-(4-Fluoro-2-methyl-phenyl)-piperidine-4-one
Method A:
[0165] 4-Fluoro-2-methyl-benzaldehyde (4 g) was added to a solution
of 4-aminobutan-2-one ethylene acetal (3.8 g) in dry benzene (50
mL) and the solution was stirred at r.t. under a nitrogen
atmosphere. After 1 hour the mixture was heated at reflux for 16
hours and then allowed to cool to r.t. This solution was slowly
added to a refluxing solution of p-toluenesulphonic acid (10.6 g)
in dry benzene (50 mL) previously refluxed for 1 hour with a
Dean-Stark apparatus. After 3.5 hours the crude solution was cooled
and made basic with a saturated potassium carbonate solution and
taken up with AcOEt (50 mL). The aqueous phase was extracted with
AcOEt (3.times.50 mL) and Et2O (2.times.50 mL). The organic layer
was dried and concentrated in vacuo to a yellow thick oil as
residue (7.23 g). A portion of the crude mixture (3 g) was
dissolved in a 6N hydrochloric acid solution (20 mL) and stirred at
60.degree. C. for 16 hours. The solution was basified with solid
potassium carbonate and extracted with DCM (5.times.50 mL). The
combined organic phases were washed with brine (50 mL), dried and
concentrated in vacuo to give the title compound (2.5 g) as a thick
yellow oil.
Method B
[0166] L-selectride (1M solution in dry THF, 210 mL) was added
drop-wise, over 80 minutes, to a solution of intermediate 1 (50 g)
in dry THF (1065 mL) previously cooled to -72.degree. C. under a
nitrogen atmosphere. After 45 minutes, 2% sodium hydrogen carbonate
solution (994 mL) was added drop-wise and the solution was
extracted with AcOEt (3.times.994 mL). The combined organic phases
were washed with water (284 mL) and brine (568 mL). The organic
phase was dried and concentrated in vacuo to get
1-benzyloxycarbonyl-2-(4-fluoro-2-methyl-phenyl)-piperidine-4-one
as a pale yellow thick oil (94 g) which was used as a crude.
[0167] This material (94 g) was dissolved in AcOEt (710 mL), then
10% Pd/C (30.5 g) was added under a nitrogen atmosphere. The slurry
was hydrogenated at 1 atmosphere for 30 minutes. The mixture was
filtered through Celite and the organic phase was concentrated in
vacuo to give the crude
2-(4-fluoro-2-methyl-phenyl)-piperidine-4-one as a yellow oil. This
material was dissolved in AcOEt (518 mL) at r.t. and racemic
camphorsulphonic acid (48.3 g) was added. The mixture was stirred
at r.t for 18 hours, then the solid was filtered off, washed with
AcOEt (2.times.50 mL) and dried in vacuo for 18 hours to give
2-(4-fluoro-2-methyl-phenyl)-piperidine-4-one, 10-camphorsulfonic
acid salt as a pale yellow solid (68.5 g). (M.p.: 167-169.degree.
C.--NMR (d.sub.6-DMSO): .delta. (ppm) 9.43 (bs, 1H); 9.23 (bs, 1H);
7.66 (dd, 1H); 7.19 (m, 2H); 4.97 (bd, 1H); 3.6 (m, 2H); 2.87 (m,
3H); 2.66 (m, 1H); 2.53 (m, 2H); 2.37 (s+d, 4H); 2.22 (m, 1H); 1.93
(t, 1H); 1.8 (m, 2H); 1.26 (m, 2H); 1.03 (s, 3H); 0.73 (s, 3H).
[0168] This material (68.5 g) was suspended in AcOEt (480 mL) and
stirred with a saturated sodium hydrogen carbonate (274 mL). The
organic layer was separated and washed with further water (274 mL).
The organic phase was dried and concentrated in vacuo to give the
title compound (31 g) as a yellow-orange oil.
[0169] NMR (d.sub.6-DMSO): .delta. (ppm) 7.49 (dd, 1H); 7.00 (m,
2H); 3.97 (dd, 1H); 3.27 (m, 1H); 2.82 (dt, 1H); 2.72 (bm, 1H);
2.47 (m, 1H); 2.40 (m, 1H); 2.29 (s, 3H); 2.25 (dt, 1H); 2.18 (m,
1H).
[0170] MS (ES/+): m/z=208 [MH].sup.+.
Intermediate 3
2-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide
[0171] A solution of triphosgene (1.43 g) dissolved in dry DCM (10
mL) was added to a solution of intermediate 2 (2.5 g) and DIPEA
(8.4 mL) in dry DCM (20 mL) previously cooled to 0.degree. C. under
a nitrogen atmosphere. The solution was stirred at 0.degree. C. for
2 hours, then (3,5-bis-trifluoromethyl-benzyl)-methylamine
hydrochloride (5.63 g) and DIPEA (3.34 mL) were added. The mixture
was stirred under nitrogen at r.t. for 14 hours. The mixture was
taken up with AcOEt (50 mL), washed with cold 1N hydrochloric acid
solution (3.times.20 mL) and brine (10 mL). The organic layer was
dried and concentrated in vacuo to a residue which was purified by
flash chromatography (AcOEt/CH 3:7) to give the title compound as a
white foam (3.85 g).
[0172] IR (nujol, cm.sup.-1): 1721 and 1641 (C.dbd.O).
[0173] NMR (d.sub.6-DMSO): .delta. (ppm) 7.96 (s, 1H); 7.76 (s,
2H); 7.25 (dd, 1H); 6.97 (dd, 1H); 6.90 (dt, 1H); 5.22 (t, 1H);
4.59 (d, 1H); 4.43 (d, 1H); 3.63-3.49 (m, 2H); 2.79 (s, 3H); 2.69
(m, 2H); 2.49 (m, 2H); 2.26 (s, 3H).
[0174] MS (ES/+): m/z=491 [MH].sup.+.
Intermediate 4
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
[1-(R)-3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (4a) and
2-(S)-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
[1-(R)-3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (4b)
Method A:
[0175] A solution of triphosgene (147 mg) dissolved in dry DCM (5
mL) was added drop-wise to a solution of intermediate 2 (250 mg)
and DIPEA (860 .mu.L) in dry DCM (15 mL) previously cooled to
0.degree. C. under a nitrogen atmosphere. After 2 hours,
[1-(R)-3,5-bis-trifluoromethyl-phenyl)ethyl]-methylamine
hydrochloride (503 mg) and DIPEA (320 .mu.L) in dry acetonitrile
(20 mL) were added and the mixture was heated to 70.degree. C. for
16 hours. Further
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamine
hydrochloride (170 mg) and DIPEA (100 .mu.L) were added and the
mixture was stirred at 70.degree. C. for further 4 hours. Next, the
mixture was allowed to cool to r.t., taken up with AcOEt (30 mL),
washed with a 1N hydrochloric acid cold solution (3.times.15 mL)
and brine (2.times.10 mL). The organic layer was dried and
concentrated in vacuo to a residue, which was purified by flash
chromatography (CH/AcOEt 8:2) to give:
[0176] 1. intermediate 4a (230 mg) as a white foam,
[0177] 2. intermediate 4b (231 mg) as a white foam.
Intermediate 4a
[0178] NMR (d.sub.6-DMSO): .delta. (ppm) 7.98 (bs, 1H); 7.77 (bs,
2H); 7.24 (dd, 1H); 6.97 (dd, 1H); 6.89 (m, 1H); 5.24 (t, 1H); 5.14
(q, 1H); 3.61 (m, 1H); 3.55 (m, 1H); 2.71 (m, 2H); 2.56 (s, 3H);
2.50 (m, 2H); 2.26 (s, 3H); 1.57 (d, 3H).
Intermediate 4b
[0179] NMR (d.sub.6-DMSO): .delta. (ppm) 7.96 (bs, 1H); 7.75 (bs,
2H); 7.24 (dd, 1H); 6.98 (dd, 1H); 6.93 (dt, 1H); 5.29 (q, 1H);
5.24 (t, 1H); 3.56 (m, 1H); 3.48 (m, 1H); 2.70 (s, 3H); 2.50 (m,
4H); 2.26 (s, 3H); 1.54 (d, 3H).
Intermediate 4a
Method B
[0180] A saturated sodium hydrogen carbonate solution (324 mL) was
added to a solution of intermediate 9 (21.6 g) in AcOEt (324 mL)
and the resulting mixture was vigorously stirred for 15 minutes.
The aqueous layer was back-extracted with further AcOEt (216 mL)
and the combined organic extracts were dried and concentrated in
vacuo to give intermediate 8 as a yellow oil, which was treated
with TEA (19 mL) and AcOEt (114 mL). The solution obtained was
added drop-wise over 40 minutes to a solution of triphosgene (8 g)
in AcOEt (64 mL) previously cooled to 0.degree. C. under a nitrogen
atmosphere, maintaining the temperature between 0.degree. C. and
8.degree. C. After stirring for 1 hours at 0.degree. C. and for 3
hours at 20.degree. C.,
[1-(R)-(3,5-bis-trifluoromethylphenyl)-ethyl]-methylamine
hydrochloride (29.7 g), AcOEt (190 mL) and TEA (38 mL) were added
to the reaction mixture which was then heated to reflux for 16
hours.
[0181] The solution was washed with 10% sodium hydroxide solution
(180 mL), 1% hydrochloric acid solution (4.times.150 mL), water
(3.times.180 mL) and brine (180 mL). The organic layer was dried
and concentrated in vacuo to a residue, which was purified through
a silica pad (CH/AcOEt 9:1) to give the title compound (21.5 g) as
a brown thick oil.
[0182] NMR (d.sub.6-DMSO): .delta. (ppm) 7.97-7.77 (bs+bs, 3H);
7.24 (dd, 1H); 6.97 (dd, 1H); 6.88 (td, 1H); 5.24 (m, 1H); 5.14 (q,
1H); 3.58 (m, 2H); 2.7 (m, 2H); 2.56 (s, 3H); 2.49 (m, 2H); 2.26
(s, 3H); 1.57 (d, 3H).
Intermediate 5
2-(S)-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (5a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (5b)
[0183] A solution of triphosgene (147 mg) dissolved in dry DCM (5
mL) was added to a solution of intermediate 2 (250 mg) and DIPEA
(860 .mu.L) in dry DCM (15 mL) previously cooled to 0.degree. C.
under a nitrogen atmosphere. After 2 hours, a solution of
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)ethyl]-methylamine
hydrochloride (510 mg) and DIPEA (320 .mu.L) in dry acetonitrile
(20 mL) was added and the mixture was heated to 70.degree. C. for
16 hours. Next, further
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamine
hydrochloride (170 mg) and DIPEA (105 .mu.L) were added. After
further 4 hours at 70.degree. C., the mixture was allowed to cool
to r.t., taken up with AcOEt (30 mL), washed with a 1N hydrochloric
acid cold solution (3.times.15 mL) and brine (2.times.10 mL). The
organic layer was dried and concentrated in vacuo to a residue,
which was purified by flash chromatography (CH/AcOEt 8:2) to
give:
[0184] 1. intermediate 5a (234 mg) as a white foam,
[0185] 2. intermediate 5b (244 mg) as a white foam.
Intermediate 5a
[0186] NMR (d.sub.6-DMSO): .delta. (ppm) 7.97-7.77 (bs+bs, 3H);
7.24 (dd, 1H); 6.97 (dd, 1H); 6.88 (td, 1H); 5.24 (m, 1H); 5.14 (q,
1H); 3.58 (m, 2H); 2.7 (m, 2H); 2.56 (s, 3H); 2.49 (m, 2H); 2.26
(s, 3H); 1.57 (d, 3H).
Intermediate 5b
[0187] NMR (d.sub.6-DMSO): .delta. (ppm) 7.98 (bs, 1H); 7.77 (bs,
2H); 7.24 (dd, 1H); 6.97 (dd, 1H); 6.89 (m, 1H); 5.24 (t, 1H); 5.14
(q, 1H); 3.61 (m, 1H); 3.55 (m, 1H); 2.71 (m, 2H); 2.56 (s, 3H);
2.50 (m, 2H); 2.26 (s, 3H); 1.57 (d, 3H).
Intermediates 6
2-(S)-(4-Fluoro-2-methyl-phenyl)-4-oxo-3,4-dihydro-2H-pyridine-1-carboxyli-
c acid (1R,2S,5R)-2-isopropyl-5-methyl-cyclohexyl ester (6a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-oxo-3,4-dihydro-2H-pyridine-1-carboxyl-
ic acid (1R,2S,5R)-2-isopropyl-5-methyl-cyclohexyl ester (6b)
[0188] A solution of 2-bromo-5-fluoro-toluene (3.68 g) in dry THF
(10 mL) was dropped over 30 minutes, into a mixture of magnesium
(525 mg) and iodine (1 crystal) in dry THF (5 mL) previously heated
to 70.degree. C. under a nitrogen atmosphere. The mixture was
stirred at 70.degree. C. for 1.5 hours, then allowed to cool to
r.t.
[0189] A solution of (-)-mentyl chloroformate (3.53 mL) in dry THF
(15 mL) was added to a solution of 4-methoxypyridine (1.52 mL) in
dry THF (35 mL) previously cooled to -78.degree. C. under a
nitrogen atmosphere. After 15 minutes, the solution containing the
4-fluoro-2-methyl-phenyl magnesium bromide was added drop-wise, and
the mixture was stirred at -78.degree. C. for 1 hour. The reaction
was quenched by the addition of 1M hydrochloric acid solution (20
mL), warmed to r.t. and stirred at 23.degree. C. for 30 minutes.
After extraction with AcOEt (2.times.150 mL), the combined organic
extracts were washed with brine (50 mL), dried and concentrated in
vacuo to a residue, which was purified by flash chromatography
(CH/THF/toluene 8:1:1) to give:
[0190] 1. intermediate 6a (3.44 g--yellow oil)
[0191] 2. intermediate 6b (530 mg--white solid).
Intermediate 6a
[0192] T.l.c.: CH/THF/toluene 7:2:1, Rf=0.59.
[0193] IR (nujol, cm.sup.-1): 1718 and 1675 (C.dbd.O).
[0194] NMR (d.sub.6-DMSO): .delta. (ppm) 8.14 (d, 1H); 7.08 (dd,
1H); 7.02 (dd, 1H); 6.95 (m, 1H); 5.68 (d, 1H); 5.34 (d, 1H); 4.47
(m, 1H); 3.26 (dd, 1H); 2.30 (m, 4H); 1.7 (m, 4H); 1.33 (m, 2H);
0.8 (m, 11H).
Intermediate 6b
[0195] M.p.: 117-120.degree. C.
[0196] T.l.c.: CH/THF/toluene 7:2:1, Rf=0.56.
[0197] IR (nujol, cm.sup.-1): 1718 and 1669 (C.dbd.O).
[0198] NMR (d.sub.6-DMSO): .delta. (ppm) 8.17 (d, 1H); 7.04-6.94
(m, 3H); 5.70 (d, 1H); 5.35 (d, 1H); 4.42 (m, 1H); 3.26 (dd, 1H);
2.30 (m, 4H); 1.58-1.40 (m, 3H); 1.2-0.7 (m, 8H); 0.51-0.34 (bs,
6H):
Intermediate 7
2-(R)-(4-Fluoro-2-methyl-phenyl)-2,3-dihydro-1H-pyridin-4-one
[0199] Sodium methoxide (100 mg) was added to a solution of
intermediate 6b (170 mg) in MeOH (15 mL) under a nitrogen
atmosphere. The mixture was refluxed for two hours and the solvent
was removed in vacuo. The residue was partitioned between water (10
mL) and AcOEt (15 mL). The layers were separated, and the aqueous
phase was extracted with further AcOEt (4.times.10 mL). The
combined organic extracts were washed with brine (10 mL), dried and
concentrated in vacuo to give the title compound (145 mg) as a
light yellow oil.
[0200] NMR (d.sub.6-DMSO): .delta. (ppm) 7.71 (bd, 1H); 7.45 (dd,
1H); 7.38 (t, 1H); 7.03 (m, 2H); 4.86 (dd, 1H); 4.77 (d, 1H); 2.42
(dd, 1H); 2.31 (m, 4H).
[0201] MS (ES/+): m/z=206 [M+H].sup.+.
Intermediate 8
2-(R)-(4-Fluoro-2-methyl-phenyl)-piperidin-4-one
[0202] Palladium over charcoal (10%-74 mg) was added to a solution
of intermediate 7 (145 mg) in MeOH (8 mL) and THF (2 mL). The
mixture was allowed to react with hydrogen in a pressure reactor (2
atm) overnight. After flushing with nitrogen, the solution was
filtered and the solvent removed in vacuo. The crude product was
purified by flash chromatography (AcOEt/MeOH 9:1) to give the title
compound (26 mg) as a yellow oil.
[0203] The enantiomeric excess (90-95%) was detected by chiral
HPLC.
[0204] T.l.c.: AcOEt/MeOH 9:1, Rf=0.2.
[0205] NMR (d.sub.6-DMSO): .delta. (ppm) 7.49 (dd, 1H); 7.00 (m,
2H); 3.97 (dd, 1H); 3.27 (m, 1H); 2.82 (dt, 1H); 2.72 (bm, 1H);
2.47 (m, 1H); 2.40 (m, 1H); 2.29 (s, 3H); 2.25 (dt, 1H); 2.18 (m,
1H).
[0206] MS (ES/+): m/z=208 [MH].sup.+.
[0207] [.lamda.].sub.D=+82.1 (c=1.07, DMSO).
Intermediate 9
2-(R)-(4-Fluoro-2-methyl-phenyl)-piperidin-4-one
L-(+)-mandelate
[0208] A solution of L-(+)-mandelic acid (22.6 g) in AcOEt (308 mL)
was added to a solution of intermediate 2 (31 g) in AcOEt (308 mL).
Then isopropanol (616 mL) was added and the solution was
concentrated in vacuo to 274 mL. The solution was then cooled to
0.degree. C. and further cold isopropanol (96 mL) was added. The
thick precipitate was stirred under nitrogen for 5 hours at
0.degree. C., then filtered and washed with cold Et2O (250 mL) to
give the title compound as a pale yellow solid (20.3 g).
[0209] M.p.: 82-85.degree. C.
[0210] NMR (d.sub.6-DMSO): .delta. (ppm) 7.51 (dd, 1H); 7.40 (m,
2H); 7.32 (m, 2H); 7.26 (m, 1H); 7.0 (m, 2H); 4.95 (s, 1H); 4.04
(dd, 1H); 3.31 (m, 1H); 2.88 (m, 1H); 2.49-2.2 (m, 4H); 2.29 (s,
3H).
[0211] Chiral HPLC: HP 1100 HPLC system; column Chiralcel OD-H, 25
cm.times.4.6 mm; mobile phase: n-hexane/isopropanol 95:5+1%
diethylamine; flow: 1.3 ml/min; detection: 240/215 nm; retention
time 12.07 minutes.
Intermediate 10
2-(R)-4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide
Method A
[0212] A solution of triphosgene (17 mg) in dry DCM (2 mL) was
added to a solution of intermediate 8 (26 mg) and DIPEA (65 mg) in
dry DCM (3 mL) previously cooled to 0.degree. C. under a nitrogen
atmosphere. After two hours acetonitrile (10 mL) was added, the
temperature was allowed to reach r.t. and the DCM evaporated under
a nitrogen flush. Then, a solution of
3,5-(bis-trifluoromethyl-benzyl)-methylamine hydrochloride (74 mg)
and DIPEA (130 mg) in acetonitrile (3 mL) was added and the mixture
was stirred at 23.degree. C. overnight. The solvent was
concentrated in vacuo. The residue was dissolved in AcOEt (10 mL)
and washed with 1N hydrochloric acid solution (3.times.5 mL), 5%
sodium hydrogen carbonate (5 mL) and brine (10 mL). The organic
layer was dried and concentrated in vacuo to a residue, which was
purified by flash chromatography (CH/AcOEt 1:1) to give the title
compound (50 mg) as a white solid.
Method B
[0213] A saturated sodium hydrogen carbonate solution (348 mL) was
added to a solution of intermediate 9 (23.2 g) in AcOEt (348 mL)
and the resulting mixture was vigorously stirred for 15 minutes.
The aqueous layer was back-extracted with further AcOEt (230 mL)
and the combined organic extracts were dried and concentrated in
vacuo to give intermediate 8 (12.31 g) as a yellow oil, which was
treated with TEA (20.5 mL) and AcOEt (123 mL). The solution
obtained was added drop-wise over 40 minutes to a solution of
triphosgene (8 g) in AcOEt (61 mL) previously cooled to 0.degree.
C. under a nitrogen atmosphere, maintaining the temperature between
0.degree. C. and 8.degree. C.
[0214] After stirring for 2 hours at 20.degree. C.,
3,5-(bis-trifluoromethyl-benzyl)-methylamine hydrochloride (28.1
g), AcOEt (184 mL) and TEA (33 mL) were added to the reaction
mixture which was then further stirred for 2 hours at 20.degree. C.
The solution was washed with 10% sodium hydroxide solution
(3.times.185 mL) and 1% hydrochloric acid solution (3.times.185
mL). The organic layer was dried and concentrated in vacuo to a
crude (38 g), which was purified through a silica pad (CH/AcOEt
from 9:1 to 1:1) to give the title compound (24.7 g) as a
colourless oil.
[0215] NMR (d.sub.6-DMSO): .delta. (ppm) 7.96 (s, 1H); 7.76 (s,
2H); 7.26 (dd, 1H); 6.98 (dd, 1H); 6.90 (td, 1H); 5.23 (t, 1H);
4.61 (d, 1H); 4.41 (d, 1H); 3.60 (m, 2H); 2.69 (m, 2H); 2.79 (s,
3H); 2.50 (m, 2H); 2.27 (s, 3H).
[0216] MS (ES/+): m/z=491 [MH].sup.+.
Intermediate 11
1,4-Dibenzyl-2-piperazinecarboxaldehyde
[0217] A solution of ethyl 2,3-dibromopropionate (6 mL) in
anhydrous toluene (50 mL) was added to a solution of
N,N'-dibenzylethylenediamine (5 g) and DIPEA (12 mL) in anhydrous
toluene (50 mL) under a Nitrogen atmosphere. The resulting mixture
was heated to 100.degree. C. for 21 hours, then allowed to cool to
r.t., diluted with AcOEt (100 mL) and washed with brine
(3.times.100 mL). The organic extract was dried and concentrated in
vacuo to a residue which was purified by flash chromatography
(CH/AcOEt 9:1) to give ethyl 1,4-dibenzyl-piperazine-2-carboxylate
(5.65 g) as a yellow oil, which was used without any purification
in the next step.
[0218] Diisobutylaluminium hydride (1M in toluene--29 mL) was
dropped into a solution of ethyl
1,4-dibenzyl-piperazine-2-carboxylate (5.47 g) in anhydrous toluene
(110 mL) previously cooled to -78.degree. C. under a Nitrogen
atmosphere. The solution was stirred at -78.degree. C. for 1 hour,
then a 20% sodium hydroxide solution (20 mL) was added and the
mixture was allowed to warm to r.t. Further 20% sodium hydroxide
solution (50 mL) was added and the solution was extracted with Et2O
(2.times.150 mL). The combined organic extracts were dried and
concentrated in vacuo to give the title compound (5.33 g) as a
crude, which was used without any further purification in the next
step.
[0219] T.l.c.: CH/AcOEt 8:2, Rf=0.36.
[0220] NMR (d.sub.6-DMSO): .delta. (ppm) 9.62 (s, 1H); 7.4-7.15 (m,
10H); 3.86 (d, 1H); 3.6 (d, 1H); 3.46 (s, 2H); 3.09 (bt, 1H); 2.82
(t, 1H); 2.55-2.45 (m, 2H); 2.4-2.3 (m, 3H).
Intermediate 12
Hexahydro-pyrrolo[1,2-a]pyrazin-6-one
Method A:
[0221] (Carbethoxymethylene)triphenylphosphorane (11.72 g) was
added in two portions to a solution of intermediate 11 (4.95 g) in
anhydrous toluene (100 mL) under a Nitrogen atmosphere. The mixture
was heated to 80.degree. C. for 24 hours, then it was allowed to
cool to r.t. and washed with water (100 mL). The organic layer was
dried and concentrated in vacuo to a residue, which was purified by
flash chromatography (CH/AcOEt 85:15) to give ethyl
1,4-dibenzyl-2-piperazine-3-acrylate (4.2 g--T.l.c.: CH/AcOEt 8:2,
Rf=0.36).
[0222] A solution of ethyl 1,4-dibenzyl-2-piperazine-3-acrylate
(2.84 g) in abs. EtOH (40 mL) was hydrogenated over Pd/C 10% (1.42
g) at 3.5 atm. for 2 days. After filtration, the solution was
concentrated to nearly 30 mL and heated to 70.degree. C. for 16
hours until complete cyclization occurred. The solution was
concentrated in vacuo and the residue was purified by flash
chromatography (DCM/MeOH 7:3) to give the title compound (820 mg)
as a pale yellow oil.
Method B:
[0223] Diisobutylaluminium hydride (1.2M in toluene--262 mL) was
dropped into a solution of ethyl
1,4-dibenzyl-piperazine-2-carboxylate (48.4 g) synthesised as
previously described in anhydrous toluene (450 mL) previously
cooled to -78.degree. C. under a Nitrogen atmosphere (addition of
DIBAL-H took 1.5 hours and the internal temperature was always
maintained below -70.degree. C.). The solution was stirred at
-78.degree. C. for 2 hour, then a 10% sodium hydroxide solution
(500 mL) was added and the mixture was allowed to warm to r.t.
Further 10% sodium hydroxide solution (400 mL) was added and the
solution was extracted with toluene (2.times.250 mL). The combined
organic extracts were dried and concentrated in vacuo until a
volume of .about.100 mL containing
1,4-dibenzyl-2-piperazinecarboxaldehyde, which was used without any
further purification in the next step.
[0224] (Carbethoxymethylene)triphenylphosphorane (75 g) was added
in two portions to the previous solution of
1,4-dibenzyl-2-piperazine carboxaldehyde in toluene (450 mL) under
a Nitrogen atmosphere. The mixture was heated to 80.degree. C.
overnight, then it was allowed to cool to r.t. and washed with
water (2.times.400 mL) and brine (250 mL) The organic layer was
dried and concentrated in vacuo to a residue, which was purified by
flash chromatography (CH/AcOEt 85:15) to give ethyl
1,4-dibenzyl-2-piperazine-3-acrylate (44.8 g--T.l.c.: CH/AcOEt 8:2,
Rf=0.36).
[0225] To a solution of ethyl 1,4-dibenzyl-2-piperazine-3-acrylate
(44.8 g) in MeOH (450 mL) under a Nitrogen atmosphere, ammonium
formate (23.2 g) and 5% palladium on charcoal (8.96 g) were added.
The resulting mixture was heated to reflux temperature for 6 h.
After filtration over Celite, the solution was concentrated in
vacuo and the residue was purified by flash chromatography
(DCM/MeOH 8:2) to give the title compound (14.15 g) as a pale
yellow oil.
Method C:
[0226] Intermediate 15 (820 g) and toluene (1680 g) were charged in
a 5 L stainless steel autoclave and palladium on charcoal (5%,
dry--50 g) was added. The autoclave was rendered inert with
nitrogen, subsequently filled with 100 bar hydrogen, and then
heated to 100.degree. C. When the internal pressure has fallen to
90 bar, the pressure was increased to 100 bar again. After the
hydrogen uptake ceased, the autoclave was cooled below 30.degree.
C. and the reaction solution was removed. The catalyst was then
filtered off with a buchner funnel and washed with toluene
(2.times.200 mL). After concentrating the filtrate with a rotatory
evaporator, the product was distilled over a 15 cm Vigreux column
(bp: 115 to 125.degree. C. @ 0.07 mbar) giving title compound 12
(574 g) as a slightly yellowish oil.
[0227] T.l.c.: DCM/MeOH 7:3, Rf=0.17 (detection with ninhydrin)
[0228] NMR (CDCl3): .delta. (ppm) 4.01 (m, 1H); 3.54 (m, 1H); 3.16
(m, 1H); 3.01 (m, 1H); 2.81 (m, 1H); 2.6 (dt, 1H); 2.38 (m, 3H);
2.16 (m, 1H); 1.6 (m, 1H).
[0229] MS (ES/+): m/z=141 [M+H].sup.+
Intermediates 13
(8aS)-Hexahydro-pyrrolo[1,2-a]pyrazin-6-one (13a) and
(8aR)-Hexahydro-pyrrolo[1,2-a]pyrazin-6-one (13b)
Method A:
[0230] Intermediate 12 (746 mg) was separated into the enantiomers
via preparative HPLC (Column: Chiralpack AD 25.times.2 cm; mobile
phase: n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm). Thus,
intermediate 13a (330 mg) and intermediate 13b (320 mg) were
obtained.
Intermediate 13a
Enantiomer 1
[0231] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 10.7 minutes.
[0232] Ratio 13a/13b=100:0.
Intermediate 13b
Enantiomer 2
[0233] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 12.8 minutes.
[0234] Ratio 13a/13b=0:100.
Intermediate 13b
Method B:
[0235] A solution of L-(+)-mandelic acid (13.03 g) in isopropanol
(60 mL) was dropped over 20 minutes into a solution of intermediate
12 (12 g) in isopropanol (60 mL) under a Nitrogen atmosphere. The
suspension was stirred at 23.degree. C. for 2 hours, then it was
filtered off and washed with further isopropanol (120 mL). The
solid obtained (ratio enantiomers 20:80) was recrystallized three
times from isopropanol (10 volumes) until a complete HPLC
enantioselectivity was detected. In this way,
(8aR)-hexahydro-pyrrolo[1,2-a]pyrazin-6-one L-(+)-mandelate (5.84
g--enantiomer 2) was obtained.
[0236] This material (6.469 g) was dissolved in EtOH (40 mL) and
water (4 mL) and stirred with a suspension of resin IRA68 (112
g--previously washed with a 0.05N sodium hydroxide solution (370
mL) and water (4 L) until neutral pH) in EtOH (200 mL). The mixture
was stirred at 23.degree. C. for 1.5 hours, then filtered off. The
organic layer was concentrated in vacuo to give the title compound
13b (3.1 g) as a white solid.
Intermediate 13b
[0237] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 12.8 minutes.
[0238] Ratio 13a/13b=0:100.
Intermediate 13a
Method B:
[0239] A part of the mother liquors (3.48 g with ratio
13a:13b=63:37) was treated with a suspension of resin IRA68 (70
g--previously washed with a 0.05N sodium hydroxide solution (150
mL) and water until neutral pH) in EtOH (150 mL) and water (1 mL).
The mixture was stirred at 23.degree. C. for 2 hours, then filtered
off. The organic layer was concentrated in vacuo to give the free
hexahydro-pyrrolo[1,2-a]pyrazin-6-one (1.6 g) as colourless oil.
This material (1.6 g) was dissolved in isopropanol (8 mL) and
treated with a solution of D-(-)-mandelic acid (1.74 g) in
isopropanol (8 mL).
[0240] The suspension was stirred at 23.degree. C. for 16 hours,
then it was filtered off and washed with further isopropanol (120
mL). The solid obtained (ratio enantiomers 86:14) was
recrystallized three times from isopropanol (10 volumes) until a
complete HPLC enantioselectivity was detected. In this way,
(8aS)-hexahydro-pyrrolo[1,2-a]pyrazin-6-one D-(-)-mandelate (0.88
g--enantiomer 1) was obtained.
[0241] This material (0.88 g) was dissolved in EtOH (10 mL) and
water (1 mL) and stirred with a suspension of resin IRA68 (15
g--previously washed with a 0.05N sodium hydroxide solution (50 mL)
and water until neutral pH in EtOH (30 mL). The mixture was stirred
at 23.degree. C. for 1 hour, then filtered off. The organic layer
was concentrated in vacuo to give the title compound 13a (0.434 g)
as a white solid.
Intermediate 13a
[0242] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 10.7 minutes. Ratio 13a/13b=100:0.
Intermediate 14
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide
[0243] A saturated sodium hydrogen carbonate solution (15 mL) was
added to a solution of intermediate 9 (1.0 g) in AcOEt (15 mL) and
the resulting mixture was vigorously stirred for 15 minutes. The
aqueous layer was back-extracted with further AcOEt (10 mL) and the
collected organic phases were dried and concentrated in vacuo to
give the free base
2-(R)-(4-fluoro-2-methyl-phenyl)-4-oxo-piperidine (0.550 g) as a
yellow oil.
[0244] A solution of
2-(R)-(4-fluoro-2-methyl-phenyl)-4-oxo-piperidine (0.550 g) and TEA
(20.5 mL) in AcOEt (5.5 mL) was added drop-wise, over 40 minutes,
to a solution of triphosgene (0.385 g) in AcOEt (2.75 mL)
previously cooled to 0.degree. C. under a nitrogen atmosphere. The
solution was allowed to warm to r.t. and stirred at 23.degree. C.
for 2 hours, then N-(3,5-dichloro)-benzyl-methylamine hydrochloride
(3.17 g) and TEA (1.860 mL) in AcOEt (8.25 mL) were added. The
reaction mixture was stirred for 2 hours at 20.degree. C., then it
was washed with 10% sodium hydroxide solution (3.times.8 mL) and 1%
hydrochloric acid solution (3.times.8 mL). The organic layer was
dried and concentrated in vacuo to a residue which was purified
through a silica pad (CH/AcOEt from 9/1 to 1/1) to give the title
compound (0.870 g) as a colourless oil.
[0245] T.l.c.: CH/AcOEt 1:1, Rf=0.40.
[0246] NMR (d.sub.6-DMSO): .delta. (ppm) 7.45 (t, 1H); 7.29 (m,
1H); 7.07 (d, 2H); 7.0-6.94 (m, 2H); 5.16 (dd, 1H); 4.40-4.26 (dd,
2H); 3.55 (m, 2H); 2.76 (s, 3H); 2.75-2.6 (m, 2H); 2.5 (m, 2H);
2.29 (s, 3H).
Intermediate 15
3-Pyrazin-2-yl-propionic acid ethyl ester
[0247] Butyl lithium (2.5M in hexane--2560 mL) was added within 2
hours into a 10 L flask charged with THF (3350 mL) and
diisopropylamine (658 g) while the temperature was maintained at
0-5.degree. C. with an ice bath. The LDA solution was then
precooled to -50.degree. C. and a mixture of methylpyrazine (606 g)
and THF (590 mL) was added within 2 hours under vigorous stirring
at -40 to -30.degree. C. The deep red anion solution is then pumped
to a cooled (-60.degree. C.) mixture of tert-butyl bromoacetate
(1255 g) and THF (3360 mL) in a 20 L reactor. During the addition
of the anion solution, the temperature in the reaction vessel did
not exceed -55.degree. C. After the addition, the mixture is
stirred for further 30 min at -55.degree. C. and then transferred
to a 30 L reactor (the transesterification and removal of solvents
can be done for two runs at once). A solution of sodium ethylate
(142 g) dissolved in EtOH (2200 mL) was then added to the orange
mixture and about 12 L of solvents were distilled off until a
temperature of 80.degree. C. was reached in the distillation head
and 100.degree. C. in the boiling liquid. The mixture was cooled to
approximately 30.degree. C. and then toluene (840 mL), AcOEt (840
mL), and water (1180 mL) were added. After separation of the
phases, the organic layer was extracted three times with AcOEt (420
mL) and toluene (170 mL) each. The combined organic phases were
then concentrated in vacuo and the residue was distilled over a
Vigreux column (bp 115 to 130.degree. C. @ 0.07 mbar) giving the
title compound (579 g).
[0248] T.l.c.: CH/EtOAc=1:1, Rf=0.36.
[0249] .sup.1H-NMR (d.sub.6-DMSO): .delta. (ppm) 8.57 (d, 1H); 8.52
(dd, 1H); 8.45 (d, 1H); 4.01 (q, 2H); 3.04 (t, 2H); 2.76 (t, 2H);
1.12 (t, 3H).
[0250] MS (ES/+): m/z=181 [M+H].sup.+
Intermediate 16
(8aS)-Hexahydro-pyrrolo[1,2-a]pyrazin-6-one S-(+)-O-acetylmandelate
(enantiomer 1)
[0251] A solution of (S)-(+)-O-acetylmandelic acid (2.77 g) in
acetone (12 mL) was added drop-wise to a solution of intermediate
12 (4 g) in acetone (28 mL) at 20.degree. C. The resulting mixture
was seeded to initiate the precipitation.
[0252] The obtained precipitate was stirred at 20.degree. C. over 4
hours then filtered washing with acetone (12 mL). The solid was
dried in vacuo at 40.degree. C. for 18 hours to give the title
compound (3.44 g) as a white solid.
[0253] HPLC: Column Chiralpack AD 25.times.4.6.times.5 .mu.m;
mobile phase n-hexane/EtOH=1:1; flow=1 ml/min; .lamda.=210 nm;
retention times title compound 5.42 min., (8aR) enantiomer 6.06
min. E.e.>94%.
[0254] .sup.1H-NMR (d.sub.6-DMSO): .delta. (ppm) 9.5 (broad, 1H);
7.42 (m, 2H); 7.32 (m, 3H); 5.62 (s, 1H); 3.79 (dd, 1H); 3.55 (m,
1H); 3.14-3.02 (2dd, 2H); 2.80 (dt, 1H); 2.52 (dt, 1H); 2.40 (t,
1H); 2.19 (m, 2H); 2.06 (s, 3H); 2.05 (m, 1H); 1.49 (m, 1H).
[0255] MS (ES/+): m/z=141 [M+H-PhCH(OAc)COOH].sup.+.
Intermediate 17
(4-Fluoro-2-methyl-phenylimino)-acetic acid ethyl ester
[0256] A solution of ethyl glyoxalate (50% solution in
toluene--40.8 mL) in toluene (180 mL) was heated to reflux for 1.5
hours under a Nitrogen atmosphere, in a flask equipped with a Dean
Stark apparatus. Then, a solution of 4-fluoro-2-methyl-aniline (10
g) in dry toluene (20 mL) was slowly added. The mixture was heated
to reflux for 3 hours, then it was concentrated in vacuo. The
residue was purified by flash chromatography (toluene/CH/AcOEt
4:4:2) to give the title compound (13.06 g) as a yellow oil.
[0257] T.l.c.: toluene/CH/AcOEt 4:4:2, Rf=0.67.
[0258] NMR (CDCl3): .delta. (ppm) 7.8 (s, 1H); 6.95 (d, 1H); 6.85
(d, 2H); 4.4 (q, 2H); 2.35 (s, 3H); 3.3 (t 3H).
[0259] MS (ES/+): m/z=210 [M+H].sup.+.
Intermediate 18
1-(4-Fluoro-2-methyl-phenyl)-4-oxo-1,2,3,4-tetrahydro-pyridine-2-carboxyli-
c acid ethyl ester
[0260] Boron trifluoride etherate (1.22 mL) was added to a solution
of intermediate 17 (2 g) in anhydrous DCM (20 mL) previously cooled
to -78.degree. C. under a Nitrogen atmosphere. After stirring for
15 minutes at -78.degree. C., the
1-methoxy-3-trimethylsiloxy-1,3-butadiene (2.67 mL) was dropped
over 45 minutes. The resulting solution was stirred at -78.degree.
C. for 2 hours, then TFA (0.74 mL) was added. The mixture was
stirred at 0.degree. C. for 15 minutes, then a saturated sodium
hydrogen carbonate solution was added and the mixture was extracted
with AcOEt (3.times.50 mL). The combined organic extracts were
dried and concentrated in vacuo to give a residue, which was
purified by flash chromatography (CH/AcOEt from 8:3 to 7:3) to give
the title compound (1.5 g) as a pale yellow solid.
[0261] T.l.c.: CH/AcOEt 6:4, Rf=0.2.
[0262] NMR (CDCl3): .delta. (ppm) 7.4 (dd, 1H); 7.1 (d, 1H);
7.0-6.8 (m, 2H); 5.15 (d, 1H); 4.4 (m, 1H); 4.1 (m, 2H); 3.1-2.85
(m, 2H); 2.4 (s, 3H); 1.15 (t, 3H).
Intermediate 19
1-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-2-carboxylic acid
ethyl ester
[0263] L-selectride (1M solution in dry THF, 3.96 mL) was added
drop-wise, over 1 hour, to a solution of intermediate 18 (1 g) in
dry THF (30 mL) previously cooled to -78.degree. C. under a
Nitrogen atmosphere. After 1 hour, a saturated sodium hydrogen
carbonate solution (20 mL) was added drop-wise and the solution was
extracted with AcOEt (3.times.50 mL). The combined organic extracts
were dried and concentrated in vacuo to a residue, which was
purified by flash chromatography (CH/AcOEt 8:2) to give the title
compound (810 mg) as a white solid.
[0264] T.l.c.: CH/AcOEt 6:4, Rf=0.6.
[0265] NMR (CDCl3): .delta. (ppm) 7.4 (dd, 1H); 7.1 (dd, 1H); 6.9
(dd, 1H); 6.8 (dt, 1H); 4.2 (q, 2H); 4.15 (m, 1H); 3.6 (m, 1H); 3.2
(m, 1H); 2.8-2.7 (dd, 2H); 2.6 (m, 2H); 2.4 (s, 3H); 1.2 (t,
3H).
Intermediate 20
1-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-2-carboxylic acid
[0266] Lithium hydroxide monohydrate (241 mg) was added to a
solution of intermediate 19 (300 mg) in MeOH (15 mL) and water (3
mL) and the resulting solution was stirred at 80.degree. C. for 1
hour. The solution was allowed to cool to r.t. and extracted with
Et2O. The aqueous layer was acidified until pH=6 with acetic acid
and extracted with AcOEt (3.times.15 mL). The combined organic
extractes were dried and concentrated in vacuo to give the title
compound (230 mg) as yellow solid, which was used without any
further purification in the next step.
[0267] MS (ES/+): m/z=252 [M+H].sup.+.
Intermediate 21
1-(4-Fluoro-2-methyl-phenyl)-4-oxo-piperidine-2-carboxylic acid,
(3,5-bis-trifluoromethyl-benzyl)-methylamide
[0268] DIPEA (2.6 mL) and
O-(benzotriazol-1-yl)-N,N,N'N'-tetramethyluronium
hexafluorophosphate (2.48 g) were added to a solution of
intermediate 20 (1.259 g) in anhydrous DMF (25 mL) under a Nitrogen
atmosphere. After stirring 30 minutes,
(3,5-bis-trifluoromethyl-benzyl)-methylamine hydrochloride (1.62 g)
was added and the mixture was stirred at r.t. for 16 hours. The
reaction mixture was diluted with AcOEt (50 mL) and washed with a
saturated ammonium chloride solution (30 mL), a saturated sodium
hydrogen carbonate solution (30 mL) and brine (3.times.50 mL). The
organic extracts were dried and concentrated in vacuo. The residue
was purified by flash chromatography (CH/AcOEt 9:1) to give the
title compound (1.59 g) as a dark yellow oil.
[0269] T.l.c.: CH/AcOEt 1:1, Rf=0.25.
[0270] NMR (d.sub.6-DMSO): .delta. (ppm) 8.03 (bs, 1H); 7.84 (bs,
2H); 7.03 (dd, 1H); 6.79 (dd, 1H); 6.64 (td, 1H); 4.80 (d, 1H);
4.67 (m, 1H); 4.29 (d, 1H); 3.55 (m, 1H); 3.04 (m, 1H); 2.74 (m,
1H); 2.5 (m, 1H); 2.4-2.2 (m, 2H); 2.40 (s, 3H); 2.38 (s, 3H).
[0271] MS (ES/+): m/z=491 [M+H].sup.+.
Example 1
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-(6-oxo-hexahydro-pyrrolo[1,2-a]-pyr-
azin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (1a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-py-
razin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (1b)
[0272] A solution of intermediate 12 (129 mg) in anhydrous
acetonitrile (2 mL) was added to a solution of intermediate 10 (300
mg) in anhydrous acetonitrile (5 mL) under a Nitrogen atmosphere.
The solution was stirred at r.t. for 15 minutes, then sodium
triacetoxyborohydride (233 mg) was added. The mixture was stirred
at 23.degree. C. for 2 days. The solution was diluted with AcOEt
(15 mL) and washed with a 5% sodium hydrogen carbonate solution (15
mL) and brine (10 mL). The organic layer was dried and concentrated
in vacuo to a residue which was purified by flash chromatography
(AcOEt/MeOH 8:2) to give two fractions:
[0273] 1. example 1a (21.9 mg)
[0274] 2. example 1b (48 mg).
Example 1a
[0275] T.l.c.: AcOEt/MeOH 8:2, Rf=0.38.
[0276] NMR (d.sub.6-DMSO): .delta. (ppm) 7.95 (bs, 1H); 7.71 (bs,
2H); 7.31 (dd, 1H); 6.94 (dd, 1H); 6.85 (dt, 1H); 4.89 (m, 1H);
4.55 (d, 1H); 4.41 (d, 1H); 3.78 (m, 1H); 3.52 (m, 1H); 3.35 (m,
1H); 3.14-3.05 (2m, 1H); 3.12 (m, 1H); 2.96-2.91 (2m, 1H); 2.81 (s,
3H); 2.74 (m, 1H); 2.62 (m, 1H); 2.26 (2s, 3H); 2.24 (m, 1H); 2.16
(m, 1H); 2.07 (m, 1H); 1.9 (m, 2H); 1.82 (m, 1H); 1.75 (m 1H); 1.72
(m, 2H); 1.51 (m, 1H).
[0277] MS (ES/+) m/z=615 [M+H].sup.+.
Example 1b
[0278] T.l.c.: AcOEt/MeOH 8:2, Rf=0.28.
[0279] NMR (d.sub.6-DMSO): .delta. (ppm) 7.94 (s, 1H); 7.59 (s,
2H); 7.23 (dd, 1H); 6.89 (dd, 1H); 6.77 (dt, 1H); 4.62 (d, 1H);
4.36 (d, 1H); 4.14 (d, 1H); 3.73 (dd, 1H); 3.45 (m, 2H); 2.97 (dd,
1H); 2.9 (s, 3H); 2.81 (bt, 1H); 2.66 (m, 3H); 2.34 (s, 3H); 2.17
(m, 2H); 2.03 (m, 2H); 1.84 (m, 2H); 1.75 (bt, 1H); 1.65 (m, 1H);
1.5 (m, 1H); 1.39 (m, 1H).
[0280] MS (FAB/NBA) m/z=615 [M+H].sup.+.
Example 2
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-(6-oxo-hexahydro-pyrrolo[1,2-a]-pyr-
azin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride
[0281] A solution of example 1b (46 mg) in dry Et2O (2 mL) was
treated with hydrochloric acid (1M in Et2O--0.083 mL) at 0.degree.
C. under a Nitrogen atmosphere. The resulting solution was stirred
at 0.degree. C. for 30 minutes, then it was concentrated in vacuo
and the residue was triturated with pentane (2.times.3 mL) to give
the title compound as a white solid (39.4 mg).
[0282] NMR (d.sub.6-DMSO): .delta. (ppm) 10.34 (bs, 1H); 7.96 (bs,
1H); 7.6 (bs, 2H); 7.28 (m, 1H); 6.85 (m, 1H); 6.83 (m, 1H); 4.63
(d, 1H); 4.37 (bd, 1H); 4.22 (bd, 1H); 4.0 (bd, 1H); 3.88 (m, 1H);
3.7-3.2 (m, 6H); 2.94 (s, 3H); 2.4-2.0 (m, 4H); 2.35 (t, 3H); 2.34
(s, 3H); 1.95 (m, 2H); 1.8-1.5 (m, 2H).
[0283] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
Examples 3
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (3a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (3b)
[0284] Intermediate 13a (259.3 mg) was added to a solution of
intermediate 10 (550 mg) in anhydrous acetonitrile (10 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 30
minutes, then sodium triacetoxyborohydride (474.8 mg) was added.
The mixture was stirred at 23.degree. C. for 8 hours. The solution
was diluted with a 5% sodium hydrogen carbonate solution (15 mL)
and extracted with AcOEt (3.times.25 mL). The combined organic
extracts were dried and concentrated in vacuo to a residue which
was purified by flash chromatography (AcOEt/MeOH 8:2) to give two
fractions:
[0285] 1. example 3a (177 mg)
[0286] 2. example 3b (280 mg).
Example 3a
[0287] T.l.c.: AcOEt/MeOH 8:2, Rf=0.38.
[0288] NMR (d.sub.6-DMSO): .delta. (ppm) 7.96 (s, 1H); 7.72 (s,
2H); 7.31 (dd, 1H); 6.95 (dd, 1H); 6.86 (dt, 1H); 4.89 (t, 1H);
4.55 (d, 1H); 4.42 (d, 1H); 3.8 (d, 1H); 3.52 (m, 1H); 3.35 (m,
1H); 3.13 (m, 1H); 3.06 (m, 1H); 2.96 (m, 1H); 2.81 (s, 1H); 2.75
(m, 1H); 2.64 (m, 1H); 2.26 (s, 3H); 2.23-2.17 (m, 2H); 2.07 (m,
1H); 1.9 (m, 2H); 1.81-1.71 (m, 4H); 1.52 (m, 1H).
[0289] MS (ES/+) m/z=615 [M+H].sup.+.
Example 3b
[0290] T.l.c.: AcOEt/MeOH 8:2, Rf=0.28.
[0291] NMR (d.sub.6-DMSO): .delta. (ppm) 7.94 (s, 1H); 7.59 (s,
2H); 7.23 (dd, 1H); 6.89 (dd, 1H); 6.77 (dt, 1H); 4.62 (d, 1H);
4.36 (d, 1H); 4.14 (d, 1H); 3.73 (dd, 1H); 3.45 (m, 2H); 2.97 (dd,
1H); 2.9 (s, 3H); 2.81 (bt, 1H); 2.66 (m, 3H); 2.34 (s, 3H); 2.17
(m, 2H); 2.03 (m, 2H); 1.84 (m, 2H); 1.75 (bt, 1H); 1.65 (m, 1H);
1.5 (m, 1H); 1.39 (m, 1H).
[0292] MS (ES/+) m/z=615 [M+H].sup.+.
Example 4
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride
[0293] A solution of example 3a (50 mg) in dry Et2O (2 mL) was
treated with hydrochloric acid (1M in Et2O--0.09 mL) at 0.degree.
C. under a Nitrogen atmosphere. The resulting solution was stirred
at 0.degree. C. for 10 minutes, then it was concentrated in vacuo
and the residue was triturated with pentane (2.times.2 mL) to give
the title compound as a white solid (50.8 mg).
[0294] NMR (d.sub.6-DMSO): .delta. (ppm) 10.96 (bs, 1H); 7.99 (bs,
1H); 7.81 (bs, 2H); 7.39 (m, 1H); 7.01 (dd, 1H); 6.93 (m, 1H); 5.26
(t, 1H); 4.57 (d, 1H); 4.41 (d, 1H); 4.1-3.75 (bm, 2H); 3.7-3.5 (m,
4H); 3.2 (m, 1H); 3.16 (m, 1H); 2.95 (s, 1H); 2.86 (m, 1H); 2.73
(s, 3H); 2.23 (s, 3H); 2.5-2.1 (m, 5H); 1.71 (m, 1H); 1.6 (m, 1H);
1.25 (m, 1H).
[0295] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
Example 5
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride
[0296] A solution of example 3b (275 mg) in dry Et2O (5 mL) was
treated with hydrochloric acid (1M in Et2O--0.5 mL) at 0.degree. C.
under a Nitrogen atmosphere. The resulting solution was stirred at
0.degree. C. for 30 minutes, then it was concentrated in vacuo and
the residue was triturated with pentane (2.times.3 mL) to give the
title compound as a white solid (268 mg).
[0297] NMR (d.sub.6-DMSO): .delta. (ppm) 11.1 (bs, 1H); 7.95 (bs,
1H); 7.6 (bs, 2H); 7.26 (dd, 1H); 6.94 (dd, 1H); 6.82 (m, 1H); 4.63
(d, 1H); 4.37 (d, 1H); 4.21 (dd, 1H); 3.97 (m, 2H); 3.55 (m, 4H);
3.21 (m, 1H); 2.93 (s, 3H); 2.85 (m, 2H); 2.75 (m, 1H); 2.32 (s,
3H); 2.4-2.1 (m, 5H); 1.97 (m, 1H); 1.69 (q, 1H); 1.57 (m, 1H).
[0298] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
[0299] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 8.7 minutes.
Examples 6
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (6a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide (6b)
[0300] A solution of intermediate 13b (3.1 g) in anhydrous
acetonitrile (60+50 mL) was added to a solution of intermediate 10
(7.2 g) in anhydrous acetonitrile (40 mL) under a Nitrogen
atmosphere. The solution was stirred at r.t. for 20 minutes, then
sodium triacetoxyborohydride (5.6 g) was added. The mixture was
stirred at 23.degree. C. for 13 hours. The solution was diluted
with a 5% sodium hydrogen carbonate solution (30 mL) and water (90
mL), stirred at 23.degree. C. for 10 minutes, then concentrated in
vacuo to eliminate the acetonitrile. The residue was extracted with
AcOEt (2.times.200 mL). The combined organic extracts were washed
with brine (300 mL), dried and concentrated in vacuo to a residue
which was purified by flash chromatography (AcOEt/MeOH 8:2) to give
two fractions:
[0301] 1. example 6a (2.0 g)
[0302] 2. example 6b (3.67 g).
Example 6a
[0303] T.l.c.: AcOEt/MeOH 8:2, Rf=0.49.
[0304] NMR (d.sub.6-DMSO): .delta. (ppm) 7.96 (bs, 1H); 7.72 (bs,
2H); 7.31 (bt, 1H); 6.95 (dd, 1H); 6.86 (dt, 1H); 4.89 (m, 1H);
4.55 (d, 1H); 4.42 (d, 1H); 3.78 (m, 1H); 3.53 (m, 1H); 3.35 (m,
1H); 3.14 (m, 2H); 2.92 (m, 1H); 2.82 (s, 3H); 2.75 (m, 1H); 2.63
(m, 1H); 2.27 (s, 3H); 2.23-2.17 (m, 2H); 2.08 (m, 1H); 1.91-1.7
(m, 6H); 1.52 (m, 1H).
[0305] MS (ES/+) m/z=615 [M+H].sup.+.
Example 6b
[0306] T.l.c.: AcOEt/MeOH 8:2, Rf=0.33.
[0307] NMR (d.sub.6-DMSO): .delta. (ppm) 7.94 (s, 1H); 7.59 (s,
2H); 7.23 (dd, 1H); 6.89 (dd, 1H); 6.77 (dt, 1H); 4.62 (d, 1H);
4.36 (d, 1H); 4.14 (d, 1H); 3.73 (dd, 1H); 3.45 (m, 2H); 2.97 (dd,
1H); 2.9 (s, 3H); 2.81 (bt, 1H); 2.66 (m, 3H); 2.34 (s, 3H); 2.17
(m, 2H); 2.03 (m, 2H); 1.84 (m, 2H); 1.75 (bt, 1H); 1.65 (m, 1H);
1.5 (m, 1H); 1.39 (m, 1H).
[0308] MS (ES/+) m/z=615 [M+H].sup.+.
Example 7
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride
[0309] A solution of example 6a (50 mg) in dry Et2O (2 mL) was
treated with hydrochloric acid (1M in Et2O--0.09 mL) at 0.degree.
C. under a Nitrogen atmosphere. The resulting solution was stirred
at 0.degree. C. for 10 minutes, then it was concentrated in vacuo
and the residue was triturated with pentane (2.times.2 mL) to give
the title compound as a white solid (50.67 mg).
[0310] NMR (d.sub.6-DMSO): .delta. (ppm) 10.96 (bs, 1H); 7.98 (bs,
1H); 7.81 (bs, 2H); 7.38 (m, 1H); 7.01 (dd, 1H); 6.93 (m, 1H); 5.26
(bt, 1H); 4.56 (d, 1H); 4.41 (d, 1H); 4.1-3.8 (bm, 2H); 3.67 (m,
2H); 3.49 (bd, 2H); 3.21 (m, 2H); 3.13 (m, 1H); 2.91 (m, 1H); 2.73
(s, 3H); 2.24 (s, 3H); 2.5-2.1 (m, 5H); 1.73 (m, 1H); 1.59 (m, 1H);
1.25 (m, 1H).
[0311] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
Example 8
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methylamide hydrochloride
[0312] A solution of example 6b (3.0 g) in dry Et2O (30 mL) was
treated with hydrochloric acid (1M in Et2O--5.37 mL) at 0.degree.
C. under a Nitrogen atmosphere. The resulting mixture was stirred
at 0.degree. C. for 1.5 hours, then pentane (5 mL) and the solid
was filtered off. The precipitate was washed with pentane (20 mL),
Et2O (5 mL) and further pentane (15+30 mL) to give the title
compound as a white solid (3.1 g).
[0313] NMR (d.sub.6-DMSO): .delta. (ppm) 11.06 (bs, 1H); 7.95 (bs,
1H); 7.6 (bs, 2H); 7.27 (dd, 1H); 6.94 (dd, 1H); 6.82 (m, 1H); 4.63
(d, 1H); 4.37 (d, 1H); 4.22 (dd, 1H); 3.97 (m, 2H); 3.56 (m, 4H);
3.21 (m, 1H); 2.93 (s, 3H); 2.89 (m, 2H); 2.75 (m, 1H); 2.36 (s,
3H); 2.4-2.1 (m, 5H); 1.91 (m, 1H); 1.72 (q, 1H); 1.57 (m, 1H).
[0314] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
[0315] HPLC: Column Chiralpack AD 25 cm.times.4.6 mm.times.5;
mobile phase n-hexane/EtOH 8:2; flux=1 mL/min; .lamda.=225 nm;
retention time 9.5 minutes.
Example 9
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (9a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (9b)
Method A:
[0316] Intermediate 4a (168 mg) and sodium triacetoxyborohydride
(127 mg) were added to a solution of intermediate 13a (80 mg) in
anhydrous acetonitrile (4 mL) under a Nitrogen atmosphere. The
mixture was stirred at 23.degree. C. for 14 hours. The solution was
diluted with a 5% sodium hydrogen carbonate solution (5 mL) and
extracted with AcOEt (2.times.10 mL). The combined organic extracts
were dried and concentrated in vacuo to a residue which was
purified by flash chromatography (AcOEt/MeOH 9:1) to give three
fractions:
[0317] 1. example 9a (18 mg) a a white solid
[0318] 2. mixture of example 9a and 9b (160 mg)
[0319] 3. example 9b (8 mg) as a white solid.
Method B:
[0320] A solution of intermediate 13a (2.4 g) in anhydrous
acetonitrile (80 mL) was added to a solution of intermediate 4a
(5.7 g) in anhydrous acetonitrile (30 mL) under a Nitrogen
atmosphere. Sodium triacetoxyborohydride (4.36 g) was added in
three portions every 15 minutes and the mixture was stirred at
23.degree. C. for 22 hours. The solution was diluted with water (75
mL) and a saturated sodium hydrogen carbonate solution (25 mL) and
extracted with AcOEt (2.times.200 mL). The combined organic
extracts were dried and concentrated in vacuo to a residue which
was purified by flash chromatography (CH/AcOEt/MeOH 50:50:8) to
give four fractions:
[0321] 1. mixture example 9a and example 9b (1.27 g) in ratio
1:1
[0322] 2. example 9b (1.66 g) (ratio 9a:9b=13:87)
[0323] 3. example 9b (420 mg) (ratio 9a:9b=5:95)
[0324] 4. example 9b (800 mg) (ratio 9a:9b=2:98)
Example 9a
[0325] T.l.c.: AcOEt/MeOH 8:2, Rf=0.55.
[0326] MS (ES/+) m/z=629 [M+H].sup.+.
[0327] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6 mm.times.5;
mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from 60:40 to 10:90 in
5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN for 10 min.; flux=0.8
mL/min; .lamda.=220 nm; retention time 9.27 minutes.
Example 9b
[0328] T.l.c.: AcOEt/MeOH 8:2, Rf=0.48.
[0329] MS (ES/+) m/z=629 [M+H].sup.+.
[0330] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6 mm.times.5;
mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from 60:40 to 10:90 in
5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN for 10 min.; flux=0.8
mL/min; .lamda.=220 nm; retention time 8.84 minutes.
Example 10
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride
[0331] A solution of example 9a (18 mg) in dry Et2O (1.3 mL) was
treated with hydrochloric acid (1M in Et2O--32 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 30 minutes, then the mixture was concentrated in
vacuo. The precipitate was washed with pentane (2 mL) to give the
title compound as a white solid (17.6 mg).
[0332] NMR (d.sub.6-DMSO): .delta. (ppm) 10.65 (bm, 1H); 7.99 (s,
1H); 7.76 (s, 2H); 7.37 (dd, 1H); 7.01 (dd, 1H); 6.93 (dd, 1H);
5.24 (bm, 1H); 5.04 (q, 1H); 4.0-3.95 (bm, 2H); 3.68 (m, 1H); 3.58
(m, 2H); 3.51 (m, 1H); 3.24-3.15 (m, 2H); 2.96 (m, 1H); 2.85 (m,
1H); 2.54 (s, 3H); 2.36-2.13 (m, 6H); 2.21 (s, 3H); 1.72 (m, 1H);
1.59 (m, 1H); 1.57 (d, 3H).
[0333] MS (ES/+) m/z=629 [M+H-HCl].sup.+.
[0334] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6 mm.times.5;
mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from 60:40 to 10:90 in
5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN 10:90 for 10 min.;
flux=0.8 mL/min; .lamda.=220 nm; retention time 9.26 minutes.
Example 11
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride
[0335] A solution of example 9b (8 mg) in dry Et2O (1 mL) was
treated with hydrochloric acid (1M in Et2O--14 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 20 minutes, then the mixture was concentrated in
vacuo. The precipitate was washed with pentane (2 mL) to give the
title compound as a white solid (7.6 mg).
[0336] NMR (d.sub.6-DMSO): .delta. (ppm) 10.22 (bs, 1H); 7.99 (s,
1H); 7.67 (s, 2H); 7.22 (dd, 1H); 6.94 (dd, 1H); 6.81 (t, 1H); 5.31
(q, 1H); 4.2 (dd, 1H); 4.0-3.86 (bm, 2H); 3.6-3.4 (m, 2H); 3.1-2.7
(m, 4H); 2.73 (s, 3H); 2.4-2.0 (m, 5H); 2.35 (s, 3H); 1.94 (m, 1H);
1.74 (q, 1H); 1.57 (d, 3H); 1.46 (d, 3H).
[0337] MS (ES/+) m/z=629 [M+H-HCl].sup.+.
[0338] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6
mm.times.5.mu., mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from
60:40 to 10:90 in 5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN from
10:90 for 10 min.; flux=0.8 mL/min; .lamda.=220 nm; retention time
8.86 minutes.
[0339] Column X-Terra 4.6.times.100 mm, RP18 3.5 .mu.m; mobile
phase: eluant A: NH.sub.4HCO.sub.3 5 mM (pH=8)/CH.sub.3CN
90/10--eluant B: NH.sub.4HCO.sub.3 5 mM (pH=8)/CH.sub.3CN
10/90--Gradient: from 50% B to 100% B in 7.5 min; 100% B for 0.5
min then 50% B for 3 min.; column temp.: 40.degree. C.; flow=1
mL/min; .lamda.=210 nm; retention time 4.15 minutes.
Example 11a
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride as anhydrous crystalline form
[0340] A 2% sodium hydroxide solution (100 mL) was added to a
suspension of example 11c (10 g) in AcOEt (150 mL). Then the two
phases mixture were stirred for 10 minutes and the layers were
separated. The organic phase was washed with water (100 mL) and
then concentrated in vacuo up to 40 mL. AcOEt (100 mL) was added to
the organic phase, which was then concentrated in vacuo a second
time up to 40 mL. The solution was further diluted with AcOEt (60
mL) and 5-6N hydrochloric acid in isopropanol (3 mL) was added.
After 5 minutes the clear solution was seeded. Precipitation
occurred in a few minutes and after further 20 minutes stirring,
n-heptane (100 mL) was added in 10-15 minutes. The obtained mixture
was stirred 2 hours at 20.degree. C. The solid was then filtered,
washed with AOEt/n-heptane 1/1 (60 mL) and dried in vacuo at
40.degree. C. for 16 hours to give the title compound (8.08 g) as a
white solid.
[0341] X ray powder diffraction data are reported in table 1
TABLE-US-00001 TABLE 1 The X-ray podwer diffraction pattern of the
product of the Example 11a in terms of d spacing is as follows
Angle(.degree. 2 Theta) d value(A) 3.412 25.87492 6.87 12.85613
9.867 8.95664 12.877 6.86899 14.274 6.19974 15.4 5.74895 16.732
5.29424 17.323 5.11486 17.966 4.93311 18.521 4.78656 19.557 4.53525
22.12 4.01529 22.382 3.96884 24.311 3.65818 27.117 3.28566 27.836
3.20239 28.374 3.14292 28.846 3.0925 29.372 3.03835 33.9
2.64214
Example 11b
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride as dihydrate crystalline form
[0342] To a 265 mg of example 11a, 3 ml of water was added. The
suspension was stirred overnight at 25.degree. C. and then
centrifuged for 5 min at 10000 rpm. The solid was filtered using a
centrifugal filter device (Millipore Ultrafree-MC 0.45 .mu.m) to
obtain the title compound (250 mg)
[0343] X ray powder diffraction data are reported in table 2
TABLE-US-00002 TABLE 2 The X-ray podwer diffraction pattern of the
product of the Example 11b in terms of d spacing is as follows
Angle(.degree. 2-Theta) d value(A) 3.233 27.30972 6.353 13.90157
12.14 7.28437 12.647 6.99378 13.282 6.6605 13.5 6.55347 15.48
5.71928 16.324 5.42557 16.779 5.27951 17.825 4.97188 19.022 4.66158
19.414 4.5685 19.901 4.45772 21.339 4.1605 21.915 4.05245 22.21
3.99923 23.161 3.83714 23.521 3.77915 24.179 3.67782 25.417 3.50136
26 3.42415 26.668 3.33994 28.052 3.17821 28.553 3.1236 29.551
3.0203 31.297 2.85568 32.8 2.72816 34.148 2.62353
Example 11c
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
maleate
Method A:
[0344] Intermediate 16 (25 g) was suspended in acetonitrile (300
mL), then TEA (10.4 mL) was quickly added in order to obtain the
free base: the aspect of the slurry did not change as a new
precipitate of TEA-acetylmandelate salt was formed. The mixture was
kept under stirring for 15-20 minutes. Meanwhile intermediate 4a
(25 g) was dissolved in acetonitrile (125 mL) and the so-obtained
solution was quickly added to the slurry. Then Sodium
triacetoxyborohydride (15 g) was added all at once and the mixture
was kept under stirring conditions for 22 hours. The white
precipitate was filtered off and the mother liquors were evaporated
to 100 mL. AcOEt (250 mL) was added to the so-obtained mixture and
the resulting solution was washed with aqueous 4% sodium hydrogen
carbonate solution (2.times.125 mL) and then with 5% sodium
chloride solution (125 mL). The organic layer dried and evaporated
to 100 mL. Isopropyl alcohol (150 ml) was added and the mixture was
evaporated again to 100 mL. This operation was repeated. The final
volume of the mixture was adjusted to 200 mL adding further
isopropyl alcohol (100 mL). A solution of maleic acid (5.8 g) in
isopropyl alcohol (50 mL) was dropped in ca. 10 minutes. The
mixture was seeded and precipitation occurred in few minutes. The
slurry was stirred 1 hour at 20.degree. C. and isoctane (250 mL)
was added in 10 minutes. The resulting suspension was stirred at
room temperature for 22 hours. The solid was filtered and washed
with isopropanol/isoctane 1/1 (150 mL) and dried in vacuo at
40.degree. C. for 18 hours giving the title compound (13.75 g) as a
white solid.
Method B:
[0345] Intermediate 16 (1 g) was suspended in acetonitrile (12 mL),
then TEA (0.415 mL) was quickly added in order to obtain the free
base: the aspect of the slurry did not change as a new precipitate
of TEA-acetylmandelate salt was formed. After 30 minutes of
stirring, the mixture was treated with sodium triacetoxyborohydride
(0.6 g) plus formic acid (0.224 mL).
[0346] Meanwhile intermediate 4a (1 g) was dissolved in
acetonitrile (6 mL) and the so-obtained solution was quickly added
to the slurry and the resulting mixture was kept under stirring
conditions for 18 hours. The slurry was evaporated to small volume.
AcOEt (10 mL) was added to the so-obtained mixture and the
resulting solution was washed with aqueous 4% sodium hydrogen
carbonate (2.times.5 mL) and then with 5% sodium chloride solution
(5 mL). The organic layer was dried and evaporated to a white
foam.
[0347] Isopropyl alcohol (10 mL) was added and the mixture was
evaporated again to dryness. The resulting foam was, once again,
dissolved in isopropyl alcohol (8 mL) and treated drop-wise with a
solution of maleic acid (0.232 g) in isopropyl alcohol (2 mL).
After 30 minutes the mixture was seeded and precipitation occurred
in a few minutes. The slurry was stirred 1 hour at 20.degree. C.
and then isoctane (10 mL) was added dropwise over 5-10 minutes. The
resulting suspension was stirred at room temperature for 19 hours.
The solid was filtered and washed with isopropanol/isoctane 1/1 (5
mL) and dried in vacuo at 40.degree. C. for 18 hours giving the
title compound (0.639 g) as a white solid.
[0348] HPLC: Column X-Terra 4.6.times.100 mm, RP18 3.5 .mu.m;
mobile phase: eluant A: NH.sub.4HCO.sub.3 5 mM (pH=8)/CH.sub.3CN
90/10--eluant B: NH.sub.4HCO.sub.3 5 mM (pH=8)/CH.sub.3CN
10/90--Gradient: from 50% B to 100% B in 7.5 minutes; 100% B for
0.5 minutes then 50% B for 3 minutes; column temp. 40.degree. C.;
flow=1 mL/min; .lamda.=210 nm; retention times 4.15 minutes,
>99% a/a.
[0349] .sup.1H-NMR (d.sub.6-DMSO): .delta. (ppm) 7.98 (bs, 1H);
7.68 (bs, 2H); 7.21 (dd, 1H); 6.93 (dd, 1H); 6.81 (dt, 1H); 6.09
(s, 2H); 5.31 (q, 1H); 4.19 (dd, 1H); 3.93 (m, 1H); 3.74 (bm, 1H);
3.46 (m, 1H); 3.45 (bm, 1H); 3.30 (bm, 2H); 2.93 (bt, 1H); 2.79 (t,
1H); 2.73 (s, 3H); 2.73 (bm, 1H); 2.60 (bm, 1H); 2.35 (s, 3H); 2.23
(m, 2H); 2.12 (m, 1H); 2.04 (bd, 1H); 1.98 (bd, 1H); 1.84 (m, 1H);
1.64 (q, 1H); 1.56 (m, 1H); 1.46 (d, 3H).
[0350] MS (ES/+): m/z=629 [MH--HOOCCHCHCOOH].sup.+
Example 12
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (12a)
and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
(12b)
Method A:
[0351] Intermediate 13b (220 mg) was added to a solution of
intermediate 4a (504 mg) in anhydrous acetonitrile (10 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 15
minutes, then sodium triacetoxyborohydride (422 mg) was added. The
mixture was stirred at 23.degree. C. for 18 hours. The solution was
diluted with a 5% sodium hydrogen carbonate solution (5 mL) and
extracted with AcOEt (3.times.30 mL). The combined organic extracts
were dried and concentrated in vacuo to a residue which was
purified by flash chromatography (AcOEt/MeOH 9:1) to give three
fractions:
[0352] 1. example 12a (125 mg) as a white solid.
[0353] 2. mixture of example 12a and 12b (950 mg)
[0354] 3. example 12b (280 mg) as a white solid.
Method B:
[0355] Intermediate 4a (10.45 g) and sodium triacetoxyborohydride
(6.32 g) were added to a solution of intermediate 13b (4.35 g) in
anhydrous acetonitrile (200 mL) under a Nitrogen atmosphere. The
mixture was stirred at 23.degree. C. for 14 hours. The solution was
diluted with water (50 mL) and with a saturated solution of sodium
hydrogen carbonate (30 mL) and extracted with AcOEt (3.times.100
mL). The combined organic extracts were dried and concentrated in
vacuo to a residue which was purified by flash chromatography
(CH/AcOEt/MeOH 50:50:8) to give these fractions as white foams:
[0356] 1. mixture 12a and 12b (1 g) (ratio 12a:12b=75:25)
[0357] 2. mixture 12a and 12b (2.65 g) (ratio 12a:12b=50:50)
[0358] 3. example 12b (2.13 g)--(ratio 12a:12b=16:84)
[0359] 4. example 12b (1.4 g) (ratio 12a:12b=6:94)
[0360] 5. mixture of 12a and 12b (0.5 g) (ratio 12a:12b=30:70)
[0361] 6. example 12a (1.6 g) (ratio 12a:12b=95:5)
Example 12a
[0362] T.l.c.: AcOEt/MeOH 9:1, Rf=0.24.
[0363] MS (ES/+) m/z=629 [M+H].sup.+.
[0364] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6 mm.times.5;
mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from 60:40 to 10:90 in
5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN 10:90 for 10 min.;
flux=0.8 mL/min.; .lamda. 220 nm; retention time 9.28 minutes.
Example 12b
[0365] T.l.c.: AcOEt/MeOH 9:1, Rf=0.2.
[0366] MS (ES/+) m/z=629 [M+H].sup.+.
[0367] HPLC: Column Supelcosil ABZ Plus 25 cm.times.4.6 mm.times.5;
mobile phase NH.sub.4OAc 10 mmol/CH.sub.3CN from 60:40 to 10:90 in
5 min. then NH.sub.4OAc 10 mmol/CH.sub.3CN 10:90 for 10 min.;
flux=0.8 mL/min; .lamda.=220 nm; retention time 8.86 minutes.
Example 13
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride
[0368] A solution of example 12a (125 mg) in dry Et2O (3 mL) was
treated with hydrochloric acid (1M in Et2O--201 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated twice with Et2O/pentane 2:1
(2 mL) to give the title compound as a white solid (115 mg).
[0369] NMR (d.sub.6-DMSO): .delta. (ppm) 10.9-10.6 (bm, 1H); 7.99
(s, 1H); 7.76 (s, 2H); 7.36 (dt, 1H); 7.0 (dd, 1H); 6.92 (dt, 1H);
5.25 (bt, 1H); 5.05 (q, 1H); 3.98 (m, 2H); 3.67 (m, 2H); 3.58 (m,
1H); 3.44 (m, 1H); 3.2 (m, 2H); 2.9 (m, 2H); 2.53 (s, 3H); 2.22 (s,
3H); 2.4-2.1 (m, 6H); 1.73 (m, 1H); 1.56 (m, 1H); 1.56 (d, 3H). MS
(ES/+) m/z=629 [M+H-HCl].sup.+.
Example 14
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(R)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
hydrochloride
[0370] A solution of example 12b (280 mg) in dry Et2O (5 mL) was
treated with hydrochloric acid (1M in Et2O--473 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated twice with Et2O/pentane 2:1
(2 mL) to give the title compound as a white solid (245 mg).
[0371] NMR (d.sub.6-DMSO): .delta. (ppm) 11.05 (bs, 1H); 7.95 (s,
1H); 7.64 (s, 2H); 7.19 (dt, 1H); 6.9 (dd, 1H); 6.78 (dt, 1H); 5.28
(q, 1H); 4.16 (dd, 1H); 3.53 (m, 2H); 3.41 (m, 2H); 3.17 (t, 1H);
2.94 (m, 2H); 2.96-2.8 (m, 2H); 2.75 (t, 1H); 2.69 (s, 3H); 2.31
(s, 3H); 2.3-2.0 (m, 1H); 1.9 (m, 1H); 1.75 (q, 1H); 1.5 (m, 1H);
1.43 (d, 3H).
[0372] MS (ES/+) m/z=629 [M+H-HCl].sup.+.
Example 15
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (15a)
and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
(15b)
[0373] Intermediate 13a (250 mg) was added to a solution of
intermediate 5b (449 mg) in anhydrous acetonitrile (9 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 1 hour,
then sodium triacetoxyborohydride (282 mg) was added. The mixture
was stirred at 23.degree. C. for 16 hours. The solution was diluted
with a 5% sodium hydrogen carbonate solution (10 mL) and extracted
with AcOEt (3.times.30 mL). The combined organic extracts were
washed with brine (10 mL), dried and concentrated in vacuo to a
residue which was purified by flash chromatography (AcOEt/MeOH 8:2)
to give three fractions:
[0374] 1. example 15a (181 mg) as a white solid.
[0375] 2. mixture of example 15a and 15b (40 mg)
[0376] 3. example 15b (218 mg) as a white solid.
Example 15a
[0377] T.l.c.: AcOEt/MeOH 8:2, Rf=0.46.
[0378] MS (ES/+) m/z=629 [M+H].sup.+.
Example 15b
[0379] T.l.c.: AcOEt/MeOH 8:2, Rf=0.24.
[0380] NMR (d.sub.6-DMSO): .delta. (ppm) 1.45 (m, 1H); 1.47 (d,
3H); 1.65 (m, 1H); 1.70 (m, 1H); 1.85 (m, 1H); 1.9 (m, 1H); 1.95
(m, 1H); 2.00 (m, 1H); 2.05 (m, 1H); 2.25 (m, 2H); 2.34 (s, 3H);
2.65 (m, 1H); 2.77 (m, 1H); 2.80 (m, 1H); 2.81 (s, 3H); 3.40 (m,
1H); 3.41 (m, 1H); 3.46 (dd, 1H); 3.74 (m, 2H); 4.13 (dd, 1H); 5.33
(q, 1H); 6.74 (m, 1H); 6.88 (dd, 1H); 7.54 (s, 2H); 7.20 (dd, 1H);
7.93 (s, 2H).
[0381] MS (ES/+) m/z=629 [M+H].sup.+.
Example 16
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
(15b)
[0382] A solution of example 15b (218 mg) in dry Et2O (1 mL) was
treated with hydrochloric acid (1M in Et2O--380 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 1 hour, then the mixture was concentrated in
vacuo. The precipitate was triturated twice with pentane to give
the title compound as a white solid (195 mg).
[0383] NMR (d.sub.6-DMSO): .delta. (ppm) 10.60 (sb, 1H); 7.94 (s,
1H); 7.54 (s, 2H); 7.22 (dd, 1H); 6.93 (dd, 1H); 6.80 (td, 1H);
5.33 (q, 1H); 4.20 (bd, 1H); 3.98 (bd, 1H); 3.92 (m, 1H); 3.60 (m,
1H); 3.46 (m, 1H); 3.53 (m, 1H); 3.43 (m, 1H); 3.14 (bt, 1H); 2.96
(m, 1H); 2.86 (m, 1H); 2.85 (s, 3H); 2.6 (s, 3H); 2.73 (m, 1H);
2.2-2.35 (m, 2H); 2.19 (m, 1H); 2.15 (m, 1H); 2.16 (m, 1H); 1.95
(dd, 1H); 1.64 (dd, 1H); 1.58 (m, 1H); 1.50 (d, 3H).
Example 17
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide (17a)
and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
(17b)
[0384] Intermediate 13b (220 mg) was added to a solution of
intermediate 5b (500 mg) in anhydrous acetonitrile (10 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 30
minutes, then sodium triacetoxyborohydride (422 mg) was added. The
mixture was stirred at 23.degree. C. for 18 hours. The solution was
diluted with a 5% sodium hydrogen carbonate solution (5 mL) and
extracted with AcOEt (3.times.30 mL). The combined organic extracts
were washed with brine (10 mL), dried and concentrated in vacuo to
a residue which was purified by flash chromatography (AcOEt/MeOH
8:2) to give two fractions:
[0385] 1. example 17a (160 mg) as a white solid.
[0386] 2. example 17b (243 mg) as a white solid.
Example 17a
[0387] T.l.c.: AcOEt/MeOH 8:2, Rf=0.21.
[0388] NMR (d.sub.6-DMSO): .delta. (ppm) 1.50 (d, 3H); 1.53 (m,
1H); 1.71 (m, 1H); 1.72 (m, 1H); 1.75 (m, 1H); 1.81 (m, 1H); 1.88
(m, 1H); 1.94 (m, 1H); 2.09 (m, 1H); 2.19 (m, 2H); 2.26 (s, 3H);
2.64 (m, 1H); 2.71 (s, 3H); 2.76 (m, 1H); 2.93 (m, 1H); 3.08 (m,
1H); 3.15 (m, 1H); 3.27 (m, 1H); 3.53 (m, 1H); 3.74 (m, 2H); 3.88
(bm, 1H); 4.85 (dd, 1H); 5.27 (q, 1H); 6.84 (td, 1H); 6.94 (dd,
1H); 7.30 (dd, 1H); 7.69 (s, 2H); 7.95 (s, 1H).
Example 17b
[0389] T.l.c.: AcOEt/MeOH 8:2, Rf=0.13.
[0390] NMR (d.sub.6-DMSO): .delta. (ppm) 1.45 (d, 3H); 1.6-2.27
(bm, 10H); 2.3 (s, 3H); 2.61-2.97 (bm, 4H); 2.78 (s, 3H); 2.9 (bd,
1H); 3.4 (d, 2H); 3.7-3.9 (bm, 1H); 4.1 (dd, 1H); 5.27 (q, 1H);
6.72 (td, 1H); 6.84 (dd, 1H); 7.15-7.19 (dd, 1H); 7.5 (s, 2H); 7.89
(s, 1H).
Example 18
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
[1-(S)-(3,5-bis-trifluoromethyl-phenyl)-ethyl]-methylamide
[0391] A solution of example 17b (235 mg) in dry Et2O (4.2 mL) was
treated with hydrochloric acid (1M in Et2O--411 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated three times with pentane to
give the title compound as a white solid (243 mg).
[0392] NMR (d.sub.6-DMSO): .delta. (ppm) 10.88 (bs, 1H); 7.94 (s,
1H); 7.54 (s, 1H); 7.23 (dd, 1H); 6.93 (dd, 1H); 6.79 (td, 1H);
5.33 (q, 1H); 4.21 (dd, 1H); 3.99 (bs, 1H); 3.97 (m, 1H); 3.55 (m,
1H); 3.54-2.7 (m, 1H); 3.57 (m, 1H); 3.44 (m, 1H); 3.18 (t, 1H);
2.95 (m, 1H); 2.84 (s, 3H); 2.7 (t, 1H); 2.36 (s, 3H); 2.3 (m, 1H);
2.17 (m, 1H); 2.15 (q, 1H); 2.1 (m, 1H); 1.69 (q, 1H); 1.56 (m,
1H); 1.50 (d, 3H).
Examples 19
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-Pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide (19a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide (19b)
[0393] Intermediate 13a (40 mg) was added to a solution of
intermediate 14 (100 mg) in anhydrous acetonitrile (5 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 15
minutes, then sodium triacetoxyborohydride (90 mg) was added. The
mixture was stirred at 23.degree. C. for 20 hours. The solution was
diluted with a saturated sodium hydrogen carbonate solution (10 mL)
and extracted with AcOEt (3.times.50 mL). The combined organic
extracts were dried and concentrated in vacuo to a residue which
was purified by flash chromatography (AcOEt/MeOH 8:2) to give two
fractions:
[0394] 1. example 19a (25 mg)
[0395] 2. example 19b (40 mg).
Example 19a
[0396] T.l.c.: AcOEt/MeOH 8:2, Rf=0.36.
[0397] MS (ES/+) m/z=547 [M+H].sup.+.
Example 19b
[0398] T.l.c.: AcOEt/MeOH 8:2, Rf=0.2.
[0399] MS (ES/+) m/z=547 [M+H].sup.+.
Example 20
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide hydrochloride
[0400] A solution of example 19a (25 mg) in dry Et2O (1 mL) was
treated with hydrochloric acid (1M in Et2O--54 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated with Et2O/pentane 1:1 and
then pentane to give the title compound as a white solid (20
mg).
[0401] NMR (d.sub.6-DMSO): .delta. (ppm) 10.95 (bs, 1H); 7.44 (s,
2H); 7.35 (m, 2H); 7.00 (s, 1H); 6.85 (m, 1H); 5.2-4.8 (m, 1H);
4.4-4.2 (dd, 2H); 4.05-3.5 (m, 10H); 3.2-1.5 (m, 8H); 2.7 (s, 3H);
2.27 (s, 3H).
[0402] MS (ES/+) m/z=547 [M+H-HCl].sup.+.
Example 21
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aS)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide hydrochloride
[0403] A solution of example 19b (40 mg) in dry Et2O (1 mL) was
treated with hydrochloric acid (1M in Et2O--87 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated with Et2O/pentane 1:1 and
then pentane to give the title compound as a white solid (35
mg).
[0404] NMR (d.sub.6-DMSO): .delta. (ppm) 10.95 (bs, 1H); 7.44 (t,
1H); 7.28 (dd, 1H); 6.96 (dd, 1H); 6.93 (td, 1H); 6.89 (s, 2H);
4.49 (d, 1H); 4.19 (d, 1H); 4.16 (d, 1H); 3.97 (m, 2H); 3.6 (dd,
1H); 3.54 (m, 1H); 3.51 (dd, 1H); 3.46 (m, 1H); 3.19 (dd, 1H); 2.94
(m, 1H); 2.90 (s, 3H); 2.86 (dd, 1H); 2.37 (s, 3H); 2.26 (m, 1H);
2.24 (dd, 1H); 2.23 (dd, 1H); 2.17 (m, 1H); 1.96 (dd, 1H); 1.69
(dd, 1H); 1.58 (m, 1H).
[0405] MS (ES/+) m/z=547 [M+H-HCl].sup.+.
Examples 22
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexa
hydro-pyrrolo[1,2-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide (22a) and
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-
-a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide (22b)
[0406] Intermediate 13b (40 mg) was added to a solution of
intermediate 14 (100 mg) in anhydrous acetonitrile (5 mL) under a
Nitrogen atmosphere. The solution was stirred at r.t. for 15
minutes, then sodium triacetoxyborohydride (90 mg) was added. The
mixture was stirred at 23.degree. C. for 20 hours. The solution was
diluted with a saturated sodium hydrogen carbonate solution (10 mL)
and extracted with AcOEt (3.times.50 mL). The combined organic
extracts were dried and concentrated in vacuo to a residue which
was purified by flash chromatography (AcOEt/MeOH 8:2) to give two
fractions:
[0407] 1. example 22a (23 mg)
[0408] 2. example 22b (43 mg).
Example 22a
[0409] T.l.c.: AcOEt/MeOH 8:2, Rf=0.36.
[0410] MS (ES/+) m/z=547 [M+H].sup.+.
Example 22b
[0411] T.l.c.: AcOEt/MeOH 8:2, Rf=0.2.
[0412] MS (ES/+) m/z=547 [M+H].sup.+.
Example 23
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(R)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide hydrochloride
[0413] A solution of example 22a (23 mg) in dry Et2O (2 mL) was
treated with hydrochloric acid (1M in Et2O--46 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 1 hour, then the mixture was concentrated in
vacuo. The precipitate was triturated with pentane to give the
title compound as a white solid (25 mg).
[0414] NMR (d.sub.6-DMSO): .delta. (ppm) 10.77 (bs, 1H); 7.48 (t,
1H); 7.37 (dd, 1H); 7.14 (m, 2H); 7.03 (dd, 1H); 6.96 (td, 1H);
5.23 (m, 1H); 4.33 (d, 1H); 4.28 (d, 1H); 3.99 (m, 1H); 3.98 (m,
1H); 3.7 (dd, 1H); 3.63 (m, 1H); 3.6 (dd, 1H); 3.49 (m, 1H); 3.19
(t, 1H); 3.14 (dd, 1H); 2.93 (m, 1H); 2.71 (s, 3H); 2.4-2.2 (m,
2H); 2.35 (m, 1H); 2.27 (s, 3H); 2.22 (m, 1H); 2.18 (m, 1H); 2.17
(m, 1H); 1.75 (m, 1H); 1.6 (m, 1H).
[0415] MS (ES/+) m/z=547 [M+H-HCl].sup.+.
Example 24
2-(R)-(4-Fluoro-2-methyl-phenyl)-4-(S)-((8aR)-6-oxo-hexahydro-pyrrolo[1,2--
a]-pyrazin-2-yl)-piperidine-1-carboxylic acid
(3,5-dichloro-benzyl)-methylamide hydrochloride
[0416] A solution of example 22b (41 mg) in dry Et2O (1 mL) was
treated with hydrochloric acid (1M in Et2O--46 L) at 0.degree. C.
under a Nitrogen atmosphere. The resulting mixture was stirred at
0.degree. C. for 15 minutes, then the mixture was concentrated in
vacuo. The precipitate was triturated with Et2O/pentane 1:1 and
then pentane to give the title compound as a white solid (21
mg).
[0417] NMR (d.sub.6-DMSO): .delta. (ppm) 10.72 (bs, 1H); 7.44 (t,
1H); 7.30 (dd, 1H); 6.96 (dd, 1H); 6.91 (m, 1H); 6.89 (s, 2H); 4.49
(d, 1H); 4.21 (m, 1H); 4.16 (d, 1H); 3.98 (m, 1H); 3.94 (m, 1H);
3.58 (dd, 1H); 3.56 (m, 1H); 3.5 (dd, 1H); 3.44 (m, 1H); 3.17 (t,
1H); 2.95 (m, 1H); 2.90 (s, 3H); 2.88 (dd, 1H); 2.74 (dd, 1H); 2.37
(s, 3H); 2.26 (m, 2H); 2.18 (m, 1H); 2.17 (m, 1H); 2.16 (m, 1H);
1.94 (m, 1H); 1.72 (m, 1H); 1.58 (m, 1H).
[0418] MS (ES/+) m/z=547 [M+H-HCl].sup.+.
Examples 25
1-(4-Fluoro-2-methyl-phenyl)-4-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-a]pyrazi-
n-2-yl)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide (25a--anti) and
1-(4-Fluoro-2-methyl-phenyl)-4-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-a]pyraz-
in-2-yl)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide (25b--syn)
[0419] Intermediate 13b (10 mg) was added to a solution of
intermediate 21 (150 mg) in dry acetonitrile (1 mL) under a
nitrogen atmosphere. The mixture was stirred at 23.degree. C. for
30 minutes, then sodium triacetoxyborohydride (24 mg) was added.
The solution was stirred at 23.degree. C. for 16 hours, then washed
with a 5% sodium hydrogen carbonate solution (5 mL) and brine (5
mL). The organic layer was dried and concentrated in vacuo to a
residue which was purified by flash chromatography (AcOEt/MeOH 8:2)
to give three fractions:
[0420] 1. example 25a (C-2 and C-4 anti configuration--6.5 mg).
[0421] 2. example 25a+example 25b (5.5 mg).
[0422] 3. example 25b (C-2 and C-4 syn configuration--7.3 mg).
Example 25a
[0423] T.l.c.: AcOEt/MeOH 8:2, Rf=0.52.
[0424] MS (ES/+) m/z=615 [M+H].sup.+.
Example 25a
[0425] T.l.c.: AcOEt/MeOH 8:2, Rf=0.39.
[0426] MS (ES/+) m/z=615 [M+H].sup.+.
Example 26
1-(4-Fluoro-2-methyl-phenyl)-4-((8aR)-6-oxo-hexahydro-pyrrolo[1,2-a]pyrazi-
n-2-yl)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide hydrochloride
(25b--syn)
[0427] Example 25b (5.4 mg) in dry Et2O (0.5 mL) was treated with
hydrochloric acid (1M in Et2O--0.1 mL) and the resulting solution
was stirred at 0.degree. C. for 30 minutes. The solution was
concentrated in vacuo. The residue was triturated with Et2O (1 mL)
and pentane (1 mL) to give the title compound as a white solid (4
mg).
[0428] NMR (d.sub.6-DMSO): .delta. (ppm) 1.63 (m, 1H); 1.88 (mb,
1H); 2.09 (mb, 1H); 2.19 (m, 1H); 2.27 (s, 3H), 2.1-3.8 (13H); 3.11
(s, 3H); 3.95 (mb 1H), 4.02 (bd, 1H); 4.35 (sb, 1H); 4.94 (mb, 1H);
6.91 (dd, 1H); 6.73 (td, 1H); 7.55 (s, 2H); 7.93 (s, 1H); 7.10 (dd,
1H); 10.51 (bs, 1H).
Example 27
1-(4-Fluoro-2-methyl-phenyl)-4-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-a]pyrazi-
n-2-yl)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide (25b--syn)
[0429] A solution of intermediate 21 (63 mg) in anhydrous
acetonitrile (2 mL) was added to a solution of intermediate 13a (27
mg) in anhydrous acetonitrile (2 mL) under a nitrogen atmosphere.
The mixture was stirred at 23.degree. C. for 1 hour, then sodium
triacetoxyborohydride (49 mg) was added. The solution was stirred
at 23.degree. C. for 24 hours, then further sodium
triacetoxyborohydride (13.6 mg) was added and stirring was
continued for 7 days. The mixture was diluted with DCM and washed
with a saturated sodium hydrogen carbonate solution. The organic
layer was dried and concentrated in vacuo to a residue which was
purified by flash chromatography (AcOEt/MeOH 9:1) to give the title
compound (14 mg) as a white foam.
[0430] T.l.c.: AcOEt/MeOH 8:2, Rf=0.28.
[0431] NMR (d.sub.6-DMSO): .delta. (ppm) 1.52 (m, 1H); 1.65 (m,
2H); 1.75 (m, 1H); 1.95 (m, 1H); 2.0-2.2 (m, 2H); 2.06 (m, 1H); 2.1
(m, 1H); 2.23 (s, 3H); 2.46 (m, 1H); 2.69 (m, 1H); 2.82 (m, 1H);
2.9 (m, 1H); 2.92 (m, 1H); 2.96 (m, 1H); 3.07 (s, 3H); 3.2 (m, 1H);
3.48 (m, 1H); 3.78 (m, 1H); 4.14 (bd, 1H); 4.35 (bd, 1H); 4.54 (bd,
1H); 6.69 (td, 1H); 6.81 (dd, 1H); 7.04 (dd, 1H); 7.54 (s, 2H); 7.8
(s, 1H).
Example 28
1-(4-Fluoro-2-methyl-phenyl)-4-((8aS)-6-oxo-hexahydro-pyrrolo[1,2-a]pyrazi-
n-2-yl)-piperidine-2-carboxylic acid
(3,5-bis-trifluoromethyl-benzyl)-methyl-amide hydrochloride
(syn)
[0432] Hydrochloric acid (1M in Et2O--21.5 L) was added to a
solution of example 27 (12 mg) in dry Et2O (1 mL) previously cooled
to 0.degree. C. under a nitrogen atmosphere. The resulting mixture
was stirred at 0.degree. C. for 30 minutes. The solution was
concentrated in vacuo. The residue was triturated with pentane
(2.times.1 mL) to give the title compound as a white solid (12
mg).
[0433] NMR (d.sub.6-DMSO): .delta. (ppm) 1.62 (m, 1H); 1.87 (m,
1H); 1.91 (b, 1H); 2.06 (b, 1H); 2.1-2.4 (m, 2H); 2.16 (m, 1H);
2.25 (s, 3H); 2.5 (m, 1H); 2.56 (m, 1H); 2.6 (m, 1H); 2.7-3.8 (m,
5H); 2.95 (m, 1H); 3.1 (m, 1H); 3.9 (bd, 1H); 3.96 (bd, 1H); 4.24
(bm, 1H); 4.67 (bd, 1H); 6.81 (td, 1H); 6.82 (dd, 1H); 7.05 (dd,
1H); 7.54 (s, 2H); 7.81 (s, 1H);
[0434] MS (ES/+) m/z=615 [M+H-HCl].sup.+.
PHARMACY EXAMPLES
Pharmacy examples
A. Tablets
TABLE-US-00003 [0435] Active ingredient 10.0 mg PVP 9 mg
Microcrystalline Cellulose 266 mg Sodium Starch Glycolate 12 mg
Magnesium Stearate 3 mg Active ingredient 50 mg PVP 9 mg
Microcrystalline Cellulose 226 mg Sodium Starch Glycolate 12 mg
Magnesium Stearate 3 mg
[0436] The active ingredient is blended with the other excipients.
The blend can be compressed to form tablets using appropriate
punches. The tablets can be coated using conventional techniques
and coatings.
B. Capsules
TABLE-US-00004 [0437] Active ingredient 25.0 mg (1-100 mg)
Microcrystalline Cellulose qs
[0438] The active ingredient is blended with microcrystalline
cellulose and then filled into suitable capsules.
C) Injection
TABLE-US-00005 [0439] Active ingredient 2-20 mg/mL Buffer solution
pH 3.5(3.0-4.0) suitable for injection qs to 10 mL (e.g. citrate
buffer in sterile water for injection or NaCl 0.9%)
[0440] The formulation may be packaged in glass or plastic vials or
ampules. The formulation may be administered by bolus injection or
infusion, e.g. after dilution with D5W or 0.9% NaCl.
[0441] The affinity of the compound of the invention for NK.sub.1
receptor was determined using the NK.sub.1 receptor binding
affinity method measuring in vitro by the compounds' ability to
displace [3H]-substance P (SP) from recombinant human NK.sub.1
receptors expressed in Chinese Hamster Ovary (CHO) cell membranes.
The affinity values are expressed as negative logarithm of the
inhibition constant (Ki) of displacer ligands (pKi).
[0442] The pKi values obtained as the average of at least two
determinations with representative compounds of the invention are
within the range of 9.40 to 11.00.
* * * * *