U.S. patent application number 11/620359 was filed with the patent office on 2007-06-07 for pharmaceutically active pyrrolidine ester derivatives.
This patent application is currently assigned to APPLIED RESEARCH SYSTEMS ARS HOLDING N.V.. Invention is credited to Jerome Dorbais, Vincent Pomel, Anna Quattropani, Alexander Scheer, Matthias Schwarz.
Application Number | 20070129381 11/620359 |
Document ID | / |
Family ID | 8176843 |
Filed Date | 2007-06-07 |
United States Patent
Application |
20070129381 |
Kind Code |
A1 |
Schwarz; Matthias ; et
al. |
June 7, 2007 |
PHARMACEUTICALLY ACTIVE PYRROLIDINE ESTER DERIVATIVES
Abstract
The present invention is related to the use of pyrrolidine
esters of formula (I) for the treatment and/or prevention of
premature labor, premature birth and dysmenorrhea. In particular,
the present invention is related to the use of pyrrolidine esters
of formula (I) to modulate, notably to antagonise the oxytocin
receptor. The present invention is furthermore related to novel
pyrrolidine esters. ##STR1## X is selected from the group
consisting of CR.sup.6R.sup.7, NOR.sup.6, NNR.sup.6R.sup.7; R is
selected from the group comprising or consisting of C.sub.1-C.sub.6
alkyl, C.sub.2-C.sub.6 alkenyl, C.sub.2-C.sub.6 alkynyl, saturated
or unsaturated 3-8-membered cycloalkyl which may contain 1 to 3
heteroatoms selected of N, O, S, aryl, heteroaryl,
C.sub.1-C.sub.6-alkyl aryl, C.sub.1-C.sub.6-alkyl heteroaryl.
R.sup.1 is selected from the group comprising or consisting of
C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl,
C.sub.2-C.sub.6-alkynyl, aryl, heteroaryl, 3-8-membered cycloalkyl,
acyl, C.sub.1-C.sub.6-alkyl aryl, C.sub.1-C.sub.6-alkyl heteroaryl,
said cycloalkyl or aryl or heteroaryl groups may be fused with 1-2
further cycloalkyl or aryl or heteroaryl group.
Inventors: |
Schwarz; Matthias; (Thonex,
CH) ; Quattropani; Anna; (Geneve, CH) ;
Scheer; Alexander; (Versoix, CH) ; Dorbais;
Jerome; (Annecy, FR) ; Pomel; Vincent;
(Groisy, FR) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
APPLIED RESEARCH SYSTEMS ARS
HOLDING N.V.
Curacao
NL
|
Family ID: |
8176843 |
Appl. No.: |
11/620359 |
Filed: |
January 5, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10471290 |
Feb 23, 2004 |
7189754 |
|
|
PCT/EP02/03005 |
Mar 19, 2002 |
|
|
|
11620359 |
Jan 5, 2007 |
|
|
|
Current U.S.
Class: |
514/256 ;
514/343; 514/423; 544/333; 546/279.1; 548/531 |
Current CPC
Class: |
A61K 31/401 20130101;
A61P 15/06 20180101; C07D 207/22 20130101; C07D 401/10 20130101;
A61P 43/00 20180101; A61P 15/00 20180101; C07D 403/10 20130101 |
Class at
Publication: |
514/256 ;
514/343; 514/423; 544/333; 548/531; 546/279.1 |
International
Class: |
A61K 31/506 20060101
A61K031/506; A61K 31/4439 20060101 A61K031/4439; A61K 31/401
20060101 A61K031/401; C07D 403/02 20060101 C07D403/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 20, 2001 |
EP |
01106888.9 |
Claims
1. A pharmaceutical composition comprising a pyrrolidine ester
according to formula (I), or a pharmaceutically acceptable salt
thereof, ##STR23## as well as its geometrical isomers, its
optically active forms as enantiomers, diastereomers and its
racemate forms, as well as pharmaceutically acceptable salts
thereof, wherein X is selected from the group consisting of
C.sup.6R.sup.7, NO.sup.6, NNR.sup.6R.sup.7; R is selected from the
group consisting of C.sub.1-C.sub.6 alkyl, C.sub.2-C.sub.6 alkenyl,
C.sub.2-C.sub.6 alkynyl, aryl, C.sub.1-C.sub.6-alkyl aryl,
saturated or unsaturated 3-8-membered cycloalkyl, and
C.sub.1-C.sub.6-alkyl-saturated or unsaturated 3-8-membered
cycloalkyl; R.sup.1 is selected from the group consisting of
C.sub.1-C.sub.6-alkyl, aryl, heteroaryl, saturated or unsaturated
3-8-membered cycloalkyl, acyl, C.sub.1-C.sub.6-alkyl aryl, and
C.sub.1-C.sub.6-alkyl heteroaryl, wherein said cycloalkyl or aryl
or heteroaryl groups may be fused with 1-2 further cycloalkyl, aryl
or heteroaryl groups; R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are
independently from each other selected from the group consisting of
hydrogen, halogen, C.sub.1-C.sub.6-alkyl; R.sup.6 and R.sup.7 are
independently selected from the group consisting of hydrogen,
C.sub.1-C.sub.6 alkyl, C.sub.2-C.sub.6 alkenyl, C.sub.2-C.sub.6
alkynyl, C.sub.1-C.sub.6 alkoxy, C.sub.1-C.sub.6 thioalkoxy,
halogen, cyano, nitro, acyl, alkoxycarbonyl, aminocarbonyl, aryl,
C.sub.1-C.sub.6-alkyl aryl, C.sub.1-C.sub.6-alkyl, saturated or
unsaturated 3-8-membered cycloalkyl, and
C.sub.1-C.sub.6-alkyl-saturated or unsaturated 3-8-membered
cycloalkyl.
2. The pharmaceutical composition according to claim 1, wherein X
is NOR.sup.6 and R.sup.6 is selected from the group consisting of
H, C.sub.1-C.sub.6 alkyl, C.sub.2-C.sub.6 alkenyl, C.sub.2-C.sub.6
alkynyl, acyl, aryl, saturated or unsaturated 3-8-membered
cycloalkyl, C.sub.1-C.sub.6-alkyl aryl, wherein said cycloalkyl or
aryl groups may be fused with 1-2 further cycloalkyl or aryl
groups.
3. The pharmaceutical composition according to claim 2, wherein
R.sup.6 is H or CH.sub.3.
4. The pharmaceutical composition according to claim 1, wherein
R.sup.1 is a C.sub.1-C.sub.6-alkyl, C.sub.2-C.sub.6-alkenyl,
C.sub.2-C.sub.6-alkynyl, aryl, heteroaryl, saturated or unsaturated
3-8-membered cycloalkyl.
5. The pharmaceutical composition according to claim 4, wherein
R.sup.1 is a biphenyl.
6. The pharmaceutical composition according to claim 1, wherein X
is NOR.sup.6, R.sup.6 is H, a C.sub.1-C.sub.6-alkyl, or aryl or
C.sub.1-C.sub.6-alkyl aryl group and R.sup.1 is selected from the
group consisting of C.sub.1-C.sub.6-alkyl, aryl and
C.sub.1-C.sub.6-alkyl aryl.
7. The pharmaceutical composition according to claim 6, wherein
R.sup.6 is methyl, R is a C.sub.1-C.sub.6-alkyl group and R.sup.1
is a biphenyl.
8. A method of modulating an oxytocin receptor in vitro comprising
administering to one or more cells having an oxytocin receptor the
pharmaceutical composition according to claim 1.
9. The method according to claim 8, wherein said modulating
comprises blocking the oxytocin receptor or antagonising the
binding of oxytocin to its receptor.
10. A method of treating premature labor, premature birth, or
dysmenorrheal comprising administering to a patient in need thereof
an effective amount of the pharmaceutical composition of claim
1.
11. A pyrrolidine ester compound of formula (I'), or a
pharmaceutically acceptable salt thereof, ##STR24## wherein R is
selected from the group consisting of C.sub.1-C.sub.6 alkyl,
C.sub.1-C.sub.6 alkyl aryl, and 3-8-membered cycloalkyl and R.sup.1
is selected from the group consisting of a 1,1'-biphenyl, a
pyridinyl-phenyl and a pyrimidinyl-phenyl group.
12. A pyrrolidine ester compound according to claim 11, wherein R
is a methyl group.
13. A pyrrolidine ester compound according to claim 11, wherein
R.sup.1 is a 1,1'-biphenyl group.
14. A pyrrolidine ester compound according to claim 11, wherein
R.sup.1 is a 1,1'-biphenyl group which is substituted by 1 or 2
substituents selected from the group consisting of C.sub.1-C.sub.6
alkyl, C.sub.1-C.sub.6 alkoxy, halogen, and CN.
15. A pyrrolidine derivative according to claim 11, selected from
the group consisting of: Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(5-pyrimidinyl)benzoyl]-2-pyrrolidine-carb-
oxylate, Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(2-pyridinyl)benzoyl]-2-pyrrolidine-carbox-
ylate, and Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(3-methyl-2-pyridinyl)benzoyl]-2-pyrrolidi-
necarboxylate.
16. A medicament comprising the pyrrolidine derivative according to
claim 11.
17. A pharmaceutical composition comprising at least one
pyrrolidine derivative according to claim 11, and a
pharmaceutically acceptable carrier, diluent or excipient
thereof.
18. A process for preparing a compound according to claim 11,
comprising: reacting a compound of formula (III) ##STR25## wherein
X, R.sup.2-R.sup.5 are H, with a carboxylic acid or acyl chloride
of formulae (IVa) or (IVb) ##STR26##
19. The pharmaceutical composition of claim 11, wherein R is a
methyl group.
20. A method of treating and/or preventing premature labor,
premature birth or dysmenorrheal, comprising administering to a
patient in need thereof an effective amount of the pharmaceutical
composition of claim 1.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a division of U.S. Ser. No.
10/471,290, filed on Sep. 22, 2003 (371 completion date Feb. 23,
2004), which is a National Stage (371) of PCT/EP02/03005, filed on
Mar. 19, 2002, which claims priority to EP 01106888.9, filed on
Mar. 20, 2001.
FIELD OF THE INVENTION
[0002] The present invention is related to the use of pyrrolidine
esters of formula (I) for the treatment and/or prevention of
premature labor, premature birth and dysmenorrhea. In particular,
the present invention is related to the use of pyrrolidine esters
of formula (I) to modulate, notably to antagonise the oxytocin
receptor. The present invention is furthermore also related to
novel pyrrolidine esters.
BACKGROUND OF THE INVENTION
[0003] Oxytocin (OT) is a peptide hormone and causes the
contraction of the uterus of mammals during labor. The
corresponding oxytocin receptor belongs to the family of
G-protein-coupled receptors and is similar to V.sub.1a and V.sub.2
vasopressin receptors. OT receptors increase dramatically during
the course of pregnancy. The concentration of OT receptors has been
shown to correlate with spontaneous uterine activity (M. Maggi et
al. J. Clin. Endocrinol Metabol; 70; 1142, 1990). Premature labor,
though, and premature birth is undesired as it represents a major
cause of perinatal morbidity and mortality. Hence, the management
of preterm labor represents a significant problem in the field of
obstetrics.
[0004] In recent years, strong evidence has accumulated indicating
that the hormone oxytocin plays a major role in initiating labor in
mammals, notably in humans. Thereby, it is assumed that oxytocin
exerts said effect in a direct as well as an indirect way, by
contracting the uterine myometrium and by enhancing the synthesis
and release of contractile prostaglandins from the uterine
endometrium/decidua. These prostaglandins may furthermore play a
role in the cervical ripening process. This "up-regulation" of
oxytocin receptors and increased uterine sensitivity seems to be
due to trophic effects of rising plasma levels of estrogen towards
term. By down-regulating oxytocin, it is expected that both the
direct (contractile) and indirect (increased prostaglandin
synthesis) effects of oxytocin on the uterine could be blocked. An
oxytocin modulator, e.g. blocker or antagonists would likely be
more efficacious for treating preterm labor than current regimens.
Moreover, as oxytocin at term has only an effect on the uterus,
such an oxytocin modulator would have only few or no side
effect.
[0005] A further condition being related to oxytocin is
dysmenorrhea, which is characterised by cyclic pain associated with
menses during ovulatory cycles. Said pain is believed to result
from uterine contractions and ischemia, probably mediated by the
effect of prostaglandins produced in the secretory endometrium. By
blocking both the indirect and direct effects of oxytocin on the
uterus, an oxytocin antagonist is believed more efficacious for
treating dysmenorrhea than current regimens.
[0006] Some agents counteracting the action of oxytocin (OT) are
currently used in clinical studies. Such tocolytic agents (i.e.
uterine-relaxing agents) include beta-2-adrenergic agonists,
magnesium sulfate and ethanol. The leading beta-2-adrenergic
agonists is Ritodrine, which causes a number of cardiovascular and
metabolic side effects, including tachycardia, increased renin
secretion, hyperglycemia and reactive hypoglycemia in the infant.
Further beta-32-adrenergic agonists, including terbutaline and
albuterol have side effects similar to those of ritodrine.
Magnesium sulfate at plasma concentrations above the therapeutic
range of 4 to 8 mg/dL can cause inhibition of cardiac conduction
and neuromuscular transmission, respiratory depression and cardiac
arrest, thus making this agent unsuitable when renal function is
impaired. Ethanol is as effective as ritodrine in preventing
premature labor, but it does not produce a corresponding reduction
in the incidence of fetal respirator distress that administration
of ritodrine does.
[0007] The principal drawback to the use of peptide antagonists
including also atosiban is the problem of low oral bioavailability
resulting from intestinal degradation. Hence, they are administered
parenterally.
[0008] The development of nonpeptide ligands for pepetide hormone
receptors are expected to overcome this problem. The first to
report small molecule selective oxytocin antagonists was Merck.
Apart from cyclic hexapeptides, Merck suggested indanylpiperidines
and tolyl-piperazines as orally deliverable OT antagonists (Evans
et al. J. Med. Chem., 35, 3919 (1992). In WO 96/22775 and U.S. Pat.
No. 5,716,497 Merck reported benzoxazinylpiperidines or
benzoxazinones as OT receptor antagonists.
[0009] The objective of this invention is to provide substances
which more effectively down-regulate up to antagonizing--the
function of OT in disease states in animals, preferably mammals,
especially in humans. It is another purpose of this invention to
provide a method of antagonizing the functions of oxytocin in
disease states of mammals. It is also an objective of the present
invention to provide small molecule chemical compounds for the
modulation, preferably the dow-regulation or even antagonisation of
the oxytocin receptor. Moreover, it is an objective of the present
invention to provide methods for preparing said small molecule
chemical compounds. It is furthermore an objective of the present
invention to provide a new category of pharmaceutical formulations
for the treatment of preterm labor and dysmenorrhea, and/or
diseases mediated by the oxytocin receptor. It is finally an
objective of the present invention to provide a method of treating
and/or preventing disorders mediated by the oxytocin receptor, like
preterm labor and dysmenorrhea by antagonising the binding of
oxytocin to its receptor.
SUMMARY OF THE INVENTION
[0010] The present invention relates to use of pyrrolidine esters
of formula (I) for the treatment and/or prevention of premature
labor, premature birth and dysmenorrhea. In particular, the present
invention is related to the use of pyrrolidine esters of formula
(I) to modulate, notably to antagonise the oxytocin receptor. The
present invention is furthermore related to novel pyrrolidine
esters. ##STR2##
DETAILED DESCRIPTION OF THE INVENTION
[0011] The aforementioned objectives have been met according to the
independent claims. Preferred embodiments are set out within the
dependent claims which are incorporated herein.
[0012] The following paragraphs provide definitions of the various
chemical moieties that make up the compounds according to the
invention and are intended to apply uniformly throughout the
specification and claims unless an otherwise expressly set out
definition provides a broader definition.
[0013] "C.sub.1-C.sub.6-alkyl" refers to monovalent alkyl groups
having 1 to 6 carbon atoms. This term is exemplified by groups such
as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl,
tert-butyl, n-hexyl and the like.
[0014] "Aryl" refers to an unsaturated aromatic carboxyclic group
of from 6 to 14 carbon atoms having a single ring (e.g. phenyl) or
multiple condensed rings (e.g. naphthyl). Preferred aryl include
phenyl, naphthyl, phenantrenyl and the like.
[0015] "C.sub.1-C.sub.6-alkyl aryl" refers to C.sub.1-C.sub.6-alkyl
groups having an aryl substituent, including benzyl, phenethyl and
the like.
[0016] "Heteroaryl" refers to a monocyclic heteroaromatic, or a
bicyclic or a tricyclic fused-ring heteroaromatic group. Particular
examples of heteroaromatic groups include optionally substituted
pyridyl, pyrrolyl, furyl, thienyl, imidazolyl, oxazolyl,
isoxazolyl, thiazolyl, isothiazolyl, pyrazolyl, 1,2,3-triazolyl,
1,2,4-triazolyl, 1,2,3-oxadiazolyl, 1,2,4-oxadiazolyl,
1,2,5-oxadiazolyl, 1,3,4-oxadiazolyl, 1,3,4-triazinyl,
1,2,3-triazinyl, benzofuryl, [2,3-dihydro]benzofuryl,
isobenzofuryl, benzothienyl, benzotriazolyl, isobenzothienyl,
indolyl, isoindolyl, 3H-indolyl, benzimidazolyl,
imidazo[1,2-a]pyridyl, benzothiazolyl, benzoxazolyl, quinolizinyl,
quinazolinyl, pthalazinyl, quinoxalinyl, cinnolinyl, napthyridinyl,
pyrido[3,4-b]pyridyl, pyrido[3,2-b]pyridyl, pyrido[4,3-b]pyridyl,
quinolyl, isoquinolyl, tetrazolyl, 5,6,7,8-tetrahydroquinolyl,
5,6,7,8-tetrahydroisoquinolyl, purinyl, pteridinyl, carbazolyl,
xanthenyl or benzoquinolyl.
[0017] "C.sub.1-C.sub.6-alkyl heteroaryl" refers to
C.sub.1-C.sub.6-alkyl groups having a heteroaryl substituent,
including 2-furylmethyl, 2-thienylmethyl, 2-(1H-indol-3-yl)ethyl
and the like.
[0018] "Alkenyl" refers to alkenyl groups preferably having from 2
to 6 carbon atoms and having at least 1 or 2 sites of alkenyl
unsaturation. Preferable alkenyl groups include ethenyl
(--CH.dbd.CH.sub.2), n-2-propenyl (allyl,
--CH.sub.2CH.dbd.CH.sub.2) and the like.
[0019] "Alkynyl" refers to alkynyl groups preferably having from 2
to 6 carbon atoms and having at least 1-2 sites of alkynyl
unsaturation, preferred alkynyl groups include ethynyl
(--C.ident.--CH), propargyl (--CH.sub.2C.ident.--CH), and the
like.
[0020] "Acyl" refers to the group --C(O)R where R includes H,
"C.sub.1-C.sub.6-alkyl", "aryl", "heteroaryl",
"C.sub.1-C.sub.6-alkyl aryl" or "C.sub.1-C.sub.6-alkyl
heteroaryl".
[0021] "Acyloxy" refers to the group --OC(O)R where R includes H,
"C.sub.1-C.sub.6-alkyl", "aryl", "heteroaryl",
"C.sub.1-C.sub.6-alkyl aryl" or "C.sub.1-C.sub.6-alkyl
heteroaryl".
[0022] "Alkoxy" refers to the group --O-R where R includes
"C.sub.1-C.sub.6-alkyl" or "aryl" or "heteroaryl" or
"C.sub.1-C.sub.6-alkyl aryl" or "C.sub.1-C.sub.6-alkyl heteroaryl".
Preferred alkoxy groups include by way of example, methoxy, ethoxy,
phenoxy and the like.
[0023] "Alkoxycarbonyl" refers to the group --C(O)OR where R
includes "C.sub.1-C.sub.6-alkyl" or "aryl" or "heteroaryl" or
"C.sub.1-C.sub.6-alkyl aryl" or "C.sub.1-C.sub.6-alkyl
heteroaryl".
[0024] "Aminocarbonyl" refers to the group --C(O)NRR' where each R,
R' includes independently hydrogen or C.sub.1-C.sub.6-alkyl or aryl
or heteroaryl or "C.sub.1-C.sub.6-alkyl aryl" or
"C.sub.1-C.sub.6-alkyl heteroaryl".
[0025] "Acylamino" refers to the group --NR(CO)R' where each R, R'
is independently hydrogen or "C.sub.1-C.sub.6-alkyl" or "aryl" or
"heteroaryl" or "C.sub.1-C.sub.6-alkyl aryl" or
"C.sub.1-C.sub.6-alkyl heteroaryl".
[0026] "Halogen" refers to fluoro, chloro, bromo and iodo
atoms.
[0027] "Sulfonyl" refers to group "--SO.sub.2-R" wherein R is
selected from H, "aryl", "heteroaryl", "C.sub.1-C.sub.6-alkyl",
"C.sub.1-C.sub.6-alkyl" substituted with halogens e.g. an
--SO.sub.2--CF.sub.3 group, "C.sub.1-C.sub.6-alkyl aryl" or
"C.sub.1-C.sub.6-alkyl heteroaryl".
[0028] "Sulfoxy" refers to a group "--S(O)-R" wherein R is selected
from H, "C.sub.1-C.sub.6-alkyl", "C.sub.1-C.sub.6-alkyl"
substituted with halogens e.g. an --SO--CF.sub.3 group, "aryl",
"heteroaryl", "C.sub.1-C.sub.6-alkyl aryl" or
"C.sub.1-C.sub.6-alkyl heteroaryl".
[0029] "Thioalkoxy" refers to groups --S--R where R includes
"C.sub.1-C.sub.6-alkyl" or "aryl" or "heteroaryl" or
"C.sub.1-C.sub.6-alkyl aryl" or "C.sub.1-C.sub.6-alkyl heteroaryl".
Preferred thioalkoxy groups include thiomethoxy, thioethoxy, and
the like.
[0030] "Substituted or unsubstituted": Unless otherwise constrained
by the definition of the individual substituent given in the
present specification, the above set out groups, like "alkyl",
"alkenyl", "alkynyl", "aryl" and "heteroaryl" etc. groups may
optionally be substituted with from 1 to 5 substituents selected
from the group consisting of "C.sub.1-C.sub.6-alkyl",
"C.sub.1-C.sub.6-alkyl aryl", "C.sub.1-C.sub.6-alkyl heteroaryl",
"C.sub.2-C.sub.6alkenyl", "C.sub.2-C.sub.6alkynyl", primary,
secondary or tertiary amino groups or quarternary ammonium
moieties, "acyl", "acyloxy", "acylamino", "aminocarbonyl",
"alkoxycarbonyl", "aryl", "heteroaryl", carboxyl, cyano, halogen,
hydroxy, mercapto, nitro, sulfoxy, sulfonyl, alkoxy, thioalkoxy,
trihalomethyl and the like. Alternatively said substitution could
also comprise situations where neighboring substituents have
undergone ring closure, notably when viccinal functional
substituents are involved, thus forming e.g. lactams, lactons,
cyclic anhydrides, but also acetals, thioacetals, aminals formed by
ring closure for instance in an effort to obtain a protective
group.
[0031] "Pharmaceutically acceptable salts or complexes" refers to
salts or complexes of the below-identified compounds of formula (I)
that retain the desired biological activity. Examples of such salts
include, but are not restricted to acid addition salts formed with
inorganic acids (e.g. hydrochloric acid, hydrobromic acid, sulfuric
acid, phosphoric acid, nitric acid, and the like), and salts formed
with organic acids such as acetic acid, oxalic acid, tartaric acid,
succinic acid, malic acid, famaric acid, maleic acid, ascorbic
acid, benzoic acid, tannic acid, pamoic acid, alginic acid,
polyglutamic acid, naphthalene sulfonic acid, naphthalene
disulfonic acid, and polygalacturonic acid. Said compounds can also
be administered as pharmaceutically acceptable quaternary salts
known by a person skilled in the art, which specifically include
the quarternary ammonium salt of the formula
--NR,R',R''.sup.+Z.sup.-, wherein X, R', R'' is independently
hydrogen, alkyl, or benzyl, and Z is a counterion, including
chloride, bromide, iodide, --O-alkyl, toluenesulfonate,
methylsulfonate, sulfonate, phosphate, or carboxylate (such as
benzoate, succinate, acetate, glycolate, maleate, malate, fumarate,
citrate, tartrate, ascorbate, cinnamoate, mandeloate, and
diphenylacetate).
[0032] "Pharmaceutically active derivative" refers to any compound
that upon administration to the recipient, is capable of providing
directly or indirectly, the activity disclosed herein.
[0033] "Enantiomeric excess" (ee) refers to the products that are
obtained by an asymmetric synthesis, i.e. a synthesis involving
non-racemic starting materials and/or reagents or a synthesis
comprising at least one enantioselective step, whereby a surplus of
one enantiomer in the order of at least about 52% ee is yielded. In
the absence of an asymmetric synthesis, racemic products are
usually obtained that do however also have the inventive set out
activity as OTR antagonists.
[0034] It was now found that pyrrolidine ester derivatives
according to formula (I) are useful for the treatment and/or
prevention of preterm labor premature birth and dysmenorrhea of
mammals and in particular of humans. Specifically, the pyrrolidine
ester derivatives according to formula (I) are useful for the
treatment and/or prevention of disorders related to the oxytocin
function, i.e. disorders that are mediated by the oxytocin
receptor. Preferably, the compounds of formula (I) are suitable to
modulate, in particular to dow-regulate the OTR function and more
specifically to antagonise the oxytocin receptor When the oxytocin
receptor is bound by the compounds according to formula (I),
oxytocin is antagonised by being blocked from its receptor and is
therefore unable to exert its biologic or pharmacological
effects.
[0035] The compounds being suitable for the treatment and/or
prevention of preterm labor, premature birth and dysmenorrhea are
those of formula (I). ##STR3##
[0036] Formula (I) also comprises geometrical isomers, optically
active forms like enantiomers, diastereomers and racemate forms, as
well as pharmaceutically acceptable salts thereof.
[0037] Preferred pharmaceutically acceptable salts of the compound
I, are acid addition salts formed with pharmaceutically acceptable
acids like hydrochloride, hydrobromide, sulfate or bisulfate,
phosphate or hydrogen phosphate, acetate, benzoate, succinate,
fumarate, maleate, lactate, citrate, tartrate, gluconate,
methanesulfonate, benzenesulfonate, and para-toluenesulfonate
salts.
[0038] In said formula (I), X is selected from the group consisting
of CR.sup.6R.sup.7, NOR.sup.6, NNR.sup.6R.sup.7.
[0039] R is selected from the group comprising or consisting of
unsubstituted or substituted C.sub.1-C.sub.6 alkyl, unsubstituted
or substituted C.sub.2-C.sub.6 alkenyl, unsubstituted or
substituted C.sub.2-C.sub.6 alkynyl, unsubstituted or substituted
saturated or unsaturated 3-8-membered cycloalkyl which may contain
1 to 3 heteroatoms selected of N, O, S, unsubstituted or
substituted aryl, unsubstituted or substituted heteroaryl,
unsubstituted or substituted C.sub.1-C.sub.6-alkyl aryl,
unsubstituted or substituted C.sub.1-C.sub.6-alkyl heteroaryl.
[0040] R.sup.1 is selected from the group comprising or consisting
of unsubstituted or substituted C.sub.1-C.sub.6-alkyl,
unsubstituted or substituted C.sub.2-C.sub.6-alkenyl, unsubstituted
or substituted C.sup.2-C.sub.6-alkynyl, unsubstituted or
substituted aryl, unsubstituted or substituted heteroaryl,
unsubstituted or substituted saturated or unsaturated 3-8-membered
cycloalkyl, acyl, unsubstituted or substituted
C.sub.1-C.sub.6-alkyl aryl, unsubstituted or substituted
C.sub.1-C.sub.6-alkyl heteroaryl, said cycloalkyl or aryl or
heteroaryl groups may be fused with 1-2 further cycloalkyl or aryl
or heteroaryl group.
[0041] R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are independently
selected from each other from the group consisting of hydrogen,
halogen, C.sub.1-C.sub.6-alkyl. Preferably they are all
hydrogen.
[0042] R.sup.6 and R.sup.7 are independently selected from the
group comprising or consisting of hydrogen, unsubstituted or
substituted C.sub.1-C.sub.6 alkyl, unsubstituted or substituted
C.sub.2-C.sub.6 alkenyl, unsubstituted or substituted
C.sub.2-C.sub.6 alkynyl, unsubstituted or substituted alkoxy,
unsubstituted or substituted thioalkoxy, halogen, cyano, nitro,
acyl, alkoxycarbonyl, aminocarbonyl, unsubstituted or substituted
saturated or unsaturated 3-8-membered cycloalkyl which may contain
1 to 3 heteroatoms selected of N, O, S unsubstituted or substituted
aryl, unsubstituted or substituted heteroaryl, unsubstituted or
substituted C.sub.1-C.sub.6-alkyl aryl, unsubstituted or
substituted C.sub.1-C.sub.6-alkyl heteroaryl.
[0043] Alternatively, R.sup.6, R.sup.7 could form together with the
N atom to which they are attached a 3-8 membered substituted or
unsubstituted, saturated or unsaturated heterocyclic ring which may
contain 1-2 further heteroatoms selected from N, S and O and which
is optionally fused with an aryl, heteroaryl or 3-8 membered
saturated or unsaturated cycloalkyl ring.
[0044] Compounds of formula (I)--wherein R is H or alkyl--are
disclosed in WO 99/52868. The compounds claimed therein are said to
be inhibitors of metalloproteases.
[0045] Preferred pyrrolidine derivatives are those compounds
according to formula (I) wherein R is an unsubstituted or
substituted C.sub.1-C.sub.6 alkyl.
[0046] Particularly preferred pyrrolidine derivatives are those
compounds according to formula (I) wherein X is NOR.sup.6, and
R.sup.6 is selected from the group consisting of H, unsubstituted
or substituted C.sub.1-C.sub.6 alkyl unsubstituted or substituted
C.sub.2-C.sub.6 alkenyl, unsubstituted or substituted
C.sub.2-C.sub.6 alkynyl, unsubstituted or substituted acyl,
unsubstituted or substituted aryl, unsubstituted or substituted
heteroaryl, unsubstituted or substituted saturated or unsaturated
3-8-membered cycloalkyl, unsubstituted or substituted
C.sub.1-C.sub.6-alkyl aryl, unsubstituted or substituted
C.sub.1-C.sub.6-alkyl heteroaryl, said cycloalkyl or aryl or
heteroaryl groups may be used with 1-2 further cycloalkyl or aryl
or heteroaryl groups. Particularly preferred R.sup.6 is H or
CH.sub.3.
[0047] More preferred groups R.sup.1 are substituted or
unsubstituted C.sub.1-C.sub.6-alkyl, substituted or unsubstituted
C.sub.2-C.sub.6-alkenyl, unsubstituted or substituted
C.sub.2-C.sub.6-alkynyl, substituted or unsubstituted aryl,
substituted or unsubstituted heteroaryl, saturated or unsaturated
3-8-membered substituted or unsubstituted cycloalkyl and still more
preferred R.sup.1 are substituted or unsubstituted
C.sub.1-C.sub.6-alkyl or substituted or unsubstituted aryl. A
particularly preferred substituent R.sup.1 is a substituted or
unsubstituted biphenyl.
[0048] According to a most preferred embodiment, the pyrrolidine
derivatives according to formula I are those wherein X is
NOR.sup.6, R.sup.6 is H, a C.sub.1-C.sub.6-alkyl, e.g. a methyl
group, or aryl or C.sub.1-C.sub.6-alkyl aryl group and R.sup.1 is a
C.sub.1-C.sub.6-alkyl or aryl or C.sub.1-C.sub.6-alkyl aryl group.
Even more preferred are those pyrrolidine derivatives, wherein X is
NOR.sup.6, R.sup.6 is methyl, R is an unsubstituted or substituted
C.sub.1-C.sub.6-alkyl group, e.g. a methyl group and R.sup.1 is a
substituted or unsubstituted biphenyl.
[0049] The compounds of formula (I) may contain one or more
asymmetric centers and may therefore exist as enantiomers or
diastereoisomers. It is to be understood that the invention
includes both mixtures and separate individual isomers or
enantiomers of the compounds of formula (I). In a particularly
preferred embodiment the pyrrolidine derivatives according to
formula (I) are obtained in an enantiomeric excess of at least 52 %
ee, preferably of at least 92-98% ee, Also, E/Z isomers with regard
to pyrrolidine derivatives having residues X being
.dbd.CR.sup.6R.sup.7 whereby both R.sup.6R.sup.7 are different from
each other, and/or with regard to pyrrolidine derivatives having
residues X being .dbd.NOR.sup.6 or .dbd.NNR.sup.6R.sup.7 are
comprised by the present invention.
[0050] A further aspect of the present invention is related to the
use of the pyrrolidine derivatives according to formula (I) for the
preparation of pharmaceutical compositions for the treatment and/or
prevention of premature labor, premature birth, for stopping labor
prior to cesarean delivery and dysmenorrhea. Preferably, the
compounds according to formula (I) are suitable for the modulation
of the OT function, thus specifically allowing the treatment and/or
prevention of disorders which are mediated by the oxytocin
receptor. Said treatment involves the modulation--notably the down
regulation or the antagonisation--of the oxytocin receptor.
[0051] Still a further aspect of the present invention is related
to the actually novel pyrrolidine compounds of formula (I). Said
compounds have the formula (I') ##STR4##
[0052] In formula (I'), R is selected from C.sub.1-C.sub.6 alkyl,
C.sub.1-C.sub.6 alkyl aryl, C.sub.1-C.sub.6 alkyl heteroaryl,
3-8-membered cycloalkyl. R.sup.1 is selected from an unsubstituted
or substituted 1,1'-biphenyl, pyridinyl-phenyl or
pyrimidinyl-phenyl group.
[0053] More preferred is R being a C.sub.1-C.sub.4 alkyl, i.e. a
methyl, ethyl, propyl or butyl or group, most preferred a methyl
group.
[0054] More preferred R.sup.1 is a 1,1'-biphenyl group which is
substituted by 1 or 2 moieties selected from the group consisting
of C.sub.1-C.sub.6 alkyl, C.sub.1-C.sub.6 alkoxy, halogen, CN. Most
preferred is a methyl group.
[0055] Specific compounds of formula (I') are the following: [0056]
Methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbon-
yl]-2-pyrrolidinecarboxylate [0057] Methyl
(2S,4EZ)-1-([1,1'-biphenyl]-4-ylcarbonyl)-4-(methoxyimino)-2-pyrrolidine--
carboxylate [0058] Methyl
(2S,4E)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate [0059] Methyl
(2S,4Z)-4-(methexyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate [0060] Methyl
(2S,4EZ)-1-[(2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-p-
yrrolidinecarboxylate [0061] Methyl
(2S,4Z)-1-[(2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-py-
rrolidinecarboxylate [0062] Methyl
(2S,4E)-1-[(2'-chloro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-py-
rrolidinecarboxylate [0063] Methyl
(2S,4EZ)-1-[(2'-cyano[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-py-
rrolidinecarboxylate [0064] Methyl
(2S,4EZ)-4-(methoxyimino)-1-{[2'-(trifluoromethyl)[1,1'-biphenyl
-4-yl]carbonyl}-2-pyrrolidinecarboxylate [0065] Methyl
(2S,4EZ)-1-[(2'-ethoxy[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-p-
yrrolidinecarboxylate [0066] Methyl
(2S,4EZ)-1-[(2',6'-dimethyl[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino-
)-2-pyrrolidinecarboxylate [0067] Methyl
(2S,4EZ)-1-[(2',3-dimethyl[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-
-2-pyrrolidinecarboxylate [0068] Methyl
(2S,4EZ-1-[(3-methyl[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-pyr-
rolidinecarboxylate [0069] Methyl
(2S,4EZ)-1-[(3',4'-dichloro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino-
)-2-pyrrolidinecarboxylate [0070] Ethyl
(2S,4EZ)-1-([1,1'-biphenyl]-4-ylcarbonyl)-4-(methoxyimino)-2-pyrrolidinec-
arboxylate sec-butyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate [0071] Cyclopentyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate [0072] Methyl
(2S,4EZ)-1-[(4'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-p-
yrrolidinecarboxylate [0073] Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(5-pyrimidinyl)benzoyl]-2-pyrrolidinecarbo-
xylate [0074] Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(2-pyridinyl)benzoyl]-2-pyrrolidinecarboxy-
late [0075] Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(3-methyl-2-pyridinyl)benzoyl]-2-pyrrolidi-
necarboxylate
[0076] The pyrrolidine derivatives exemplified in this invention
can be prepared from readily available starting materials using the
following general methods and procedures. It will be appreciated
that where typical or preferred experimental conditions (i.e.
reaction temperatures, time, moles of reagents, solvents, etc.) are
given, other experimental conditions can also be used unless
otherwise stated. Optimum reaction conditions may vary with the
particular reactants or solvents used, but such conditions can be
determined by one skilled in the art by routine optimisation
procedures.
[0077] Generally, the pyrrolidine derivatives according to the
general formula (I) could be obtained by several processes, using
both solution-phase and solid-phase chemistry protocols. Depending
on the nature of the R- and X-moieties, certain synthetic
approaches will, in some instances, be preferred over others, and
it is assumed that the choice of the most suitable process will be
evident to the practitioner skilled in the art.
[0078] According to one process, pyrrolidine derivatives according
to the general formula (I), whereby the substituents X, R and
R.sup.1-5 are as above defined, are prepared from the corresponding
suitably N-protected 4-substituted pyrrolidine derivatives II,
whereby the substituents X, R and R.sup.1-5 are as above defined,
by solution-phase chemistry protocols such as described in the
Examples and shown in Scheme 1, below. Removal of the N-protecting
group of II, using an appropriate deprotection agent (e.g. TFA,
piperidine H.sub.2/Pd/C) under standard conditions for
N-deprotection well known to the person skilled in the art,
produces derivatives of formula (III). These can be treated with
acylating agents of general formula (IV), whereby the substituent
R.sup.1 is as above defined, while Y could be any appropriate
leaving group. Preferred acylating agents IV are acid chlorides
(IVa), used in conjunction with a tertiary amine base, or
carboxylic acids (IVb), used in conjunction with an appropriate
peptide coupling agents, such as e.g. DIC, EDC, TBTU, DECP, or
others, to yield the pyrrolidine ester products of general formula
(I), with X, R and R.sup.1-5 being as above defined. ##STR5##
[0079] Pyrrolidine ester compounds of formula (II), whereby the
substituents X, R and R.sup.1-5 are as above defined, are obtained
from the corresponding pyrrolidine carboxylic acids V, and alcohols
VI, according to any of the standard methods well know to the
person skilled in the art for transforming a carboxylic acid into
an ester, e.g. those described in the Examples and shown in Scheme
2. The choice of the best reagent and reaction conditions will
depend on the nature of the X- and R-groups, and of the
N-protection group, as will be obvious to the practitioner skilled
in the art. ##STR6##
[0080] Intermediate compounds of formula V, whereby the substituent
X is CR.sup.6R.sup.7, and R.sup.6 and R.sup.7 are as above defined
(i.e. compounds of formula Va), may be prepared from compounds of
general formula VI by Wittig-type reactions with anions of
phosphoranes such as VIIa and/or of phosphonates such as VIIb,
followed by saponification of the ester function using standard
synthetic techniques, as hereinafter described in the Examples and
shown in Scheme 3 ##STR7##
[0081] Intermediate compounds of formula V, wherein the substiuent
X is NOR.sup.6 or NNR.sup.6R.sup.7 and R.sup.6 and R.sup.7 are as
above defined (i.e. compounds of formula Vb and Vc), may be
prepared from compounds of general formula (IX) by reaction with
substituted hydroxylamines Xb and/or substituted hydrazines and/or
hydrazides Xc using standard synthetic techniques as hereinafter
described in the Examples and shown in Scheme 4. Compounds of
formula Xa are commercially available or prepared by standard
synthetic techniques as hereinafter described in the Examples.
##STR8##
[0082] The intermediate compounds of general formulae VI and/or IX
may be prepared from commercially available, suitably N-protected
(e.g. Boc) 4-hydroxyprolines XI, by a reaction sequence consisting
of oxidation and, if appropriate, methylation, using standard
synthetic techniques as hereinafter described in the Examples and
illustrated in Scheme 5. ##STR9##
[0083] A further, alternative approach of preparing the compounds
of the present invention is depicted in Scheme 6. Following to this
process the pyrrolidine derivatives--whereby the substituents X, R
and R.sup.1-5 are as above defined--are prepared from compounds of
formula XII, using the synthetic techniques as outlined in Schemes
3 and 4. As further shown in Scheme 6, compounds of formula XII may
be obtained from compounds of formula (Ia) through transformation
of the methyloxime into the ketone moiety, e.g. uder mild
hydrolysis conditions as described hereinafter in the Examples.
This present synthetic strategy is most preferred where X is NOH or
NN.sup.6R.sup.7, whereby the substituents R.sup.6 and R.sup.7 are
as above defined. ##STR10##
[0084] According to yet another process, pyrrolidine ester
derivatives of general formula (I).sup.X can be interconverted
(transformed) to pyrrolidine ester derivatives of general formula
(I).sup.Y by a reaction sequence comprising saponification and
re-esterification with alcohols VI.sup.Y, using standard conditions
well known to the person skilled in the art, as described
hereinafter in the Examples and illustrated in Scheme 7.
##STR11##
[0085] R.sup.X and R.sup.Y are as above defined for R, but are
different from each other for the purpose of the
transesterification.
[0086] According to yet another process, pyrrolidine ester
derivatives according to the general formula (I) whereby the
substituents X, R and R.sup.1-5 are as above defined, are prepared
from the corresponding suitably N-protected 4-substituted
pyrrolidine carboxylic acid derivatives V, whereby the substituent
X is above defined, by a solid-phase protocol such as described in
the examples and shown in Scheme 8, below, The N-Boc-protected
4-substituted pyrrolidine derivative V is reacted with a resin
carrying a linker prone to cleavage by nucelophiles, e.g. with
Kaiser oxime resin, using standard carbodiimide-mediated coupling
conditions well known to the practitioner skilled in the art.
Boc-deprotection with dilute TFA in DCM, or with BF.sub.3.OEt.sub.2
in dilute HOAc in DCM, affords compounds of formula XVI. The latter
compound can be treated with acylating agents of general formula
(IV), whereby the substituent R.sup.1 is as above defined, and Y
could be an appropriate leaving group. Preferred acylating agents
IV are acid chlorides (IVa), used in conjunction with a tertiary
amine base, or carboxylic acids (IVb), used in conjunction with a
peptide coupling agent, such as e.g. DIC, EDC, TBTU, DECP, or
others, to yield products of general formula XVII.
[0087] In order to obtain the final compounds of general formula
(I), the linkage to the resin is cleaved by prolonged treatment
with alcohols VI, and a tertiary, non-nucleophilic amine base, such
as TEA, DIEA, DBU, or others. The circles in Scheme 8 symbolize the
resin beads to which the corresponding compounds are linked during
the solid phase synthesis. Other derivatives of formula (I) are
prepared using known modifications to, or variations of, the Scheme
8 reaction sequence. Further to the above mentioned Kaiser oxime
resin, other suitable reagents, notably resins known to a person
skilled in the art, could be employed for the solid-phase synthesis
of compounds of general formula (I). ##STR12##
[0088] The reaction sequences outlined in the above Schemes provide
enantiomerically pure compounds of formula (I), if enantiomerically
pure starting materials are used. (R)- as well as (S)-enantiomers
can be obtained depending upon whether (R)- or (S-forms of
commercially available compounds of formulas IV, V, X, and/or VI
were used as the starting materials.
[0089] However, the reaction sequences outlined in the above
Schemes usually provides mixtures of (E)- and (Z)-isomers with
respect to the substituents on the exocyclic double bond of the
pyrrolidine ring. In all cases studied, these (E)/(Z)-isomers could
be separated by standard chromatography techniques well known to
the person skilled in the art, such as by reversed phase
high-pressure liquid chromatography (HPLC) or silica gel flash
chromatography (FC). The assignment of the absolute configuration
of the exocyclic double bond was performed using NMR-techniques
well described in the literature as will be known to the
practitioner skilled in the art (for configurational assignments of
e.g. oxime functionalities, see e.g. E. Breitmaier, W. Voelter
Carbon-13 NMR Spectroscopy, 3rd Ed, VCH, 1987, p. 240).
[0090] According to a further general process, compounds of formula
(I) can be converted to alternative compounds of formula (I),
employing suitable interconversion techniques such as hereinafter
described in the Examples.
[0091] If the above set out general synthetic methods are not
applicable for obtaining compounds according to formula (I) and/or
necessary intermediates for the synthesis of compounds of formula
(I), suitable methods of preparation known by a person skilled on
the art should be used. In general, the synthesis pathways for any
individual compound of formula (I) will depend on the specific
substitutents of each molecule and upon the ready availability of
intermediates necessary; again such factors being appreciated by
those of ordinary skill in the art. For all the protection,
deprotection methods, see Philip J. Kocienski, in "Protecting
Groups", Georg Thieme Veriag Stuttgart, New York, 1994 and,
Theodora W. Greene and Peter C. M. Wuts in "Protective Groups in
Organic Synthesis", Wiley-Interscience, 1991.
[0092] Compounds of this invention can be isolated in association
with solvent molecules by crystallization from evaporation of an
appropriate solvent. The pharmaceutically acceptable acid addition
salts of the compounds of formula (I), which contain a basic
center, may be prepared in a conventional manner. For example, a
solution of the free base may be treated with a suitable acid,
either neat or in a suitable solution, and the resulting salt
isolated either by filtration or by evaporation under vacuum of the
reaction solvent. Pharmaceutically acceptable base addition salts
may be obtained in an analogous manner by treating a solution of
compound of formula (I) with a suitable base. Both types of salt
may be formed or interconverted using ion-exchange resin
techniques.
[0093] If the above set out general synthetic methods are not
applicable for the obtention of compounds of formula (I), suitable
methods of preparation known by a person skilled in the art should
be used.
[0094] When employed as pharmaceuticals, the pyrrolidine
derivatives of the present invention are typically administered in
the form of a pharmaceutical composition. Hence, pharmaceutical
compositions comprising a compound of formula (I) and a
pharmaceutically acceptable carrier, diluent or excipient therefore
are also within the scope of the present invention. A person
skilled in the art is aware of a whole variety of such carrier
diluent or excipient compounds suitable to formulate a
pharmaceutical composition. Also, the present invention provides
compounds for use as a medicament. In particular, the invention
provides the compounds of formula (I) for use as antagonists of the
oxytocin receptor, for the treatment or prevention of disorders
mediated by the oxytocin receptor in mammals, notably of humans,
either alone or in combination with other medicaments, e.g. in
combination with a further OT antagonist.
[0095] The compounds of the invention, together with a
conventionally employed adjuvant, carrier, diluent or excipient may
be placed into the form of pharmaceutical compositions and unit
dosages thereof, and in such form may be employed as solids, such
as tablets or filled capsules, or liquids such as solutions,
suspensions, emulsions, elixirs, or capsules filled with the same,
all for oral use, or in the form of sterile injectable solutions
for parenteral (including subcutaneous use). Such pharmaceutical
compositions and unit dosage forms thereof may comprise ingredients
in conventional proportions, with or without additional active
compounds or principles, and such unit dosage forms may contain any
suitable effective amount of the active ingredient commensurate
with the intended daily dosage range to be employed.
[0096] When employed as pharmaceuticals, the pyrrolidine
derivatives of this invention are typically administered in the
form of a pharmaceutical composition. Such compositions can be
prepared in a manner well known in the pharmaceutical art and
comprise at least one active compound. Generally, the compounds of
this invention are administered in a pharmaceutically effective
amount. The amount of the compound actually administered will
typically be determined by a physician, in the light of the
relevant circumstances, including the condition to be treated, the
chosen route of administration, the actual compound administered,
the age, weight, and response of the individual patient, the
severity of the patient's symptoms, and the like.
[0097] The pharmaceutical compositions of these inventions can be
administered by a variety of routes including oral, rectal,
transdermal subcutaneous, intravenous, intramuscular, and
intranasal. Depending on the intended route of delivery, the
compounds are preferably formulated as either injectable or oral
compositions. The compositions for oral administration can take the
form of bulk liquid solutions or suspensions, or bulk powders. More
commonly, however, the compositions are presented in unit dosage
forms to facilitate accurate dosing. The term "unit dosage forms"
refers to physically discrete units suitable as unitary dosages for
human subjects and other mammals, each unit containing a
predetermined quantity of active material calculated to produce the
desired therapeutic effect, in association with a suitable
pharmaceutical excipient. Typical unit dosage forms include
prefilled, premeasured ampoules or syringes of the liquid
compositions or pills, tablets, capsules or the like in the case of
solid compositions. In such compositions, the pyrrolidine compound
is usually a minor component (from about 0.1 to about 50% by weight
or preferably from about 1 to about 40% by weight) with the
remainder being various vehicles or carriers and processing aids
helpful for forming the desired dosing form.
[0098] Liquid forms suitable for oral administration may include a
suitable aqueous or nonaqueous vehicle with buffers, suspending and
dispensing agents, colorants, flavors and the like. Solid forms may
include, for example, any of the following ingredients, or
compounds of a similar nature: a binder such as microcrystalline
cellulose, gum tragacanth or gelatine; an excipient such as starch
or lactose, a disintegrating agent such as alginic acid, Primogel,
or corn starch; a lubricant such as magnesium stearate; a glidant
such as colloidal silicon dioxide; a sweetening agent such as
sucrose or saccharin; or a flavoring agent such as peppermint,
methyl salicylate, or orange flavoring.
[0099] Injectable compositions are typically based upon injectable
sterile saline or phosphate-buffered saline or other injectable
carriers known in the art. As above mentioned, the pyrrolidine
derivatives of formula (I) in such compositions is typically a
minor component, frequently ranging between 0.05 to 10% by weight
with the remainder being the injectable carrier and the like.
[0100] The above described components for orally administered or
injectable compositions are merely representative. Further
materials as well as processing techniques and the like are set out
in Part 8 of Remington's Pharmaceutical Sciences, 17.sup.th
Edition, 1985, Marck Publishing Company, Easton, Pa., which is
incorporated herein be reference.
[0101] The compounds of this invention can also be administered in
sustained release forms or from sustained release drug delivery
systems. A description of representative sustained release
materials can also be found in the incorporated materials in
Remington's Pharmaceutical Sciences.
[0102] In the following the present invention shall be illustrated
by means of some examples which are not construed to be viewed as
limiting the scope of the invention. The HPLC, NMR and MS data
provided in the examples described below were obtained as followed.
The following abbreviations are hereinafter used in the
accompanying examples: min (minute), hr (hour), g (gram), mmol
(millimole), m.p. (melting point), eq (equivalents), mL
(milliliter), .mu.L (microliters), mL (milliliters), ACN
(Acetonitrile), DBU (Diazabicyclo [5.4.0]undec-7-ene), DIEA
(Diisopropylethylamine), CDCl.sub.3 (deuterated chloroform), cHex
(Cyclo-hexanes), DCM (Dichloromethane), DECP
(Diethylcyanophosphonate), DIC (Diisopropyl carbodiimide), DMAP
(4-Dimethylaminopyridine) DMF (Dimethylform-amide), DMSO
(Dimethylsulfoxide), DMSO-d.sub.6 (deuterated dimrethylsul-foxide),
EDC (1-(3-Dimethyl-amino-propyl)-3-ethylcarbodiimide), EtOAc (Ethyl
acetate), Et.sub.2O (Diethyl ether), HOBt (1-Hydroxybenzotriazole),
K.sub.2CO.sub.3 (potassium carbonate), NaH (Sodium hydride),
NaHCO.sub.3 (Sodium bicarbonate), nBuLi (n Butyllithium), TBTU
(O-Benzotriazolyl-N,N,N',N'-tetra-methyluronium-tetrafluoroborate),
TEA (Triethylamine), TFA (Trifluoro-acetic acid), THF
(Tetrahydrofuran), MgSO.sub.4 (Magnesium sulfate), PetEther
(Petroleum ether), rt (room temperature).
EXAMPLES
Intermediate 1:
(2S)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid
[0103] Commercial
(2S,4R)-1-(tert-butoxycarbonyl)-4-hydroxy-2-pyrrolidinecarboxylic
acid (30 g, 0.13 mol) was dissolved in acetone (1500 ml). A
mechanical stirrer was placed in the flask and the solution stirred
vigorously. A freshly made solution of 8N chromic acid was prepared
by dissolving chromium trioxide (66.7 g, 0.667 mol) in water (40
ml), adding concentrated sulphuric acid (53.33 ml) and adding
enough water to bring the solution volume to 115 ml. The 8N chromic
acid solution (115 ml) was then added dropwise over a period of 30
minutes with continued vigorous stirring, the reaction's exotherm
being maintained at the optimal temperature of 25.degree. C. by the
use of an ice bath. After the complete addition of the chromic
acid, the reaction mixture was stirred for a further 15
minutes--maintaining the optimal temperature of 25.degree. C. The
reaction mixture was then quenched by the addition of methanol (20
ml). Exotherm controlled by the use of an ice bath and, if
necessary, direct addition of a small amount of crushed ice to the
reaction mixture itself. The reaction mixture was filtered through
a Celite pad and then concentrated in vacuo. The resulting acidic
solution was then extracted with ethyl acetate (3.times.300 ml) and
the combined organic layers washed with brine (2.times.100 ml).
Organics then dried with magnesium sulfate and concentrated in
vacuo. Crude product recrystallised from ethyl acetate to give the
white crystalline product,
(2S)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid
(22.55 g, 76%). The antipodal intermediate,
(2R)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid,
was made according to the same protocol, starting from commercial
(2R,4S)-1-(tert-butoxycarbonyl)-4-hydroxy-2-pyrrolidinecarboxylic
acid.
[0104] 1H NMR (360 MHz, CDCl3): 1.4 (m, 9H), 2.5-3.0 (m, 2H),
3.7-3.9 (m, 2H), 4.75 (dd, 1H)
Intermediate 2: 1-tert-butyl 2-methyl
(2S)-4-oxo-1,2-pyrrolidinedicarboxylate
[0105] A solution of
(2S)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid (1
g, 4.3 mmol) in a 1:1 mixture of methanol and toluene (60 ml) was
made. Trimethylsilyl diazomethane (6.5 ml of a 2M solution in
hexanes, 13 mmol) was then added dropwise to the stirred solution
at room temperature under nitrogen. After completion of the
evolution of nitrogen gas, the resulting yellow solution was
evaporated in vacuo, and the residue filtered through a pad of
silica gel, eluting with ethyl acetate. Removal of solvent from the
filtrate gave a yellow oil (1.05 g, near quantitative yield).
[0106] .sup.1H NMR (400 MHz, CDCl.sub.3): 1.4 (m, 9H), 2.5 (m, 1H),
2.8-2.9 (m, 1H) 3.7 (s, 3H), 3.9 (m, 2H), 4.6-4.8 (m, 1H).
Intermediate 3: 1-tert-butyl 2-methyl
(2S,4EZ)-4-(chloromethylene)-1,2-pyrrolidinedicarboxylate
[0107] Chloromethyltriphenylphosphonium iodide (270 mg, 0.62 mmol)
was added to a solution of potassium tert-butoxide (67 mg, 0.59
mmol) in anhydrous diethyl ether (5 ml) under nitrogen and the
resulting bright yellow mixture stirred for 30 minutes at ambient
temperature. The reaction was then cooled to 0.degree. C. and a
solution of 1-tert-butyl 2-methyl
(2S)-4-oxo-1,2-pyrrolidinedicarboxylate (100 mg, 0.41 mmol in 2 ml
anhydrous diethyl ether) was added dropwise. The reaction was then
warmed to room temperature and stirred for 30 minutes before adding
saturated aqueous ammonium chloride solution (0.5 ml). The organic
layer was removed in vacuo, and the aqueous washed with diethyl
ether (3.times.5 ml). The combined organic layers were dried with
brine and magnesium sulfate before filtering and removal of
solvent. The desired product was isolated by silica gel
chromatography, eluting with 15% ethyl acetate in hexanes to give
105 mg (93% yield) as a off-white wax,
[0108] .sup.1H NMR (400 MHz, CDCl.sub.3): 1.4 (9H, m), 2.6-2.75 (m,
1H), 2.8-3.0 (m, 1H), 3.65 (s, 3H), 4.1 (m, 2H), 4.4-4.5 (m, 1H)
5.9-6.0 (m, 1H).
Intermediate 4: 1-tert-butyl 2-methyl
(2-4-methylene-1,2-pyrrolidinedicarboxylate
[0109] Methyltriphenylphosphonium bromide (22 g, 61.6 mmol) was
added to a solution of potassium tert-butoxide (6.5 g, 57.6 mmol)
in anhydrous diethyl ether (450 ml) at 0.degree. C. under nitrogen
and the resulting bright yellow mixture stirred for 30 minutes. A
solution of 1-tert-butyl 2-methyl
(2S)-4-oxo-1,2-pyrrolidinedicarboxylate (10 g, 41.1 mmol in 150 ml
anhydrous diethyl ether) was added slowly to the reaction mixture,
which was then warmed at 35.degree. C. for 3 h. Saturated aqueous
ammonium chloride solution (0.5 ml) was then added. The organic
layer was removed, and the aqueous washed with diethyl ether
(3.times.5 ml). The combined organic layers were dried with brine
and magnesium sulfate before filtering and removal of solvent.
Silica gel chromatography, eluting with 15% ethyl acetate in
hexanes gave the desired pro-duct 6.9 g (70% yield) as a off-white
wax.
[0110] .sup.1H NMR (400 MHz, CDCl.sub.3): 1.4 (9H, m), 2.5 (m, 1H),
2.8 (m, 1H), 3.65 (s, 3H), 4.0 (m, 2H), 4.3-4.5 (m, 1H), 4.9 (m,
2H).
Intermediate 5: 1-tert-butyl 2-methyl
(2S,4EZ)-4-(cyanomethylene)-1,2-pyrrolidine-dicarboxylate
[0111] Diethyl cyanomethyl phosphonate (0.86 ml, 4.4 mmol) was
dissolved in dry THF (50 ml) and the solution cooled to 0.degree.
C. Sodium hydride (205 mg of a 60% suspension in parrafin oil, 5.1
mmol) was then added cautiously and the reaction stirred for 30
min. The reaction mixture was then cooled to -78.degree. C. and a
solution of 1-tert-butyl 2-methyl
(2S)-4-oxo-1,2-pyrrolidinedicarboxylate (1.0 g, 4.1 mmol) in dry
THF (5 ml) was added dropwise. The reaction was then allowed to
reach room temperature. Saturated aqueous ammonium chloride
solution (15 ml) was then added, followed by ethyl acetate (100
ml). (The organic layer was removed, and the aqueous washed with
ethyl acetate (3.times.5 ml). The combined organic layers were
dried with brine and magnesium sulfate before filtering and removal
of solvent. Silica gel chromatography, eluting with 35% ethyl
acetate in hexanes gave the desired compound (860 mg, 80%) as an
off-white wax.
[0112] .sup.1H NMR (360 MHz, CDCl.sub.3): 1.4 (m, 9H), 2. -3.0 (m,
1H), 3.1-3.3 (m, 1H), 3. (m, 3H) 4.2-4.4 (m, 2H), 4.5-4.7 (m, 1H),
5.4 (m, 1H).
Intermediate 6: 1-tert-butyl 2-methyl
(2S,4EZ)-4-benzylidene-1,2-pyrrolidinedicarboxylate
[0113] Potassium tert-butoxide (6.1 g, 54 mmol) was added
portionwise to a solution of benzyl-triphenylphosphonium chloride
(22.45 g, 58 mmol) in anhydrous dichloromethane (400 ml) and the
reaction stirred at ambient temperature for 1 h. The solution was
then cooled to 0.degree. C. and a solution of 1-tert-butyl 2-methyl
(2S)-4-oxo-1,2-pyrrolidinedicarboxylate (9.36 g, 38.5 mmol) in dry
dichloromethane (30 ml) was added dropwise. After stirring for a
further 1 h at 0.degree. C. the reaction was stirred for a further
3 h at ambient temperature. Saturated aqueous ammonium chloride
solution (30 ml) was then added. The organic layer was removed, and
the aqueous washed with dichloromethane (3.times.20 ml). The
combined organic layers were dried with brine and magnesium sulfate
before filtering and removal of solvent. Silica gel chromatography,
eluting with 30% ether in hexanes gave the desired product 8.65 g
(71% yield) as a pale yellow wax.
[0114] .sup.1H NMR (400 MHz, CDCl.sub.3):1.5 (m, 9H), 2.8-3.0 (m,
H), 3.2 (m, 1H), 3.7 (m, 3H), 4.2-4.4 (m, 2H), 4.5-4.6 (m, 1H),
6.3-6.4 (m, H), 7.1-7.5 (m, 5H).
[0115] Intermediate 7:
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidine-carboxyli-
c acid
[0116] A solution was made containing
(2S)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidine-carboxylic acid
(5.0 g, 21 mmol) and O-methylhydroxylamine hydrochloride (2.7 g,
32.8 mmol) in chlorofor (100 ml) containing triethylamine (5.5 g,
55 mmol). The reaction mixture was then stirred at ambient
temperature overnights prior to removal of solvent. The resultant
crude reaction mixture was dissolved in ethyl acetate (150 ml) and
washed rapidly with 1N HCl (40 ml). The acidic layer was then
extracted with ethyl acetate (3.times.20 ml) and the combined
organic layers washed with brine before drying over magnesium
sulfate, filtering and removal of solvent in vacuo. The desired
product (5.3 g, 94%) was isolated as a pale yellow oil.
[0117] .sup.1H NMR (400 MHz. CDCl.sub.3) 1.45 (M, 9H), 2.8-3.2 (m,
2H), 3.9 (s, 3H), 4.2 (m, 2H), 4.5-4.7 (m, 1H).
Intermediate 8:
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(ethoxyimino)-2-pyrrolidinecarboxylic
acid
[0118] A solution was made containing
(2S)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecar-boxylic acid
(5.0 g, 22 mmol) and O-ethylhydroxylamine hydrochloride (6.4 g,
65.5 mmol) in a 1:1 mixture of pyridine and ethanol (100 ml). The
reaction was heated to reflux for 2.5 h before cooling and removal
of solvent. The residue was dissolved in ethyl acetate and washed
rapidly with 1.3N HCl (40 ml). The acidic layer was then extracted
with ethyl acetate (3.times.20 ml) and the combined organic layers
washed with brine before drying over magnesium sulfate, filtering
and removal of solvent in vacuo. The desired product (5.5 g, 93%)
was isolated as a pale yellow oil.
[0119] .sup.1H NMR (400 MHz, DMSO): 1.3 (t, 3H), 1.55 (m, 9H),
2.9-2.7 (m, 1H), 3.4-3.1 (m, 1H), 4.1-4.3 (m, 4H), 4.6 (m, 1H),
12-13.5 (br, 1H).
Intermediate 9:
(2S,4EZ)-4-[(allyloxy)imino]-1-(tert-butoxycarbonyl)-2-pyrrolidinecarboxy-
lic acid
[0120] A solution was made containing
(2)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecar-boxylic acid
(5.0 g, 22 mmol) and O-allylhydroxylamine hydrochloride monohydrate
(7.2 g, 65.5 mmol) in a 1:1 mixture of pyridine and ethanol (100
ml). The reaction was heated to reflux for 2.5 h before cooling and
removal of solvent. The residue was dissolved in ethyl acetate and
washed rapidly with 1.3N HCl (40 ml). The acidic layer was then
extracted with ethyl acetate (3.times.20 ml) and the combined
organic layers washed with brine before drying over magnesium
sulfate, filtering and removal of solvent in vacuo. The desired
product (5.9 g, 94%) was isolated as a pale yellow oil.
[0121] .sup.1H NMR (400 MHz, CDCl.sub.3): 1.5 (m, 9H), 2.8-3.2 (m,
2H), 4.2 (m, 2H), 4.5-4.7 (m, 3H), 5.25 (m, 2H), 5.9 (m, 1H), 11.1
(broad S, 1H).
Intermediate 10: 1-[(aminooxy)methyl]-4-methoxybenzene
[0122] A solution was made of Boc hydroxylamine (2.0 g, 17.1 mmol)
in dry THF (60 ml). Sodium hydride (1.1 g of a 60% suspension in
paraffin oil, 25.7 mmol) was then added and the suspension stirred.
A catalytic amount of KI was then added to the reaction prior to
the cautious addition of 4-methoxybenzyl chloride (3.2 g, 20.4
mmol). The reaction was then allowed to stir overnight before
removal of solvent in vacuo. The residue was taken up with diethyl
ether (100 ml) and HCl gas bubbled in for 20 minutes, causing the
start of precipitation of the product. The flask was stoppered and
left to stand overnight. The product was then filtered off as a
off-white wax (39-52% yield according to varying batches).
[0123] .sup.1H NMR (400 MHz, D.sub.2O):3.8 (s, 3H), 5 (s, 2H), 7.0
(d, 2H), 7.4 (d, 2H).
Intermediate 11:
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-{(4-methoxybenzyl)oxy]imino}-2-pyrroli-
dine-carboxylic acid
[0124] The same method as employed in the preparation of
Intermediate 7, but starting from
(2)-1-(tert-butoxycarbonyl)-4-oxo-2-pyrrolidinecarboxylic acid
(Intermediate 1) and 1-[(aminooxy)methyl]-4-methoxy-benzene
(Intermediate 10) gave the title compound as a gum in a 85%
yield.
[0125] .sup.1H NMR (400 MHz, DMSO): 1.5 (m, 9H), 2.7-2.9 (m, 1H)
3.9 (s, 3H), 4.2 (m, 3H) 4.6 (m, 1H), 5.15 (s, 2H), 7.1 (d, 2H),
7.45 (d, 2H).
Intermediate 12: 2'-methyl[1,1'-biphenyl]-4-carboxylic acid
[0126] To a mixture of 4-bromobenzoic acid (30 g, 0.15 mol),
2-methylphenylboronic acid (24 g, 0.15 mol), sodium carbonate (250
g) in toluene (500 mL) and water (500 mL) was added
tetrakistriphenylphosphine palladium (0) (9 g, 0.0074 mol) under
nitrogen atmosphere. The reaction mixture was refluxed for 10 h.
After this time. 100 ml of 10% NaOH were added to the reaction
mixture, the aqueous layer was separated and washed with toluene
(2.times.200 mL). Acidification of the aqueous layer with 3N HCl
solution gave a solid product, which was filtered, washed with
water and dried. The crude product was then crystallised from
toluene to yield 2'-methyl[1,1'-biphenyl]-4-carboxylic acid (20 g,
62.5%). Conversely, the product could also be obtained from
1-bromo-2-methylbenzene and 4-carboxybenzeneboronic acid, using
analogous conditions.
[0127] .sup.1H NMR (300 MHz, DMSO): 2.2 (s, 3H), 7.2-7.4 (m, 4H),
7.43 (d, J=9Hz, 2H), 7.99 (d, J=9Hz, 2H), 13 (b, 1H).
[0128] Similarly, using the appropriate commercial boronic acids
and arylbromides, the following, related intermediate 1,1'-biphenyl
derivatives (12) were obtained.
4'-methyl[1,1'-biphenyl]-4-carboxylic acid.
2',3-dimethyl[1,1'-biphenyl]-4-carboxylic acid;
2',6'-dimethyl[1,1'-biphenyl]-4-carboxylic acid,
2-methyl[1,1'-biphenyl]-4-carboxylic acid,
3-methyl[1,1'-biphenyl]-4-carboxylic acid
2,2'-dimethyl[1,1'-biphenyl]-4-carboxylic acid;
2'-methoxy-[1,1'-biphenyl]-4-carboxylic acid;
3'-methoxy[1,1'-biphenyl]-4-carboxylic acid;
4'-methoxy[1,1'-biphenyl]-4-carboxylic acid;
2'-chloro[1,1'-biphenyl]-4-carboxylic acid;
3'-chloro[1,1'-biphenyl]-4-carboxylic acid;
4'-chloro[1,1'-biphenyl]-4-carboxylic acid;
3',4'-dichloro[1,1'-biphenyl]-4-carboxylic acid;
2'-(trifluoromethyl)[1,1'-biphenyl]-4-carboxylic acid;
3'-(trifluoromethyl)[1,1'-biphenyl]-4-carboxylic acid;
2'-cyano[1,1'-biphenyl]-4-carboxylic acid;
2',4'-difluoro[1,1'-biphenyl]-4-carboxylic acid;
4-(2-pyridinyl)benzoic acid; 4-(3-pyridinyl)benzoic acid;
4-(4-pyridinyl)benzoic acid; 4-(5-pyrimidinyl)benzoic acid; and
others.
Intermediate 13: 4-(3-methyl-2-pyridinyl)benzoic acid
[0129] A mixture of 2-bromo-3-methylpyridine (22.5 g, 0.1312 mol),
4-(hydroxymethyl)phenylboronic acid (25 g, 0.164 mol),
Pd(PPh.sub.3).sub.4 (9.5 g, 0.0082 mol), and sodium carbonate (200
g in 500 ml of water) in toluene (750 ml) were refluxed under
nitrogen atmosphere for 15 h. Separated the toluene layer and
distilled under reduced pressure to give a residue. The residue was
then purified by column chromatography to yield
[4-(3-methyl-2-pyridinyl)phenyl]methanol (12 g, 47%).
[0130] To a solution of [4-(3-methyl-2-pyridinyl)phenyl]methanol
(12 g, 0.06 mol) in dry DMF (150 mL) was added pyridiniumdichromate
(91 g, 0.24 mol) and stirred at RT for 3 days. The reaction mixture
was poured into water and extracted with ethyl acetate (250 mL).
The organic layer was washed with water, brine, dried and
concentrated. The crude was purified by column chromatography over
silica gel to give 4-(3-methyl-2-pyridinyl)benzoic acid (3 g, 25%)
as white solid.
[0131] .sup.1H NMR (300 MHz, DMSO): 2.3 (s, 3H), 7.33 (dd, J=7.5Hz,
5Hz, 1H), 7.67 (d, J=8Hz, 2H), 7.75 (d, J=7.5Hz, 1H), 8.01 (d,
J=8Hz, 2H), 8.50 (d, J=5Hz, 1H), 13 (b, 1H).
Intermediate 14: 4-(1-oxido-3-pyridinyl)benzoic acid
[0132] To a mixture of 4-tolylboronic acid (38 g, 0.28 mol),
3-bromopyridine (44 g, 0.28 mol), Na.sub.2CO.sub.3 (200 g) in
toluene (500 ml) and water (500 ml) was added Pd(PPh.sub.3).sub.4
(16 g, 0.014 mol), and refluxed for 16 h. The reaction mixture was
cooled, and the separated organic layer was washed with water and
brine, and dried. The solvent was removed to give
4-(3-pyridyl)toluene (42 g, 90%).
[0133] To a mixture of 4-(3-pyridyl)toluene (35 g, 0.207 mol) in
pyridine (400 ml) and water (400 ml) was added KMnO.sub.4 (163 g,
1.03 mol) in portions and refluxed for 12 h. The reaction mixture
was filtered through celite and acidified with conc. HCl. The
product was washed with water and dried to give
4-(3-pyridyl)benzoic acid (32 g, 76%) as a white solid. To a
mixture of 4-(3-pyridyl)benzoic acid (22 g, 0.11 mol) in THF
(2.51), mCPBA (152 g, 0.44 mol, 50%) was added and stirred at RT
for 12 h. The solid was filtered, and washed with THF to give
4-(1-oxido-3-pyridinyl)benzoic acid (20 g, 86%).
[0134] .sup.1H NMR (300 MHz, DMSO): 7.5-7.8 (m, 5H), 7.9 (d, J=8Hz,
2H), 8.33 (d, J=5Hz, 2H).
[0135] Similarly, starting from 4-tolylboronic acid (45 g, 0.33
mol) and 2-bromopyridine (52 g, 0.33 mol), the related inter ediate
4-(1-oxido-2-pyridinyl)bemzoic acid was obtained.
Example 1
General Procedure for the Saponification of Methylesters of
Oximether and/or Olefin-type 2-pyrrolidinecarboxylic Acid
Intermediates (Schemes 3, 7)
[0136] A solution of sodium hydroxide (73 mg, 1.81 mmol) in water
(1.2 ml) was added to a proline oximether methyl ester derivative,
e.g. methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate (391 mg, 1.1 mmol) in 3:1 dioxane:water (12
ml) and the reaction stirred for 3 h. The reaction mixture was then
washed with diethyl ether (2.times.10 ml), and the aqueous phase
acidified to pH 2 (0.1N HCl) and extracted into ethyl acetate. The
ethyl acetate layer was then dried over magnesium sulfate, filtered
and the solvent was then removed in vacuo to give the desired
product, e.g.
(2S4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidine-carboxylic acid in 91% yield as an oil which was used
without further purification.
[0137] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.25 (m, 3H, ArCH.sub.3),
2.96-3.35 (m, 2H), 3.84 (m, 3H), 437 (br s, 2H) 5.17 (m, 1H)
7.14-7.32 (m, 4H, H arom.), 7.34-7.44 (m, 2H, H arom.), 7.53-7.63
(m, 2H, H arom.) M.sup.+ (APCI.sup.+): 353: M.sup.-(APC.sup.-):
351.1.
Example 2
General Protocols for the Esterification of Oximeter- and/or
Olefin-type 2-pyrrolidinecarboxylic Acid Intermediates (Schemes 2,
5, 7):
a) Methylesters (e.g. 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidine-dicarboxylate):
[0138] A solution of the oximether- and/or olefin-type
2-pyrrolidinecarboxylic acid intermediate, e.g.
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarboxylic
acid (0.648 g, 2.5 mmol), in a 1:1 mixture of methanol and toluene
(35 ml) was made. Trimethylsilyl diazomethane (3.8 ml of a 2M
solution in hexanes, 7.5 mmol) was then added dropwise to the
stirred solution at room temperature under nitrogen. After
completion of the evolution of nitrogen gas, the resulting yellow
solution was evaporated in vacuo, and the residue filtered through
a pad of silica gel, eluting with ethyl acetate. Removal of solvent
from the filtrate gave the methylester product, e.g. 1-tert-butyl
2-methyl (2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate, as
a yellow oil (0.646 g, 95% yield).
b) Other esters (e.g. sec-butyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate):
[0139] A solution was made containing the the oximether- and/or
olefin-type 2-pyrrolidinecarboxylic acid inter ediate, e.g.
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylic acid (50 mg, 0.14 mmol), an alcohol, e.g.
isobutanol (0.012 ml, 0.128 mmol) and DMAP (6 mg, 0.05 mmol) in
anhydrous DCM (5 ml). At 0.degree. C., EDC (27 mg, 0.14 mmol) in
DCM (2.5 mL) was added dropwise. The reaction mixture was stirred 2
h at 0.degree. C. followed by 4 h at r.t. The reaction mixture was
concentrated in vacuo and the residue was redissolved in EtOAc. The
resulting solution was washed with HCl 0.1N, water, NaHCO.sub.3 sat
and brine and dried over magnesium sulfate. After filtration
through a pad of silica and evaporation of the solvents, the
desired product, e.g. (2S,4EZ)-4-(methoxyimino)
1-(2'-methyl[1,1'-biphenyl'-4-yl)carbonyl]-2-pyrrolidinecarboxylic
acid was isolated as a mixture of two isomers as an oil in 69%
yield (96.2 % purity by HPLC).
[0140] .sup.1H NMR (300 MHz, CDCl.sub.3): 0.7-1.0 (m, 3H),
1.02-1.34 (m, 3H), 1.38-1.72 (m, 2H), 2.24 (m, 3H, ArCH.sub.3),
2.75-3.18 (m, 2H), 3.84 (m, 3H, NOCH.sub.3), 4.12-4.48 (m, 2H),
4.54-5.18 (m, 2H), 7.13-7.29 (m, 4H), 7.31-7.62 (m, 4H).
M.sup.+(APCI.sup.+) 409.
Example 3
Cyclopentyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate
[0141] Following the general methods as outlined in Example 2,
starting from
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl-
]-2-pyrrolidinecarboxylic acid and cyclopentanol, the title
compound was isolated, after flash-chromatography, as a mixture of
two isomers as an oil in 57% yield (95.6% purity by HPLC).
[0142] .sup.1H NMR (300 MHz, CDCl.sub.3): 1.47-1.98 (m, 8H), 2.24
(m, 3H, ArCH.sub.3), 2.73-3.14 (m, 2H), 3.84 (m, 3H, NOCH.sub.3),
4.11-4.46 (m, 2H), 4.61 (br s, 1H), 4.99-5.32 (m, 2H), 7.15-7.28
(m, 4H), 7.31-7.41 (m, 2H), 7.51-7.62 (m, 2H). M.sup.+(APCI.sup.+):
421.
Example 4
[0143] General Protocol for the Solution-Phase Synthesis of
Oximether Pyrrolidine Derivatives of General Formula (I) (Scheme
1); e.g., methyl
(2S,4EZ)-4-(methoximino-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-pyr-
olidinecarboxlate; methyl
(2S,4E)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate;
methyl(2S,4Z)-4-(methoximino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-
-2-pyrrolidinecarboxylate;
methyl(2S,4EZ)-4-(methoxyimino)-1-[2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl-
]-2-pyrrolidinecarboxylate
a) Protocol for the N-deprotection Step
[0144] Method A: A solution was made containing e.g. 1-tert-Butyl
2-methyl (2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate
(0.892 g, 3.28 mmol), in anhydrous DCM (28 ml). TFA (20%, 7 mL) was
added dropwise. The mixture was stirred at r.t. for 20 min.
Solvents were evaporated and the desired product, e.g. methyl
(2S,4EZ)-4-(methoxyimino)-2-pyrrolidinecarboxylate (0.564 g,
quant.) was isolated as a yellow oil and used without further
purification.
[0145] Method B: A solution was made containing e.g. 1-tert-Butyl
2-methyl (2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate (60
mg, 0.22 mmol), in anhydrous DCM (6 ml). At 0.degree. C., HCl gas
was bubbled slowly through the reaction and the deprotection was
followed by TLC. After approximately 30 minutes, the DCM was
evaporated. The product was concentrated in vacuo from DCM (2-3
times) to remove the HCl. The desired product, e.g. methyl
(2S,4EZ)-4-(methoxyimino)-2-pyrrolidinecarboxylate (38 mg, quant.)
was isolated as a yellow solid and used without further
purification.
b) Protocol for the N-capping Step
[0146] Method A (e.g. methyl
(2S,4EZ)-4-(methoxyimino)-1-[2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate: A solution of
methyl-(2S,4EZ)-4-(methoxyimino)-2-pyrrolidinecarboxylate (0.564 g,
3.28 mmol), 2'-methyl[1,1'-biphenyl]-4-carboxylic acid (0.765 g,
3.60 mmol) and 4-dimethylaminopyridine (0.880 g, 7.21 mmol) in a
7:3 mixture of DCM and DMF (30 ml) was made. EDC (0.691 mg, 3.60
mmol) was added slowly at 0.degree. C.
[0147] The reaction mixture was stirred overnight at r.t. It was
washed with water (twice 20 ml), dried over MgSO.sub.4, filtrated
and evaporated in vacuo. The resulting crude product mixture,
methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate, was purified by flash chromatography, using
cyclohexane/EtOAc 8:2 as eluent. After several further
chromatographies, (E)- and (Z)-isomers could be separated: methyl
(2S,4E)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate (261 mg, 22%) was isolated as a colorless
powder in 98.3% purity by HPLC, and methyl
(2S,4E)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate (237 mg, 20%) was isolated as a colorless
powder in 98.3% purity by HPLC.
[0148] Methyl
(2S,4E)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate: M.p. 38.degree. C.; IR (neat) .nu. 2952,
1743, 1640, 1405, 1206, 1177, 1045, 851 cm.sup.-1; .sup.1H NMR (300
MHz, CDCl.sub.3): 2.27 (s, 3H, ArCH.sub.3), 2.92-3.18 (m, 2H), 3.81
(m, 3H), 3.87 (m, 3H), 4.37 (m, 2H), 5.20 (m, 1H), 7.16-7.32 (m,
4H, H arom.), 7.35-7.42 (m, 2H, H arom.), 7.55-7.67 (m, 2H, H
arom.). M.sup.+(APCI.sup.+): 367.3. Analysis calculated for
C.sub.28H.sub.29N.sub.3O.sub.4 0.1 H.sub.2O: C, 68.50; H, 6.08; N.
7.61. Found: C, 68.23; H, 6.16; N, 7.45.
[0149] Methyl
(2S,4Z)-4-(methoxyimino)-1-[(2'-methyl[1,1'-biphenyl]-4-yl)carbonyl]-2-py-
rrolidinecarboxylate: M.p 40.degree. C.; IR (neat) .nu. 2937, 1742,
1640, 1405, 1207, 1177, 1045, 754 cm.sup.-1; .sup.1H NMR (300 MHz,
CDCl.sub.3): 2.27 (s, 3H, ArCH.sub.3), 2.92-3.18 (m, 2H), 3.81 (m,
3H), 3.87 (m, 3H), 4.37 (m, 2H), 5.20 (m, 1H), 7.16-7.32 (m, 4H, H
arom ), 7.35-7.42 (m, 2H, H arom.), 7.55-7.67 (m, 2H, H arom.).
M.sup.+(APCI.sup.+): 367.3 Analysis calculated for
C.sub.28H.sub.29N.sub.3O.sub.4: C, 68.84; H, 6.05; N. 7.65. Found:
C, 68.46; H, 6.26; N, 7.35.
[0150] Method B (e.g. methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate): To a solution of
2'-fluoro[1,1'-biphenyl]-4-carboxylic acid (69 mg, 0.32 mmol.) in 9
ml THF, were added oxalyl chloride (0.09 mL, 0.99 mmol) and DMF
(three drops) under ice cooling. The mixture was stirred for 2h at
rt. The solvent was removed affording the corresponding acyl
chloride, 2'-fluoro[1,1'-biphenyl]-4-carbonyl chloride. The latter
was now dissolved in THE (7 mL) and added slowly on a 0.degree. C.
solution containing the free NH-compound from the previous step,
e.g. methyl (2S,4EZ)-4-(methoxyimino)-2-pyrrolidinecarboxylate (38
mg, 0.22 mmol), and triethylamine (2 eq, 0.44 mmol, 0.06 ml) in
THF/DCM 1:1 mixture (12 ml). The reaction mixture was stirred
overnight at r.t. Pol-trisamine was added (69 mg, 3.45 mmol/g) in
order to scavenge excess of acyl chloride. The mixture was shaken 5
h, filtered and the resulting solution was washed with NH.sub.4Cl
20%, brine, and dried over MgSO.sub.4. After filtration and
evaporation of the solvents, the resulting dark oil (3.26 g) was
purified by SPE (SAX sorbent) using neat DCM as eluent. The desired
product, e.g. methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate was obtained as a mixture of two isomers as a
white foam in 34% yield (97.3% purity by HPLC).
[0151] Methyl
(2S,4EZ)-4-(methoxyimino)-1-[(2'-fluoro[1,1'-biphenyl]-4-yl)carbonyl]-2-p-
yrrolidinecarboxylate: .sup.1H NMR (300 MHz, CDC.sub.3): 2.80-3.20
(m, 2H), 3.70-385 (m, 6H), 4.07-4.40 (m, 2H), 3.55-3.82 (m, 1H),
3.90-4.44 (m, 2H), 5.20 (m, 1H), 7.13-7.25 (m, 2H), 7.30-7.46 (m,
2H), 7.61 (m, 4H). M.sup.+(APCI.sup.+): 371.2
c) E/Z-Isomerisation
[0152] The pure E-isomer was isomerized to a mixture of the
E/Z-isomers by the following procedure: the E-isomer was dissolved
in dioxane/water 3:1 mixture. NaOH (1.7 eq; 0.52 mL of NaOH 1.6N)
was added and the resulting solution was stirred 2 h at r.t. The
mixture was neutralysed with HCl 0.1 N and lyophilised. The
components of the resulting E/Z-mixture were separated and purified
by flash chromatography using same conditions as described
above.
Example 5
Methyl (2S,4EZ)-1-[(4'-fluoro
[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxy-imino)-2-pyrrolidinecarboxylate
[0153] Following the general methods as outlined in Example 4,
starting 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate and
4-fluoro[1,1'-biphenyl]-4-carboxylic acid, the title compound was
isolated, after flash-chromatography, as a mixture of two isomers
as an oil in 39% yield (97.6% purity by HPLC).
[0154] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.72-3.20 (m, 2H),
3.74-3.87 (m, 6H), 4.10-4.42 (m, 2H), 5.20 (m, 1H), 7.12-7.18 (m,
2H), 7.53-7.61 (m, 6H). M.sup.+(APCI.sup.+): 371.2
Example 6
Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(5-pyrimidinyl)benzoyl]-2-pyrlidin-
ecarboxylate
[0155] Following the general methods as outlined in Example 4,
starting from 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate and
4-(5-pyrimi-dinyl)benzoic acid, the title compound was obtained,
after flash-chromatography, as a mixture of two isomers as an oil
in 68% yield (93.0% purity by HPLC).
[0156] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.64-3.20 (m, 2H),
3.74-3.87 (m, 6H), 4.16-4.64 (m, 2H), 5.18 (m, 1 H), 7.64-7.73 (m,
4H), 8.97 (d, 2H), 9.26 (s, 1H). M.sup.+(APCI.sup.+): 355.3.
Example 7
Methyl
(2S,4EZ)-1-([1,1'-biphenyl]-4-ylcarbonyl)-4-(methoxyimino)-2-pyrr-
olidinecarboxylate
[0157] Following the general methods as outlined in Example 4,
starting from 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate and
[1,1'-biphenyl]-4-carbonyl chloride, the title compound was
isolated, after flash-chromatography, as a mixture of two isomers
as an oil in 31% yield (99% purity by HPLC).
[0158] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.88 (m, 1H), 3.07 (m,
1H), 3.80 (m, 6H), 4.20-4.45 (m, 2H), 4.65 (br s, 1H), 5.15 (m,
1H), 7.33-7.49 (m, 4H), 7.54-7.69 (m, 5H). M.sup.+(APCI.sup.+):
353.2.
Example 8
Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(2-pyridinyl)benzoyl]-2-pyrrolidin-
ecarboxylate
[0159] Following the general method as outlined in Example 4
(Method B), starting from 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate and
4-(2-pyridinyl)benzoic acid, the title compound was obtained, after
flash-chromatography (eluent cyclohexane/ethyl acetate 8:2), as a
mixture of two isomers in 45% yield (95% purity by HPLC).
[0160] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.90-3.20 (m, 2H),
3.70-3.85 (m, 6H), 4.26-4.35 (m, 2H), 5.15 (m, 1H), 7.26 (m, 2H),
7.30-7.76 (m, 4H), 8.10 (m, 2H), 8.73 (m, 1H). M.sup.+(ESI.sup.+):
354.
Example 9
Methyl
(2S,4EZ)-4-(methoxyimino)-1-[4-(3-methyl-2-pyridinyl)benzoyl]-2-p-
yrrolidinecarboxylate
[0161] Following the general method as outlined in Example 4
(Method B), starting from 1-tert-butyl 2-methyl
(2S,4EZ)-4-(methoxyimino)-1,2-pyrrolidinedicarboxylate and
4-(3-methyl-2-pyridinyl)benzoic acid, the title compound was
obtained, after flash-chromatography (eluent cyclohexane/ethyl
acetate 8:2), as a mixture of two isomers in 50% yield (100% purity
by HPLC).
[0162] .sup.1H NMR (300 MHz, CDCl.sub.3); 2.38 (s, 3H), 2.80-3.20
(m, 2H), 3.70-3.85 (m, 6H), 4.21-4.41 (m, 2H), 5.16 (m, 1H), 7.64
(m, 6H), 8.55 (m, 1H). M.sup.+(APCI.sup.+): 368.2.
Example 10
General Protocol for the Solution-Phase Synthesis of Oxime or
Hydrazone Pyrrolidine Derivatives of General Formula (I) (Scheme
6)
a) Protocol for the Hydrolysis of the Oximether Group.
[0163] The starting oximether compounds, (0.14 mmol),
paraformaldehyde powder (95%, 1.41 mmol) and Amberlyst 15 (30 mg)
were mixed in acetone containing 10% of water (2 mL). The reaction
was stirred 4 h at 60.degree. C. Insoluble materials were filtered
off and washed with a small amount of acetone. The filtrate was
concentrated and the residue was diluted with DCM (15 mL). The
organic solution was washed with brine (10 mL), dried over
Na2SO.sub.4, and concentrated. The desired 4-ketopyrroldidine
product was isolated as a yellow oil and used without further
purification (92%).
b) Protocol for the Formation of Oxime and/or Hydrazone
Compounds
[0164] A solution was made containing the ketopyrrolidine
derivative from the previous step (0.11 mmol) and hydroxylamine
hydrochloride (0.17 mmol) in chloroform (1 ml) containing
triethylamine (0.29 mmol), or hydrazine hydrate (4% in EtOH). The
reaction mixtures were then stirred at ambient temperature for one
day, prior to removal of solvent. The resultant crude reaction
mixtures were purified by column chromatography using DCM/NeOH
(25:1) to collect the desired oxime or hydrazone products,
respectively.
Example 11
General Protocol for the Solid-Phase Synthesis of Pyrrolidine Ester
Derivatives of General Formula (I) (Scheme 8)
a) Loading Step
[0165] Kaiser oxime resin (16.5 g, loading 1.57 mmol/g) was added
to a solution of the relevant pyrrolidine carboxylic acid building
block (51.8 mmol) ad diisopropylcarbodiimide (8.1 ml, 51.8 mmol) in
dry dichloromethane (150 ml). The resulting suspension was shaken
over-night before filtering at the pump and washing sequentially
with DMF, DCM and finally diethyl ether before drying at room
temperature in vacuo.
b) N-Deprotection Step
[0166] The resin obtained in the loading step was shaken with a 20%
solution of trifluoroacetic acid in dichloromethane (200 ml) for 30
minutes prior to filtering at the pump and washing sequentially
with aliquots of DMF, DCM and finally diethyl ether before drying
at room temperature in vacuo
c) N-Capping Step
[0167] The resin from the previous step was transferred into a
96-well filter-plate (approx. 50 mg of dry resin/well) and each
well treated with an N-reactive derivatising agent, e.g. with
either of the following solutions: [0168] a) an acid chloride
(0.165 mmol) and diisopropylethylamine (0.165 mmol) in dry
dichloromethane (1 ml), overnight [0169] b) an acid (0.165 mmol)
and DIC (0.165 mmol) in, depending on the solubility of the
carboxylic acid, dry dichloromethane or MP (1 ml) overnight. The
tubes were closed with a stopper and shaken overnight at ambient
temperature. The resins were then filtered, washing the resin
sequentially with aliquots of DMF, DCM and finally diethyl ether
before drying at room temperature in vacuo. d) Cleavage Step
[0170] A solution of MeOH (20 eq, 50 .mu.L) and TEA (1 eq 8 .mu.L)
in DCM (1.45 mL) was added to each tube containing the resin from
the previous step. They were shaken for 2 days at room temperature.
They were then filtered into individual vials and the solvent
removed in a vacuum centrifuge to yield about 10 mg of the
corresponding products (between 40 and 50% yield). The products
were characterised by LC (MaxPlot detection between 230 and 400 nm)
and mass spectrometry (ES+). All of the following examples were
identified based on the observation of the correct molecular ion n
the mass spectrum and were shown to be at least 40% pure (usually
60-95% pure) by LC.
Example 12
Ethyl
(2S,4EZ)-1-([1,1'-biphenyl]-4-ylcarbonyl)-4-(methoxyimino)-2-pyrro-
lidinecarboxylate
[0171] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tertbutoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbox-
ylic acid, [1,1'-biphenyl]-4-carbonyl chloride, and ethanol, the
title compound was isolated as a mixture of two isomers in 87.2%
purity by HPLC.
[0172] .sup.1H NMR (300 MHz, CDCl.sub.3): 1.43 (m, 3H), 2.76-3.18
(m, 2H), 3.74-3.94 (m, 5H), 4.09-4.48 (m, 2H), 5.14 (m, 1H),
7.32-7.51 (m, 4H), 7.52-7.70 (m, 5H). M.sup.+(APCI.sup.+): 367.
Example 13
Methyl
(2S,4EZ)-1-[(2'-chloro[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyim-
ino)-2-pyrrolidinecarboxylate
[0173] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 2'-chloro[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound isolated as a mixture of two isomers
in 92.3% purity by HPLC.
[0174] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.85 (m, 1H), 3.05 (m,
1H), 3.72-3.94 (m, 6H), 4.27 (m, 1H), 4.41 (m, 1H), 4.68 (br s,
1H), 5.15 (m, 1H), 7.23-7.35 (m, 3H), 7.42-7.53 (m, 3H), 7.55-7.64
(m, 2H). M.sup.+(APCI.sup.+): 387.
Example 14
Methyl
(2S,4EZ)-1-[(2'-cyano[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimi-
no)-2-pyrrolidinecarboxylate
[0175] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 2'-cyano[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound was isolated as a mixture of two
isomers in 91.6% purity by HPLC.
[0176] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.75-3.18 (m, 2H),
3.72-3.94 (m, 6H), 4.25 (m, 1H), 4.41 (m, 1H), 4.62 (br s, 1H),
5.15 (m, 1H), 7.40-7.55 (m, 3H), 7.56-7.71 (m, 4H), 7.77 (m, 1H).
M.sup.+(APCI.sup.+): 378.
Example 15
Methyl
(2S,4EZ)-4-(methoxyimino)-1-{[2'-(trifluoromethyl)[1,1'-biphenyl]-
-4-yl]carbonyl}-2-pyrrolidinecarboxylate
[0177] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 2'-(trifluoromethyl)[1,1'-biphenyl]-4-carboxylic acid,
and methanol, the title compound was isolated as a mixture of two
isomers in 86.3% purity by HPLC.
[0178] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.85 (m, 1H), 3.06 (m,
1H), 3.72-3.94 (m, 6H), 4.26 (m, 1H), 4.41 (m, 1H), 4.62 (br s,
1H), 5.17 (m, 1H), 7.29 (m, 1H), 7.37 (m, 2H), 7.48 (m, 1H), 7.56
(m, 3H), 7.74 (m, 1H). M.sup.+(APCI.sup.+): 421.
Example 16
Methyl
(2S,4EZ)-1-[(2'-methoxy[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyi-
mino)-2-pyrrolidinecarboxylate
[0179] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 2'-methoxy[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound was isolated as a mixture of two
isomers in 92.1% purity by HPLC.
[0180] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.85 (m, 1H), 3.06 (m,
1H), 3.67-3.94 (m, 9H), 4.23-4.49 (m, 1H), 5.14 (m, 1H), 6.94-7.07
(m, 2H), 7.26-7.67 (m, 6H). M.sup.+(APCI.sup.+): 383.
Example 17
Methyl
(2S,4EZ)-1-[(2',6'-dimethyl[1,1'-biphenyl]-4-yl)carbonyl]-4-(meth-
oxyimino)-2-pyrrolidinecarboxylate
[0181] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 2',6'-dimethyl[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound was isolated as a mixture of two
isomers in 88.3% purity by HPLC.
[0182] .sup.1H NMR (300 MHz, CDCl.sub.3): 1.98 (s, 3H), 2.00 (s,
3H), 2.67-3.18 (m, 2H), 3.65-3.94 (m, 6H), 4.12-4.75 (m, 3H), 5.15
(m, 1H), 7.05-7.27 (m, 5H), 7.35-7.67 (m, 2H). M.sup.+(APCI.sup.+):
381.
Example 18
Methyl
(2S,4EZ)-1-[(2',3-dimethyl[1,1'-biphenyl]-4-yl)carbonyl]-4-(metho-
xyimino)-2-pyrrolidinecarboxylate
[0183] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinearbox-
ylic acid, 2',3-dimethyl[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound was isolated as a mixture of two
isomers in 81.4% purity by HPLC.
[0184] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.20-2.45 (m, 6H),
272-3.20 (m, 2H), 3.65-3.94 (m, 6H), 3.96-4.24 (m, 2H), 5.11 (m,
1H), 7.10-7.29 (m 7H). M.sup.+(APCI.sup.+): 381.
Example 19
Methyl (2S,4EZ)-1-[(3-methyl
[1,1'-biphenyl]-4-yl)carbonyl]-4-(methoxyimino)-2-pyrrolidinecarboxylate
[0185] Following the general method as outlined in Example 11,
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 3-methyl [1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound isolated as a mixture of two isomers
in 82.3% purity by HPLC.
[0186] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.40 (m, 3H, ArCH3),
2.65-3.20 (m, 2H), 3.74-3.87 (m, 6H), 3.92-4.20 (m, 2H), 5.10 (m,
1H), 7.16-7.48 (m, 2H), 7.56 (m, 2H). M.sup.+(APCI.sup.+): 367.
Example 20
Methyl
(2S,4EZ)-1-[(3',4'-dichloro[1,1'-biphenyl]-4-yl)carbonyl]-4-(meth-
oxyimino)-2-pyrrolidinecarboxylate
[0187] Following the general method as outlined in Example 11
starting from
(2S,4EZ)-1-(tert-butoxycarbonyl)-4-(methoxyimino)-2-pyrrolidinecarbo-
xylic acid, 3',4'-dichloro[1,1'-biphenyl]-4-carboxylic acid, and
methanol, the title compound was isolated as a mixture of two
isomers in 91.9% purity by HPLC.
[0188] .sup.1H NMR (300 MHz, CDCl.sub.3): 2.72-3.18 (m, 2H),
3.65-3.94 (m, 6H), 4.21 (m, 1H), 4.37 (m, 1H), 5.15 (m, 1H),
7.35-7.69 (m, 7H). M.sup.+(APCI.sup.+): 421.
Example 21
Preparation of a Pharmaceutical Formulation
[0189] The following formulation examples illustrate representative
pharmaceutical compositions according to the present invention,
being not restricted thereto.
Formulation 1--Tablets
[0190] A pyrrolidine compound of formula (I) is admixed as a dry
powder with a dry gelatin binder in an approximate 1:2 weight
ration. A minor amount of magnesium stearate is added as a
lubricant. The mixture is formed into 240-270 mg tablets (80-90 mg
of active pyrrolidine compound per tablet) in a tablet press.
Formulation 2--Capsules
[0191] A pyrrolidine compound of formula (I) is admixed as a dry
powder with a starch diluent in an approximate 1:1 weight ratio.
The mixture is filled into 250 mg capsules (125 mg of active
pyrrolidine compound per capsule).
Formulation 3--Liquid
[0192] A pyrrolidine compound of formula (I) (1250 mg), sucrose
(1.75 g) and xanthan gum (4 mg) are blended, passed through a No.
10 mesh U.S. sieve, and then mixed with a previously prepared
solution of microcrystalline cellulose and sodium carboxy ethyl
cellulose (11:89, 50 mg) in water. Sodium benzoate (10 mg), flavor,
and color are diluted with water and added with stirring.
Sufficient water is then added to produce a total volume of 5
mL.
Formulation 4--Tablets
[0193] A pyrrolidine compound of formula (I) is admixed as a dry
powder with a dry gelatin binder in an approximate 1:2 weight
ratio. A minor amount of magnesium stearate is added as a
lubricant. The mixture is formed into 450-900 mg tablets (150-300
mg of active pyrrolidine compound) in a tablet press.
Formulation 5--Injection
[0194] A pyrrolidine compound of formula (I) is dissolved in a
buffered sterile saline injectable aqueous medium to a
concentration of approximately 5 mg/ml.
Example 22
Biological Assays
[0195] The compounds according to formula (I) may be subjected to
the following assays:
a) In vitro competition binding assay on hOT receptor with
Scintillation Proximity Assay (see Cook, N. D. et al.
Pharmaceutical Manufacturing International 1992. p. 49-53)
[0196] This assay allows to deter mine the affinity of the test
compounds for the human Oxytocin (hOT) receptor. Membranes from
HEK293EBNA (cells expressing the hOT receptor) were suspended in
buffer containing 50 mM Tris-HCl, pH 7.4, 5 mM MgCl2 and 0.1% BSA
(w/v). The membranes (2-4 .mu.g) were mixed with 0.1 mg SPA bead
coated with wheat-germ, aglutinin (WGA-PVT-Polyethylene Imine beads
from Amersham) and 0.2 nM of the radiolabelled [.sup.125I]-OVTA
(OVTA being Ornithin Vasoactive, an analogue of OT for competitive
binding experiments). Non-specific binding was determined in the
presence of 1 .mu.M Oxytocin. The total assay volume was 100 .mu.l.
The plates (Corning.RTM. NBS plate) were incubated at room
temperature for 30 min and counted on a Mibrobeta.RTM. plate
scintillation counter. Competitive binding was performed in
presence of compounds of formula (I) at the following
concentrations: 30 .mu.M, 10 .mu.M, 1 .mu.M, 300 nM, 100 nM, 10 nM,
1 nM, 100 pM, 10 pM. The competitive binding data were analysed
using the iterative, nonlinear, curve-fitting program, "Prism"
(GrapPad Software, Inc).
[0197] The ability of the pyrrolidine derivatives of formula (I) to
inhibit the binding of .sup.125I-OVTA to the OT-receptor was
assessed using the above described in vitro biological assay.
Representative values for some example compounds are given in Table
1, where the binding affinity of the compounds is expressed by the
IC.sub.50 (.mu.M) which is the concentration upon which 50%
inhibition of OT-R is achieved. From these values, it can be
derived that said test compounds according to formula (I) do show a
significant binding to the oxytocin receptor.
[0198] According to a preferred embodiment, the compounds of the
invention display binding affinities (K.sub.i (.mu.M)) of less 0.40
.mu.M, more preferred of less than 0.1 .mu.M. TABLE-US-00001 TABLE
1 Binding affinity human OT-R Structure IUPAC-Name IC.sub.50
(.mu.M) ##STR13## Methyl (2S,4EZ)-1-([1,1'-biphenyl]-4-
ylcarbonyl)-4-(methoxyimino)-2- pyrrolidinecarboxylate 0.045
##STR14## Methyl (2S,4EZ)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.028 ##STR15## Methyl (2S,4E)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.036 ##STR16## Methyl (2S,4E)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.012 ##STR17## Methyl (2S,4EZ)-4-(methoxyimino)-1-[(2'-
fluoro[1,1'biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.10
b) Functional Assay No. 1: Inhibition of Oxytocin Mediated
Ca.sup.2+-Mobilization by FLIPR.RTM. (Fluorimetric Imaging Plate
Reader)
[0199] The action of OT on the OT-receptor triggers a complex
cascade of events in the cell which leads to an increase in the
intra-c toplasmic Ca.sup.2+ concentration. This increase in
Ca.sup.2+ concentration results from both calcium release from the
sarcoplasmic reticulum (calcium stores) into the cytoplasm and from
calcium influx from the extracellular space through Ca.sup.2+
channels. This Ca.sup.2+ mobilization into the cytoplasm triggers
the contractile machinery of the myometrial cells which leads to
uterine contractions (see Gimpl C. and Fahrenholz, F. Physiological
Reviews 2001, 81, 629-683 as well as Mitchell, B. F. and Schmid, B.
J. Soc. Gynecol. Invest. 2001, 81, 122-33).
[0200] This assay allows the measurement of the inhibition of
OT/OT-R mediated calcium mobilization by test compounds of formula
(I).
[0201] FLIPR.RTM. is a fluorimetric imaging device using a laser
(Argon-ion laser) for simultaneous illumination and reading (cooled
CCD camera) of each well of a 96-well-plate, thus enabling rapid
measurements on a large number of samples.
[0202] Preparing the plates: FLIPR-plates were precoated with PLL
(Poly-L-Lysine) 10 .mu.g/ml+0.1% gelatins to attach HEK293EBNA
cells (Human Embryonic Kidney cells expressing the hOT receptor)
and incubated for 30 min up to 2 days at 37.degree. C. The cells
were plated out into 96-well-plates (60000 cells/well).
[0203] Labeling of fluo-4: 50 .mu.g of fluo-4 (Ca2+ sensitive
fluorescent dye) were dissolved in 20 .mu.l pluronic acid (20% in
DMSO). The dissolved fluo-4 was then diluted in 10 ml DMEM
(Dubecco's Minimal Essential Medium)-F12 culture medium. The plates
were washed one time with DMEM-F12 medium 100 .mu.l of the fluo-4
containing-DMEM-F12 medium were added to the HEK-cells which were
incubated for 1.5-2h in this fluorescent medium, Fluo-4 is taken up
by the cytoplasm of the cells.
[0204] Buffer: 145 mM NaCl, 5 mM KCl, 1 mM MgCl.sub.2, 10 mM Hepes,
10 mM Glucose, EGTA (Ethylene-bis oxyethylene nitrilo tetraacetic
acid). The pH was adjusted to 7.4.
[0205] Performance of the assay: A minimum of 80 .mu.l/well of
compounds of formula (I) (5.times.) in the above buffer (1.times.)
were prepared (96-well-plates). The compounds of formula (I) were
added to the 96-well-plates at different concentrations (30 .mu.M,
10 .mu.M, 1 .mu.M, 300 nM, 100 n, 10 nM, 1 nM, 100 pM, 10 pM). OT
was added at a concentration of 40 nM.
[0206] The relative fluorescence of Fluo-4 (.lamda..sub.ex=488 nm,
.lamda..sub.em=590 nm) is then measured by the FLIPR in presence or
absence of compounds of formula (I). The fluorescence of the marker
being sensitive to the amount of Ca.sup.2+, the Ca.sup.2+ movements
can be detected. Then, the ability of compounds of formula (I) to
antagonize the oxytocin-induced intracellular
Ca.sup.2+-mobilization mediated by the oxytocin receptor may be
determined.
[0207] The activities of the pyrrolidine derivatives according to
formula (I) were assessed using the above described in vitro
biological assay. Representative values for some example compounds
are given in Table 2. The values refer to the concentration of the
test compounds according to formula (I) necessary to antagonize by
50% the OT/OTR intracellular Ca.sup.2+-mobilization. From the
values, it can be derived that said example compounds according to
formula (I) do exhibit a significant activity as oxytocin receptor
antagonists. TABLE-US-00002 TABLE 2 Inhibition of Ca.sup.2+-
mobilization, hOT-R Structure IUPAC-Name IC.sub.50 (.mu.M)
##STR18## Methyl (2S,4E)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.015 ##STR19## Methyl (2S,4Z)-4-(methoxyimino)-1-[(2'-
methyl[1,1'biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.015
c) Functional Assay No. 2: Inhibition of IP3 (Inositol
Tri-Phosphate)-Synthesis in HEK/EBNA-OTR Cells
[0208] The interaction of OT on the OT-receptor leads to the IP3
synthesis, IP3 being a second messenger for the Ca.sup.2+ release
from sarcoplasmic reticulum, involved in the uterine contraction
triggering process (see Mitchell, B. F. and Schmid B. J. Soc.
Gynecol. Invest. 2001, 8, 122-33).
[0209] This assay can be used to show the inhibition of the OT/OT-R
mediated IP3 synthesis by using test compounds of formula (I).
[0210] Stimulator of the cells: HEK/EBNA OTR (rat or human) cells
are plated out into costar 12-well plates, and equilibrated for
15-24 h with 4 .mu.Ci/ml radiolabelled [.sup.3H]-Inositol with 1%
FCS (0.5 ml/well) and without inositol supplement. The medium
containing the label is aspirated. DMEM medium (without FCS,
inositol), 20 mM Hepes
(4-(2-hydroxyethyl)-1-piperazine-ethane-sulphonic acid), 1 mg/ml
BSA containing 10 mM LiCl (freshly prepared), are added and
incubated for 10-15 min at 37.degree. C. The agonist (i.e. oxytocin
used at a concentration of 10 nM) and the antagonists (i.e. the
tests compounds of formula (I) can be used in a concentration of 10
.mu.M, 1 .mu.M, 300 nM, 100 nM, 10 nM, 1 nM, 100 pM, 10 pM, 3 pM)
can be added at the required time (15-45 min), followed by
aspiration of the medium. In the presence of OT, the radiolabelled
inositol is converted to radiolabelled IP3. Antagonizing OT at the
OT-receptor inhibits the IP3 formation.
[0211] The amount of the radiolabelled IP3 may be determined
through the ensuing work-up. The reaction is stopped with 1 ml
STOP-solution (i.e. 0.4 M perchloric acid), and let sit for 5-10
min at Room Temperature. Then, 0.8 ml are transferred into tubes
containing 0.4 ml of neutralizing solution (0.72 M KOH/0.6M
KHCO.sub.3), and the tubes vortexed and kept in the cold at least
for 2 h.
[0212] Separation of IP's: The samples are spun in a table top
centrifuge at 3000-4000 rpm for 15 min. 1 ml of the supernatant is
transferred to new tubes containing 2.5 ml H.sub.2O. Packed resin
(Dowex AG1X8) is equilibrated with 20 ml H.sub.2O, and the whole
samples are poured onto the chromatography columns, thus separating
the mixture. To remove free inositol, two washes with 10 ml
H.sub.2O are carried out.
[0213] Elution of total IP's: Elution is achieved using 3 ml 1M
ammonium formate/0.1M formic acid. The eluant is collected in
scintillation counting tubes, after the addition of 7 ml of
scintillation liquid. The amount of [.sup.3H]-IP3 is determined by
a scintillating counter.
[0214] The ability of compounds of formula (I) to effectively
antagonize oxytocin-induced IP3-synthesis mediated by the oxytocin
receptor, can be assessed using the above described in vitro
biological assay. TABLE-US-00003 TABLE 3 Inhibition of IP3-
synthesis, ratOT-R Structure IUPAC-Name IC.sub.50 (.mu.M) ##STR20##
Methyl (2S,4E)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.077 ##STR21## Methyl (2S,4Z)-4-(methoxyimino)-1-[(2'-
methyl[1,1'biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
0.023
d) In vivo Model for Inhibtion of Uterine Contractions
[0215] The assay evaluates the biological effect of tested
compounds in an in vivo model of preterm labor, premature
birth.
[0216] Non-pregnant Charles River CD (SD) BR female rats (9-10
weeks old, 200-250 g) were treated at 18 and 24 hours before the
experiment with 250 .mu.g/kg, i.p. diethylstilbestrol (DES). For
the assay, the animal was anaesthetised with urethane (1.75 g/kg,
i.p.) and placed on a homeothermic operating table. The trachea was
isolated and cannulated with a suitable polyethylene (PE) tubing. A
midline incision at the hypogastrium level was made and one uterine
horn exposed, its cephalic end cannulated with a PE240 tubing and,
after filling the internal cavity with 0.2 ml of sterile
physiological saline, connected to a "Gemini" amplifying/recording
system via a P231D Gould Statham pressure transducer.
[0217] One jugular vein was isolated, cannulated with a PE60 tubing
and connected to a butterfly needle to provide an i.v. route of
administration of the test compounds via a dispensing syringe.
[0218] In the case of intraduodenal administration of the test
compounds, the duodenum can be isolated and similarly cannulated
through a small incision in its wall.
[0219] One carotid artery was also isolated and cannulated with
PE60 catheter and connected to a suitable syringe for blood sample
collection.
[0220] After a stabilization period and throughout the experiment,
the same dose of oxytocin was repeatedly injected intravenously at
30-min intervals. When reproducible contractile responses of the
uterus to the same OT stimulus (selected dose of oxytocin) were
obtained, the dose of the test compound or of the reference
(vehicle) was administered. Further injection cycles of the same
dose of oxytocin, were continued (OT injections at 30-min
intervals) for a suitable time after treatment to assess the
inhibitory effects and the reversibility of these effects.
[0221] The contractile response of the uterus to oxytocin was
quantified by measuring the intra-uterine pressure and the number
of contractions. The effect of the reference and test compounds was
evaluated by comparing pre- and post-treatment pressure values. In
addition, at 2, 30, 90 and 210 minutes after test compound
administration, a 0.5-ml blood sample was withdrawn from the
cannulated carotid artery of each experimental animal. Plasma was
obtained by standard laboratory procedure and the resulting samples
were stored at -20.degree. C.
[0222] The activities of the pyrrolidine derivatives of formula (I)
may be assessed using the above described in vivo biological assay,
Representative values for one example compound are given in Table
4. The values refer to the capacity of the example compound
according to formula (I) to effectively antagonize oxytocin-induced
uterine contractions in the rat. From the values shown in Table 4
it may be derived that said example test compound according to
formula (I) does exhibit a significant activity as tocolytic, i.e.
uterine-relaxing, agent. TABLE-US-00004 TABLE 4 Route of %
Reduction of administration/ Uterine Dose Structure IUPAC-Name
Vehicle Contraction (mg/kg) ##STR22## Methyl
(2S,4Z)-4-(methoxyimino)-1-[(2'-
methyl[1,1'-biphenyl]-4-yl)carbonyl]-2- pyrrolidinecarboxylate
intravenous: PEG400/saline 50:50; 5 ml/kg infusion -35.4 .+-. 7.0
-49.0 .+-. 6.5 -51.8 .+-. 9.2 1 3 10
* * * * *