Note: Descriptions are shown in the official language in which they were submitted.
CA 02287901 1999-10-29
WO 98148798 PCT/US98/08700
-1-
ANTITHROMBOTIC AGENTS
This invention relates to thrombin inhibitors
which are useful anticoagulants in mammals. In particular
it relates to heterocyclic derivatives having high
anticoagulant activity, and antithrombotic activity. Thus,
this invention relates to new inhibitors of thrombin,
pharmaceutical compositions containing the compounds as
active ingredients, and the use of the compounds as
anticoagulants for prophylaxis and treatment of
thromboembolic disorders such as venous thrombosis,
pulmonary embolism, arterial thrombosis, in particular
myocardial ischemia, myocardial infarction and cerebral
thrombosis, general hypercoagulable states and local
hypercoagulable states, such as following angioplasty and
coronary bypass operations, and generalized tissue injury as
it relates to the inflammatory process. In addition, the
antithrombotic agents are useful as anticoagulants in in
vitro applications.
The process of blood coagulation, thrombosis, is
triggered by a complex proteolytic cascade leading to the
formation of thrombin. Thrombin proteolytically removes
activation peptides from the Aa-chains and the B~3-chains of
fibrinogen, which is soluble in blood plasma, initiating
insoluble fibrin formation.
Anticoagulation currently is achieved by the
administration of heparins and coumarins. Parenteral
pharmacological control of coagulation and thrombosis is
based on inhibition of thrombin through the use of heparins.
CA 02287901 1999-10-29
WO 98/48798 PCTNS98/08700
-2-
Heparins act indirectly on thrombin by accelerating the
inhibitory effect of endogenous antithrombin III (the main
physiological inhibitor of thrombin). Because antithrombin
III levels vary in plasma and because clot-bound thrombin
seems resistant to this indirect mechanism, heparins can be
an ineffective treatment. Because coagulation assays are
believed to be associated with efficacy and with safety,
heparin levels must be monitored with coagulation assays
(particularly the activated partial thromboplastin time
(APTT) assay). Coumarins impede the generation of thrombin
by blocking the posttranslational gamma-carboxylation in the
synthesis of prothrombin and other proteins of this type.
Because of their mechanism of action, the effect of
coumarins can only develop slowly, 6-24 hours after
administration. Further, they are not selective
anticoagulants. Coumarins also require monitoring with
coagulation assays (particularly the prothrombin time (PT)
assay) .
Recently, interest has grown in small synthetic
molecules which demonstrate potent direct inhibition of
thrombin. See, for example Robert M. Scarborough, Annual
Reports in Medicinal Chemistry, (1995), 30, 71-80.
Although the heparins and coumarins are effective
anticoagulants, no commercial drug has yet emerged from the
small synthetic molecules; and despite the continuing
promise for this class of compounds, there still exists a
need for anticoagulants which act selectively on thrombin,
and which, independent of antithrombin III, exert inhibitory
action shortly after administration, preferably by an oral
route, and do not interfere with lysis of blood clots, as
required to maintain hemostasis.
The present invention is directed to the discovery
that the compounds of the present invention, as defined
below, are potent thrombin inhibitors that may have high
bioavailability following oral administration.
According to the invention there is provided a
method of inhibiting thrombin comprising using an effective
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08'700
-3-
amount of a thrombin inhibiting compound of formula I (or a
pharmaceutically acceptable salt thereof)
R ~ ~;~~ __ A___~% -- . -Rs
1 ~-- , ~ v _ ;
't i
Rs i ~~.~ S ~~./:.~ z
'I
\\ RZ
wherein
A is carbonyl or methylene;
D is CH, CRd or N in which Rd is formyl,
hydroxymethyl, methyl or methoxy;
E is CH, CRe or N in which Re is methyl, methoxy
or halo;
R2 and R3 are defined together such that
A. R2 is -X2-(CH2)m-NRaRb in which X2 is a direct
bond, methylene or O; m is 1, 2, 3, 4 or 5; provided that
when m is 1, then X2 is a direct bond; and Ra and Rb are
independently hydrogen or (1-3C)alkyl or the group NRaRb is
pyrrolidino, piperidino, or morpholino; and
R3 is -CH2-Rc, in which Rc is 5-tetrazolyl,
2-carboxy-5-oxopyrrolidin-1-yl or 2-[[(1-4C)alkoxy]-
carbonyl]-5-oxopyrrolidin-1-yl; or
R3 is -O-(CH2)e-(CHCH3)f-Rf in which a is 0, 1, 2
or 3 and f is 0 or 1 and the sum of a and f is 1, 2 or 3 and
Rf is as deffined below; or
B. R2 is -X2-(CH2)n-Rf in which X2 is a direct bond,
methylene or O; n is 1, 2, 3 or 4; and Rf is 5-tetrazolyl,
carboxy, [(1-4C)alkoxy]carbonyl or hydroxymethyl; and
R3 is -X3-(CH2)s-NRSRt or -CH2-Rk, in which X3 is
a direct bond, methylene or O; s is 1 or 2; provided that
when s is 1, then X3 is a direct bond; and Rs and Rt are
independently hydrogen or (1-3C)alkyl or the group NRSRt is
pyrrolidino, piperidino, or morpholino; and Rk is
2-oxopyrrolidin-1-yl or 3-(1-oxoethyl)imidazolidin-1-yl; and
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-4-
one of R5 and R6 is hydrogen; and the other of R5
and R6 is hydrogen, hydroxy or methoxy.
A particular compound (or a pharmaceutically
acceptable salt thereof) of formula I is one wherein
A is carbonyl or methylene;
D is CH, CRd or N in which Rd is formyl,
hydroxymethyl, methyl or methoxy;
E is CH, CRe or N in which Re is methyl, methoxy
or halo;
R2 and R3 are defined together such that
A. R2 is -X2-(CH2)m-NRaRb in which X2 is a direct
bond, methylene or O; m is 1, 2, 3, 4 or 5; provided that
when m is 1, then X2 is a direct bond; and Ra and Rb are
independently hydrogen or (1-3C)alkyl or the group NRaRb is
pyrrolidino, piperidino, or morpholino; and
R3 is -CH2-Rc, in which Rc is 5-tetrazolyl,
2-carboxy-5-oxopyrrolidin-1-yl or 2-[[(1-4C)alkoxy]-
carbonyl]-5-oxopyrrolidin-1-yl; or
B. R2 is -X2-(CH2)n-Rf in which X2 is a direct bond,
methylene or O; n is 1, 2 or 3; and Rf is 5-tetrazolyl,
carboxy, [(1-4C)alkoxy]carbonyl or hydroxymethyl; and
R3 is -X3-(CH2)s-NRSRt or -CH2-Rk, in which X3 is
a direct bond, methylene or O; s is 1 or 2; provided that
when s is 1, then X3 is a direct bond; and Rs and Rt are
independently hydrogen or (1-3C)alkyl or the group NRSRt is
pyrrolidino, piperidino, or morpholino; and Rk is
2-oxopyrrolidin-1-yl or 3-(1-oxoethyl)imidazolidin-1-yl;
R5 is hydrogen; and
R6 is hydrogen, hydroxy or methoxy.
A particular value for D is CH.
A particular value for E is CH or CRe in which Re
is methoxy.
A particular set of values when R3 is -CH2-RC is:
RC is 5-tetrazolyl, 2-carboxy-5-oxopyrrolidin-1-yl or
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-5-
2-(ethoxycarbonyl)-5-oxopyrrolidin-1-yl; and R2 is
2-pyrrolidinoethoxy.
A particular set of values when R2 is
-X2-(CH2)n-Rf is: A is methylene, X2 is O; n is 1 or 3; and
Rf is carboxy, [(1-4C)alkoxy]carbonyl in which (1-4C)alkoxy
is methoxy, ethoxy or t-butoxy, or hydroxymethyl.
A particular set of values when R3 is
-X3-(CH2)s-NRSRt is: E is CRe in which Re is methoxy and R3
is pyrrolidinomethyl.
A particular value for R5 is methoxy.
A particular value for R6 is hydroxy.
A more particular value for A is methylene.
The present invention also provides a method of
inhibiting coagulation in a mammal comprising administering
to a mammal in need of treatment, a coagulation inhibiting
dose of a thrombin inhibiting compound of formula I having
any of the above definitions.
The present invention further provides a method of
inhibiting thrombin comprising administering to a mammal in
need of treatment, a thrombin inhibiting dose of a thrombin
inhibiting compound of formula I having any of the above
definitions.
Further, the present invention provides a method
of treating a thromboembolic disorder comprising
administering to a mammal in need of treatment, an effective
dose of a thrombin inhibiting compound of formula I having
any of the above definitions.
In addition, there is provided the use of a
thrombin inhibiting compound of formula I having any of the
above definitions for the manufacture of a medicament for
treatment of a thromboembolic disorders.
As a further aspect of the invention, there is
provided a prodrug (or a pharmaceutically acceptable salt
thereof) of any of the above described thrombin inhibiting
compounds of formula I which will form a prodrug. (It will
be recognized that a thrombin inhibiting compound of formula
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-6-
I also may serve as a prodrug for a different thrombin
inhibiting compound of formula I).
As an additional feature of the invention there is
provided a pharmaceutical formulation comprising in
association with a pharmaceutically acceptable carrier,
diluent or excipient, a prodrug of a thrombin inhibiting
compound of formula I (or of a pharmaceutically acceptable
salt thereof) as provided in any of the above descriptions.
A compound of formula I in which Rf is an ester or
hydroxymethyl group may act directly as a thrombin inhibitor
or indirectly as a result of its biotransformation to a
corresponding compound of formula I in which Rf is carboxy.
In general, the thrombin inhibiting compounds of
formula I are believed to be novel and, thus, to constitute
an additional aspect of the invention. Thus, according to
the invention there is provided a novel compound of formula
I (or a pharmaceutically acceptable salt thereof} according
to any of the above definitions of a compound of formula I,
provided that the compound is not one which is not novel. A
pharmaceutically acceptable salt of an antithrombotic agent
of the instant invention includes one which i.s an acid-
addition salt made with an acid which provides a
pharmaceutically acceptable anion. Thus, an acid addition
salt of a novel compound of formula I as provided above made
with an acid which affords a pharmaceutically acceptable
anion provides a particular aspect of the invention.
Examples of such acids are provided hereinbelow.
As an additional aspect of the invention there is
provided a pharmaceutical formulation comprising in
association with a pharmaceutically acceptable carrier,
diluent or excipient, a novel compound of formula I (or a
pharmaceutically acceptable salt thereof} as provided in any
of the above descriptions.
In this specification, the following definitions
are used, unless otherwise described: Halo is fluoro,
chloro, bromo or iodo. Alkyl, alkoxy, etc. denote both
straight and branched groups; but reference to an individual
CA 02287901 1999-10-29
WO 98148798 PCT/US98/08700
radical such as "propyl" embraces only the straight chain
("normal") radical, a branched chain isomer such as
"isopropyl" being specifically denoted.
It will be appreciated that certain compounds of
formula I (or salts or prodrugs, etc.) may exist in, and be
isolated in, isomeric forms, including cis- or trans-
isomers, as well as optically active, racemic, or
diastereomeric forms. It is to be understood that the
present invention encompasses a compound of formula I as a
mixture of diastereomers, as well as in the form of an
individual diastereomer, and that the present invention
encompasses a compound of formula I as a mixture of
enantiomers, as well as in the form of an individual
enantiomer, any of which mixtures or form possesses
inhibitory properties against thrombin, it being well known
in the art how to prepare or isolate particular forms and
how to determine inhibitory properties against thrombin by
standard tests including those described below.
In addition, a compound of formula I (or salt or
prodrug, etc.) may exhibit polymorphism or may form a
solvate with water or an organic solvent. The present
invention also encompasses any such polymorphic form, any
solvate or any mixture thereof.
Particular values are listed below for radicals,
substituents, and ranges, for illustration only, and they do
not exclude other defined values or other values within
defined ranges for the radicals and substituents.
A particular value for a (1-3C)alkyl group is, for
example, methyl, ethyl, propyl or isopropyl, and for a
(1-4C)alkoxy group is, for example, methoxy, ethoxy,
isopropoxy or t-butoxy.
' A compound of formula I may be made by processes
which include processes known in the chemical art for the
production of known compounds of formula I or of
structurally analogous compounds or by a novel process
described herein. A process for a novel compound of formula
I (or a pharmaceutically acceptable salt thereof), novel
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_g_
processes for a compound of formula I and novel
intermediates for the manufacture of a compound of formula I
as defined above provide further features of the invention
and are illustrated by the following procedures in which the
meanings of the generic radicals are as defined above,
unless otherwise specified. It will be recognized that it
may be preferred or necessary to prepare a compound of
formula I in which a functional group is protected using a
conventional protecting group, then to remove the protecting
group to provide the compound of formula I.
In general, a compound of formula I may be
prepared according to one of the routes outlined in Scheme I
for a compound of formula I in which R5 is hydrogen, and
which are described in the examples, in which each of Q2, Q3
and Q6, respectively, represents a value defined for the
groups R2, R3 and R6, a protected version of such a group,
or moiety which can be further elaborated into such a group.
Final conversion of a group Q2, Q3 or Q6 into R2, R3 or R6
is carried out at a convenient point, consistent with the
chemistry employed. It will be recognized that a number of
other routes may be used, particularly those involving
condensation of an organometallic species to form a compound
of formula C or G in Scheme I, as well as the fact that for
a compound in which R~ is not hydrogen, the corresponding
scheme with compounds bearing a group Q5 at the 5-position
and in which Q6 is hydrogen is appropriate.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-9-
Scheme I
/w I~ .CH O ~ ~-Qs
Qs S N\ a / ~ E/
H02C \ )-Q3 D CHs \ ~ CH
CHs
E
6.1 /
Q S ~ B~Mg \ ~ Q2
s D Q2 D
F
Q3
QE
Q3 C~3
QE QE
n
Thus, there is provided a process for preparing a
novel compound of formula I (or a pharmaceutically
acceptable salt thereof) as provided in any of the above
descriptions which is selected from any of those described
in the examples, including,
(a-1) for a compound of formula I in which R2 is
-X2-(CH2)m-NRaRb or -X2-(CH2)n-Rf in which X2 is O,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-10-
alkylating the hydroxy group of a corresponding phenol of
formula II;
R5 / A ~ ~ Rs
I I -E
II
D~ ~OH
with a group of formula X-(CH2)m-NRaRb or X-(CH2)n-Rf
respectively, or a protected derivative thereof, wherein X
is a conventional leaving group;
(a-2) for a compound of formula I in which R3 is
-O-(CH2)e-(CHCH3)f-Rf or -X3-(CH2)s-NRSRt in which X3 is O,
alkylating the hydroxy group of a corresponding phenol of
formula III;
R5 / A ~ ~>--OH
I I ~E
III
D~ ~R2
with a group of formula X-(CH2)e-(CHCH3)f-Rf or
X-(CH2)s-NRSRt, respectively, or a protected derivative
thereof, wherein X is a conventional leaving group;
(b) for a compound of formula I in which RC is
2-carboxy-5-oxopyrrolidin-1-yl or Rf is carboxy, decomposing
the ester of a corresponding compound of formula I in which
Rc is 2-[[(1-4C)alkoxy]carbonyl]-5-oxopyrrolidin-1-yl or Rf
is [(1-4C)alkoxy]carbonyl, respectively;
(c) for a compound of formula I in which Rf is
hydroxymethyl, reducing the acid or the ester of a
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-11-
corresponding compound of formula I in which Rf is carboxy
or [(1-4C)alkoxy]carbonyl, respectively;
(d) for a compound of formula I in which R3 is
-CH2-Rc in which Rc is 2-[[(1-4C)alkoxy]carbonyl]-5-
oxopyrrolidin-1-yl, or R3 is CH2-NRSRt, or R3 is -CH2-Rk,
alkylating the nitrogen of a corresponding amine of formula
H-Rc, H-NRsRt or H-Rk, respectively, using a bromide
corresponding to the compound of formula I, but in which R3
is -CH2-X, wherein X is a conventional leaving group;
(e) for a compound of formula I in which Rf is
carboxy, hydrolysis of the cyano group of a corresponding
compound but in which Rf is cyano;
(f) for a compound of formula I in which A is
methylene, reductive removal of the hydroxy group of a
corresponding compound but in which A is -CH(OH)-;
(g) for a compound of formula I in which R2 is
-X2-(CH2)m-NRaRb, alkylating the nitrogen of a corresponding
amine of formula H-NRaRb, using a compound corresponding to
the compound of formula I, but in which R2 is -X2-(CH2)m-X
in which X is a conventional leaving group;
(h) for a compound of formula I in which A is
carbonyl, condensation of a reagent of formula IV
R ~ ~ ~ Rs
5
\=E
w
R6 \ S~N~
with a Gringard reagent of formula V
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-12-
YMg
w
D R2
(or a protected derivative thereof) wherein Y is chloro,
bromo or iodo;
(i) for a compound of formula I in which Rf is
5-tetrazolyl, cycloaddition of a corresponding compound but
in which Rf is cyano with an azide reagent;
(j) for a compound of formula I in which A is
carbonyl, acylation of a compound of formula VI
R5
VI
RE
a R2
HO
R3
o -E
VII
or from the corresponding nitrile;
(k) for a compound of formula I in which R2 is
-X2-(CH2)n-Rf in which X2 is a direct bond and n is 2,
reducing the double bond of a corresponding compound but in
which R2 is -CH=CH-Rf;
whereafter, for any of the above procedures, when
a functional group is protected using a protecting group,
removing the protecting group;
with a Friedel-Crafts reagent derived from an acid of
formula VII
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-13-
whereafter, for any of the above procedures, when
a pharmaceutically acceptable salt of a compound of formula
I is required, it may be obtained by reacting the basic form
of such a compound of formula I with an acid affording a
physiologically acceptable counterion, or, for a compound of
formula I which bears an acidic moiety, reacting the acidic
form of such a compound of formula I with a base which
affords a pharmaceutically acceptable canon, or by any
other conventional procedure.
As used herein, a leaving group is a moiety which
is displaced in a nucleophilic substitution reaction, for
example a halo group (such as chloro, bromo or iodo), a
sulfonate ester group (such as methylsulfonyloxy, p-toluyl-
sulfonyloxy or trifluoromethylsulfonyloxy), or the reactive
species derived from treating an alcohol with triphenyl-
phospine, diethyl azodicarboxylate and triethyl amine (in a
Mitsunobu reaction).
Novel intermediate or starting material compounds,
such as a novel phenol of formula II or formula III provide
a further aspect of the invention.
As mentioned above, a compound corresponding to a
compound of formula I but in which a functional group is
protected may serve as an intermediate for a compound of
formula I. Accordingly, such protected intermediates for a
novel compound of formula I provide further aspects of the
invention. Thus, as one particular aspect of the invention,
there is provided a compound corresponding to a novel
compound of formula I as defined above in which R6 which is
hydroxy, but in which the corresponding substituent is -ORP
in place of hydroxy, wherein RP is a phenol protecting group
other than methyl. Phenol protecting groups are well known
in the art, for example as described in T.W. Greene and
P.G.M. Wuts, "Protecting Groups in Organic Synthesis"
(1991). Particular values of RP include, for example,
benzyl and allyl. Further, RP may denote a functionalized
resin, for example as disclosed in H.V. Meyers, et al.,
Molecular Diversitv, (1995), 1, 13-20.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-14-
As mentioned above, the invention includes
pharmaceutically acceptable salts of the thrombin inhibiting
compounds defined by the above formula I. A compound of
formula I which bears an acidic moiety forms salts with
pharmaceutically acceptable bases. Such a pharmaceutically
acceptable salt may be made with a base which affords a
pharmaceutically acceptable cation, which includes alkalai
metal salts (especially sodium and potassium), alkaline
earth metal salts (especially calcium and magnesium),
aluminum salts and ammonium salts, as well as salts made
from physiologically acceptable organic bases such as
triethylamine, morpholine, piperidine and triethanolamine.
The potassium and sodium salt forms are particularly
preferred.
A particular compound of of formula I which
possesses one or more sufficiently basic functional groups
to react with any of a number of inorganic and organic acids
affording a physiologically acceptable counterion forms a
pharmaceutically acceptable acid addition salt. Acids
commonly employed to form pharmaceutically acceptable acid
addition salts are inorganic acids such as hydrochloric
acid, hydrobromic acid, hydroiodic acid, sulfuric acid,
phosphoric acid, and the like, and organic acids such as
p-toluenesulfonic acid, methanesulfonic acid, oxalic acid,
p-bromobenzenesulfonic acid, carbonic acid, succinic acid,
citric acid, benzoic acid, acetic acid, and the like.
Examples of such pharmaceutically acceptable salts thus are
the sulfate, pyrosulfate, bisulfate, sulfite, bisulfate,
phosphate, monohydrogenphosphate, dihydrogenphosphate,
metaphosphate, pyrophosphate, chloride, bromide, iodide,
acetate, propionate, decanoate, caprylate, acrylate,
formate, isobutyrate, caproate, heptanoate, propiolate,
oxalate, malonate, succinate, suberate, sebacate, fumarate,
maleate, butyne-1,4-dioate, hexyne-1,6-dioate, benzoate,
chlorobenzoate, methylbenzoate, dinitrobenzoate,
hydroxybenzoate, methoxybenzoate, phthalate, sulfonate,
xylenesulfonate, phenylacetate, phenylpropionate,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-15-
phenylbutyrate, citrate, lactate, gamma-hydroxybutyrate,
glycollate, tartrate, methanesulfonate, propanesulfonate,
naphthalene-1-sulfonate, naphthalene-2-sulfonate, mandelate,
and the like. Preferred pharmaceutically acceptable acid
addition salts include those formed with mineral acids such
as hydrochloric acid, hydrobromic acid and sulfuric acid.
If not commercially available, the necessary
starting materials for the preparation of a compound of
formula I may be prepared by procedures which are selected
from standard techniques of organic chemistry, including
aromatic and heteroaromatic substitution and transformation,
from techniques which are analogous to the syntheses of
known, structurally similar compounds, and techniques which
are analogous to the above described procedures or
procedures described in the Examples. It will be clear to
one skilled in the art that a variety of sequences is
available for the preparation of the starting materials.
Starting materials which are novel provide another aspect of
the invention.
Selective methods of protection and deprotection
are well known in the art for preparation of compounds such
as those corresponding to a compond of formula I but in
which Rb is ORp discussed above. Selective methods for
cleavage of methyl ethers, as described in the examples, are
discussed in Jones, et al., J. Med. Chem., (1984), 27, 1057-
1066. For example, the diether 3-(4-methoxybenzoyl)-
2-(4-methoxyphenyl)benzo[b]thiophene may be treated with
boron tribromide in dichloromethane at -10 °C (1 hour) to
afford the monoether 2-(4-hydroxyphenyl)-3-(4-methoxy-
benzoyl)benzo[b)thiophene, whereas treatment with sodium
thioethoxide affords the isomeric monoether 3-(4-hydroxy-
benzoyl)-2-(4-methoxyphenyl)benzo[b]thiophene. Treatment
with boron tribromide under less mild conditions (0° °C,
6 hours) or with aluminum chloride and ethanethiol cleaves
both ethers.
Generally, the compounds of the invention are
isolated best in the form of acid addition salts. Salts of
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-16-
the compounds of formula I formed with acids such as those
mentioned above are useful as pharmaceutically acceptable
salts for administration of the antithrombotic agents and
for preparation of formulations of these agents. Other acid
addition salts may be prepared and used in the isolation and
purification of the compounds.
As noted above, the optically active isomers and
diastereomers of the compounds of formula I are also
considered part of this invention. Such optically active
isomers may be prepared from their respective optically
active precursors by the procedures described above, or by
resolving the racemic mixtures. This resolution can be
carried out by derivatization with a chiral reagent followed
by chromatography or by repeated crystallization. Removal
of the chiral auxiliary by standard methods affords
substantially optically pure isomers of the compounds of the
present invention or their precursors. Further details
regarding resolutions can be obtained in Jacques, et al.,
Enantiomers, Racemates, and Resolutions, John Wiley & Sons,
1981.
The compounds of the invention are believed to
selectively inhibit thrombin over other proteinases and
nonenzyme proteins involved in blood coagulation without
appreciable interference with the body's natural clot lysing
ability (the compounds have a low inhibitory effect on
fibrinolysis). Further, such selectivity is believed to
permit use with thrombolytic agents without substantial
interference with thrombolysis and fibrinolysis.
The invention in one of its aspects provides a
method of inhibiting thrombin in mammals comprising
administering to a mammal in need of treatment an effective
(thrombin inhibiting) dose of a compound of formula I.
In another of its aspects, the invention provides
a method of treating a thromboembolic disorder comprising
administering to a mammal in need of treatment an effective
(thromboembolic disorder therapeutic and/or prophylactic
amount) dose of a compound of formula I.
CA 02287901 1999-10-29
WO 98/48798 PCTNS98/08700
-17-
The invention in another of its aspects provides a
method of inhibiting coagulation in mammals comprising
administering to a mammal in need of treatment an effective
(coagulation inhibiting) dose of a compound of formula I.
The thrombin inhibition, coagulation inhibition
and thromboembolic disorder treatment contemplated by the
present method includes both medical therapeutic and/or
prophylactic treatment as appropriate.
In a further embodiment the invention relates to
treatment, in a human or animal, of conditions where
inhibition of thrombin is required. The compounds of the
invention are expected to be useful in animals, including
man, in treatment or prophylaxis of thrombosis and
hypercoagulability in blood and tissues. Disorders in which
the compounds have a potential utility are in treatment or
prophylaxis of thrombosis and hypercoagulability in blood
and tissues. Disorders in which the compounds have a
potential utility, in treatment and/or prophylaxis, include
venous thrombosis and pulmonary embolism, arterial
thrombosis, such as in myocardial ischemia, myocardial
infarction, unstable angina, thrombosis-based stroke and
peripheral arterial thrombosis. Further, the compounds have
expected utility in the treatment or prophylaxis of
atherosclerotic disorders (diseases) such as coronary
arterial disease, cerebral arterial disease and peripheral
arterial disease. Further, the compounds are expected to be
useful together with thrombolytics in myocardial infarction.
Further, the compounds have expected utility in prophylaxis
for reocclusion after thrombolysis, percutaneous
transluminal angioplasty (PTCA) and coronary bypass
operations. Further, the compounds have expected utility in
prevention of rethrombosis after microsurgery. Further, the
compounds are expected to be useful in anticoagulant
treatment in connection with artificial organs and cardiac
valves. Further, the compounds have expected utility in
anticoagulant treatment in hemodialysis and disseminated
intravascular coagulation. A further expected utility is in
CA 02287901 1999-10-29
WO 98/48798 PCTlUS98/08700
-18-
rinsing of catheters and mechanical devices used in patients
in vivo, and as an anticoagulant for preservation of blood,
plasma and other blood products in vitro. Still further,
the compounds have expected utility in other diseases where
blood coagulation could be a fundamental contributing
process or a source of secondary pathology, such as cancer,
including metastasis, inflammatory diseases, including
arthritis, and diabetes. The anti-coagulant compound is
administered orally, parenterally e.g. by intravenous
infusion (iv), intramuscular injection (im) or
subcutaneously (sc).
The specific dose of a compound administered
according to this invention to obtain therapeutic and/or
prophylactic effects will, of course, be determined by the
particular circumstances surrounding the case, including,
for example, the compound administered, the rate of
administration, the route of administration, and the
condition being treated.
A typical daily dose for each of the above
utilities is between about 0.01 mg/kg and about 1000 mg/kg.
The dose regimen may vary e.g. for prophylactic use a single
daily dose may be administered or multiple doses such as 3
or 5 times daily may be appropriate. In critical care
situations a compound of the invention is administered by iv
infusion at a rate between about 0.01 mg/kg/h and about 20
mg/kg/h and preferably between about 0.1 mg/kg/h and about 5
mg/kg/h.
The method of this invention also is practiced in
conjunction with a clot lysing agent e.g. tissue plasminogen
activator (t-PA), modified t-PA, streptokinase or urokinase.
In cases when clot formation has occurred and an artery or
vein is blocked, either partially or totally, a clot lysing
agent is usually employed. A compound of the invention can
be administered prior to or along with the lysing agent or
subsequent to its use, and preferably further is
administered along with aspirin to prevent the reoccurrence
of clot formation.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-19-
The method of this invention is also practiced in
conjunction with a platelet glycoprotein receptor (IIb/IIIa)
antagonist, that inhibits platelet aggregation. A compound
of the invention can be administered prior to or along with
the IIb/IIIa antagonist or subsequent to its use to prevent
the occurrence or reoccurrence of clot formation.
The method of this invention is also practiced in
conjunction with aspirin. A compound of the invention can
be administered prior to or along with aspirin or subsequent
to its use to prevent the occurrence or reoccurrence of clot
formation. As stated above, preferably a compound of the
present invention is administered in conjunction with a clot
lysing agent and aspirin.
This invention also provides pharmaceutical
formulations for use in the above described therapeutic
method. Pharmaceutical formulations of the invention
comprise an effective thrombin inhibiting amount of a
compound of formula I in association with a pharmaceutically
acceptable carrier, excipient or diluent. For oral
administration the antithrombotic compound is formulated in
gelatin capsules or tablets which may contain excipients
such as binders, lubricants, disintegration agents and the
like. For parenteral administration the antithrombotic is
formulated in a pharmaceutically acceptable diluent e.g.
physiological saline (0.9 percent), 5 percent dextrose,
Ringer's solution and the like.
The compound of the present invention can be
formulated in unit dosage formulations comprising a dose
between about 0.1 mg and about 1000 mg. Preferably the
compound is in the form of a pharmaceutically acceptable
salt such as for example the sulfate salt, acetate salt or a
phosphate salt. An example of a unit dosage formulation
comprises 5 mg of a compound of the present invention as a
pharmaceutically acceptable salt in a 10 mL sterile glass
ampoule. Another example of a unit dosage formulation
comprises about 10 mg of a compound of the present invention
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-20-
as a pharmaceutically acceptable salt in 20 mL of isotonic
saline contained in a sterile ampoule.
The compounds can be administered by a variety of
routes including oral, rectal, transdermal, subcutaneous,
intravenous, intramuscular, and intranasal. The compounds
of the present invention are preferably formulated prior to
administration. Another embodiment of the present invention
is a pharmaceutical formulation comprising an effective
amount of a novel compound of formula I or a
pharmaceutically acceptable salt or solvate thereof in
association with a pharmaceutically acceptable carrier,
diluent or excipient therefor.
The active ingredient in such formulations
comprises from 0.1 percent to 99.9 percent by weight of the
formulation. By "pharmaceutically acceptable" it is meant
the carrier, diluent or excipient must be compatible with
the other ingredients of the formulation and not deleterious
to the recipient thereof.
The present pharmaceutical formulations are
prepared by known procedures using well known and readily
available ingredients. The compositions of this invention
may be formulated so as to provide quick, sustained, or
delayed release of the active ingredient after
administration to the patient by employing procedures well
known in the art. In making the compositions of the present
invention, the active ingredient will usually be admixed
with a carrier, or diluted by a carrier, or enclosed within
a carrier which may be in the form of a capsule, sachet,
paper or other container. When the carrier serves as a
diluent, it may be a solid, semi-solid or liquid material
which acts as a vehicle, excipient or medium for the active
ingredient. Thus, the compositions can be in the form of
tablets, pills, powders, lozenges, sachets, cachets,
elixirs, suspensions, emulsions, solutions, syrups,
aerosols, (as a solid or in a liquid medium), soft and hard
gelatin capsules, suppositories, sterile injectable
solutions, sterile packaged powders, and the like.
CA 02287901 1999-10-29
WO 98/48798 PC'f/US98/08700
-21-
The following formulation examples are
illustrative only and are not intended to limit the scope of
the invention in any way. "Active ingredient," of course,
means a compound according to Formula I or a
pharmaceutically acceptable salt or solvate thereof.
Formulation 1: Hard gelatin capsules are prepared
using the following ingredients:
Quantity
(m~psule)
Active ingredient 250
Starch, dried 200
Magnesium stearate 10
Total 460 mg
Formulation 2: A tablet is prepared using the
ingredients below:
Quantity
(mg/tablet)
Active ingredient 250
Cellulose, microcrystalline 400
Silicon dioxide, fumed 10
Stearic acid 5
Total 665 mg
The components are blended and compressed to form tablets
each weighing 665 mg.
Formulation 3: An aerosol solution is prepared
containing the following components:
weight
Active ingredient 0.25
Ethanol 25.75
Propellant 22 (Chlorodifluoromethane) 70.00
Total 100.00
The active compound is mixed with ethanol and the mixture
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-22-
added to a portion of the propellant 22, cooled to -30 °C
and transferred to a filling device. The required amount is
then fed to a stainless steel container and diluted with the
remainder of the propellant. The valve units are then
fitted to the container.
Formulation 4: Tablets, each containing 60 mg of
active ingredient, are made as follows:
Active ingredient 60 mg
Starch 45 mg
Microcrystalline cellulose 35 mg
Polyvinylpyrrolidone (as 10 % solution in 4 mg
water?
Sodium carboxymethyl starch 4.5 mg
Magnesium stearate 0.5 mg
Talc 1 mct
Total 150 mg
The active ingredient, starch and cellulose are passed
through a No. 45 mesh U.S. sieve and mixed thoroughly. The
aqueous solution containing polyvinylpyrrolidone is mixed
with the resultant powder, and the mixture then is passed
through a No. 14 mesh U.S. sieve. The granules so produced
are dried at 50 °C and passed through a No. 18 mesh U.S.
Sieve. The sodium carboxymethyl starch, magnesium stearate
and talc, previously passed through a No. 60 mesh U.S.
sieve, are then added to the granules which, after mixing,
are compressed on a tablet machine to yield tablets each
weighing 150 mg.
Formulation 5: Capsules, each containing 80 mg of
active ingredient, are made as follows:
Active ingredient 80 mg
Starch 59 mg
Microcrystalline cellulose 59 mg
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-23-
Magnesium stearate 2 ma
Total 200 mg
The active ingredient, cellulose, starch, and magnesium
stearate are blended, passed through a No. 45 mesh U.S.
sieve, and filled into hard gelatin capsules in 200 mg
quantities.
Formulation 6: Suppositories, each containing
225 mg of active ingredient, are made as follows:
Active ingredient 225 mg
Saturated fatty acid glycerides 2,000 ma
Total 2,225 mg
The active ingredient is passed through a No. 60 mesh U.S.
sieve and suspended in the saturated fatty acid glycerides
previously melted using the minimum heat necessary. The
mixture is then poured into a suppository mold of nominal 2
g capacity and allowed to cool.
Formulation 7: Suspensions, each containing 50 mg
of active ingredient per 5 ml dose, are made as follows:
Active ingredient 50 mg
Sodium carboxymethyl cellulose 50 mg
Syrup 1.25 mL
Benzoic acid solution 0.10 mL
Flavor q.v.
Color q.v.
Purified water to total 5 mL
The active ingredient is passed through a No. 45 mesh U.S.
sieve and mixed with the sodium carboxymethyl cellulose and
syrup to form a smooth paste. The benzoic acid solution,
flavor and color are diluted with a portion of the water and
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-24-
added, with stirring. Sufficient water is then added to
produce the required volume.
Formulation 8: An intravenous formulation may be
prepared as follows:
Active ingredient 100 mg
Isotonic saline 1,000 mL
The solution of the above ingredients generally is
administered intravenously to a subject at a rate of 1 mL
per minute.
The ability of the compounds of the present
invention to be an effective and orally active thrombin
inhibitor are evaluated in one or more of the following
assays.
The compounds provided by the invention
(formula I) selectively inhibit the action of thrombin in
mammals. The inhibition of thrombin is demonstrated by in
vitro inhibition of the amidase activity of thrombin as
measured in an assay in which thrombin hydrolyzes the
chromogenic substrate, N-benzoyl-L-phenylalanyl-L-valyl-L-
arginyl-p-nitroanilide, N-benzoyl-L-Phe-L-Val-L-Arg-p-
nitroanilide.
The assay is carried out by mixing 50 ~,L buffer
(0.03M Tris, 0.15M NaCl, pH 7.4) with 25 ~.L of human
thrombin solution (purified human thrombin, Enzyme Research
Laboratories, South Bend, Indiana, at 8 NIH units/mL) and
25 ~,L of test compound in a solvent (50% aqueous methanol
(v:v)). Then 150 ~.L of an aqueous solution of the
chromogenic substate (at 0.25 mg/mL) are added and the rates
of hydrolysis of the substrate are measured by monitoring
the reactions at 405 nm for the release of p-nitroaniline.
Standard curves are constructed by plotting free thrombin
concentration against hydrolysis rate. The hydrolysis rates
observed with test compounds are then converted to "free
thrombin" values in the respective assays by use of the
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-25-
standard curves. The bound thrombin (bound to test
compound) is calculated by subtracting the amount of free
thrombin observed in each assay from the known initial
amount of thrombin used in the assay. The amount of free
inhibitor in each assay is calculated by subtracting the
number of moles of bound thrombin from the number of moles
of added inhibitor (test compound).
The Kass value is the hypothetical equilibrium
constant for the reaction between thrombin and the test
compound (I).
Thrombin + I ~ Thrombin-I
Kass= Thrombin-I]
[(Thrombin) x (I)]
Kass is calculated for a range of concentrations
of test compounds and the mean value reported in units of
liter per mole. In general, a thrombin inhibiting compound
of formula I of the instant invention exhibits a Kass of
0.05 X 106 L/mole or much greater.
By substantially following the procedures
described above for human thrombin, and using other human
blood coagulation system serine proteases and using
fibrinolytic system serine proteases, with the appropriate
chromogenic substrates, identified below, the selectivity of
the compounds of the present invention with respect to the
coagulation factor serine proteases and to the fibronolytic
serine proteases are evaluated as well as their substantial
lack of interference with human plasma clot fibrinolysis.
Human factors X, Xa, IXa, XIa, and XIIa are
purchased from Enzyme Research Laboratories, South Bend,
Indiana; human urokinase from Leo Pharmaceuticals, Denmark;
and recombinant activated Protein C (aPC) is prepared at Eli
Lilly and Co. substantially according to U.S. Patent
4,981,952. Chromogenic substrates: N-Benzoyl-Ile-Glu-Gly-
Arg-p-nitroanilide (for factor Xa); N-Cbz-D-Arg-Gly-Arg-p-
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-26-
nitroanilide (for factor IXa assay as the factor Xa
substrate); Pyroglutamyl-Pro-Arg-p-nitroanilide (for Factor
XIa and for aPC); H-D-Pro-Phe-Arg-p-nitroanilide (for factor
XIIa); and Pyroglutamyl-Gly-Arg-p-nitroanilide (for
urokinase); are purchased from Kabi Vitrum, Stockholm,
Sweden, or from Midwest Biotech, Fishers, Indiana. Bovine
trypsin is purchased from Worthington Biochemicals,
Freehold, New Jersey, and human plasma kallikrein from Kabi
Vitrum, Stockholm, Sweden. Chromogenic substrate H-D-Pro-
Phe-Arg-p-nitroanilide for plasma kallikrein is purchased
from Kabi Vitrum, Stockholm, Sweden. N-Benzoyl-Phe-Val-Arg-
p-nitroanilide, the substrate for human thrombin and for
trypsin, is synthesized according to procedures described
above for the compounds of the present invention, using
known methods of peptide coupling from commercially
available reactants, or purchased from Midwest Biotech,
Fishers, Indiana.
Human plasmin is purchased from Boehringer
Mannheim, Indianapolis, Indiana; nt-PA is purchased as
single chain activity reference from American Diagnostica,
Greenwich, Connecticut; modified-t-PA6 (mt-PA6) is prepared
at Eli Lilly and Company by procedure known in the art (See,
Burck, et al., J. Biol. Chem., 265, 5120-5177 (1990).
Plasmin chromogenic substrate H-D-Val-Leu-Lys-p-nitroanilide
and tissue plasminogen activator (t-PA) substrate H-D-Ile-
Pro-Arg-p-nitroanilide are purchased from Kabi Vitrum,
Stockholm, Sweden.
In the chromogenic substrates described above the
three-letter symbols Ile, Glu, Gly, Pro, Arg, Phe, Val, Leu
and Lys are used to indicate the corresponding amino acid
group isoleucine, glutamic acid, glycine, proline, arginine,
phenylalanine, valine, leucine and lysine, respectively.
Thrombin inhibitors preferably should spare
fibrinolysis induced by urokinase, tissue plasminogen
activator (t-PA) and steptokinase. This would be important
to the therapeutic use of such agents as an adjunct to
streptokinase, t-PA or urokinase thrombolytic therapy and to
CA 02287901 1999-10-29
WO 98148798 PCT/US98/08700
-27-
the use of such agents as an endogenous fibrinolysis-sparing
(with respect to t-PA and urokinase) antithrombotic agents.
In addition to the lack of interference with the amidase
activity of the fibrinolytic proteases, such fibrinolytic
system sparing can be studied by the use of human plasma
clots and their lysis by the respective fibrinolytic
plasminogen activators.
Materials
Dog plasma is obtained from conscious mixed-breed hounds
(either sex Butler Farms, Clyde, New York, U.S.A.) by
venipuncture into 3.8 percent citrate. Fibrinogen is
prepared from fresh dog plasma and human fibrinogen is
prepared from in-date ACD human blood at the fraction I-2
according to previous procedures and specifications. Smith,
Biochem. J., 185, 1-11 (1980); and Smith, et al.,
Biochemistry, 11, 2958-2967, (1972). Human fibrinogen (98
percent pure/plasmin free) is from American Diagnostica,
Greenwich, Connecticut. Radiolabeling of fibrinogen I-2
preparations is performed as previously reported. Smith, et
al., Biochemistry, 11, 2958-2967, (1972). Urokinase is
purchased from Leo Pharmaceuticals, Denmark, as 2200 Ploug
units/vial. Streptokinase is purchased from Hoechst-Roussel
Pharmaceuticals, Somerville, New Jersey.
Methods - Effects on Lysis of Human Plasma Clots by t-PA
Human plasma clots are formed in micro test tubes by adding
50 ~,L thrombin (73 NIH unit/mL) to 100 ~,L human plasma which
contains 0.0229 ~,Ci 125-iodine labeled fibrinogen. Clot
lysis is studied by overlaying the clots with 50 ~,L of
urokinase or streptokinase (50, 100, or 1000 unit/mL) and
incubating for 20 hours at room temperature. After
incubation the tubes are centrifuged in a Beckman Microfuge.
25 ~.L of supernate is added into 1.0 mL volume of 0.03 M
tris/0.15 M NaCl buffer for gamma counting. Counting
controls 100 percent lysis are obtained by omitting thrombin
(and substituting buffer). The thrombin inhibitors are
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-28-
evaluated for possible interference with fibrinolysis by
including the compounds in the overlay solutions at 1, 5,
and 10 ~,g/mL concentrations. Rough approximations of IC50
values are estimated by linear extrapolations from data
points to a value which would represent 50 percent of lysis
for that particular concentration of fibrinolytic agent.
Anticoagulant Activity
Materials
Dog plasma and rat plasma are obtained from conscious mixed-
breed hounds (either sex, Butler Farms, Clyde, New York,
U.S.A.) or from anesthetized male Sprague-Dawley rats
(Harlan Sprague-Dawley, Inc., Indianapolis, Indiana, U.S.A.)
by venipuncture into 3.8 percent citrate. Fibrinogen is
prepared from in-date ACD human blood as the fraction I-2
according to previous procedures and specifications. Smith,
Biochem. J., 185, 1-11 (1980); and Smith, et al.,
Biochemistrv, 11, 2958-2967 (1972). Human fibrinogen is
also purchased as 98 percent pure/plasmin free from American
Diagnostica, Greenwich, Connecticut. Coagulation reagents
Actin, Thromboplastin, Innovin and Human plasma are from
Baxter Healthcare Corp., Dade Division, Miami, Florida.
Bovine thrombin from Parke-Davis (Detroit, Michigan) is used
for coagulation assays in plasma.
Methods
Anticoaaulation Determinations
Coagulation assay procedures are as previously described.
Smith, et al., Thrombosis Research, 50, 163-174 (1988). A
CoAScreener coagulation instrument (American LABor, Inc.) is
used for all coagulation assay measurements. The
prothrombin time (PT) is measured by adding 0.05 mL saline
and 0.05 mL Thromboplastin-C reagent or recombinant human
tissue factor reagent (Innovin) to 0.05 mL test plasma. The
activated partial thromboplastin time (APTT) is measured by
incubation of 0.05 mL test plasma with 0.05 mL Actin reagent
for 120 seconds followed by 0.05 mL CaCl2 (0.02 M). The
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-29-
thrombin time (TT) is measured by adding 0.05 mL saline and
0.05 mL thrombin (10 NIH units/mL) to 0.05 mL test plasma.
The compounds of formula I are added to human or animal
plasma over a wide range of concentrations to determine
prolongation effects on the APTT, PT, and TT assays. Linear
extrapolations are performed to estimate the concentrations
required to double the clotting time for each assay.
Animals
Male Sprague Dawley rats (350-425 gm, Harlan Sprague Dawley
Inc., Indianapolis, IN) are anesthetized with xylazine (20
mg/kg, s.c.) and ketamine (120 mg/kg, s.c.) and maintained
on a heated water blanket (37 °C). The jugular veins) is
cannulated to allow for infusions.
Arterio-Venous shunt model
The left jugular vein and right carotid artery are
cannulated with 20 cm lengths of polyethylene PE 60 tubing.
A 6 cm center section of larger tubing (PE 190) with a
cotton thread (5 cm) in the lumen, is friction fitted
between the longer sections to complete the arterio-venous
shunt circuit. Blood is circulated through the shunt for 15
min before the thread is carefully removed and weighed. The
weight of a wet thread is subtracted from the total weight
of the thread and thrombus (see J.R. Smith, Br J Pharmacol,
77:29, 1982). In this model preferred compounds of the
instant invention reduce the net clot weight to
approximately 25-30% of control, or even lower, at an i.v.
dose of 33.176 ~.mol/kg/h.
FeCl3 model of arterial iniury
The carotid arteries are isolated via a midline ventral
cervical incision. A thermocouple is placed under each
artery and vessel temperature is recorded continuously on a
strip chart recorder. A cuff of tubing (0.058 ID x 0.077 OD
x 4 mm, Baxter Med. Grade Silicone), cut longitudinally, is
placed around each carotid directly above the thermocouple.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-30-
FeCl3 hexahydrate is dissolved in water and the
concentration (20 percent) is expressed in terms of the
actual weight of FeCl3 only. To injure the artery and
induce thrombosis, 2.85 uL is pipetted into the cuff to
bathe the artery above the thermocouple probe. Arterial
occlusion is indicated by a rapid drop in temperature. The
time to occlusion is reported in minutes and represents the
elapsed time between application of FeCl3 and the rapid drop
in vessel temperature (see K.D. Kurz, Thromb. Res., 60:269,
1990 ) .
Spontaneous thrombolysis model
In vitro data suggests that thrombin inhibitors inhibit
thrombin and, at higher concentrations, may inhibit other
serine proteases, such as plasmin and tissue plasminogen
activator. To assess if the compounds inhibit fibrinolysis
in vivo, the rate of spontaneous thrombolysis is determined
by implanting a labeled whole blood clot into the pulmonary
circulation. Rat blood (1 mL) is mixed rapidly with bovine
thrombin (4 IU, Parke Davis) and 1251 human Fibrogen (5 ~Ci,
ICN), immediately drawn into silastic tubing and incubated
at 37 °C for 1 hour. The aged thrombus is expelled from the
tubing, cut into 1 cm segments, washed 3X in normal saline
and each segment is counted in a gamma counter. A segment
with known counts is aspirated into a catheter that is
subsequently implanted into the jugular vein. The catheter
tip is advanced to the vicinity of the right atrium and the
clot is expelled to float into the pulmonary circulation.
One hour after implant, the heart and lungs are harvested
and counted separately. Thrombolysis is expressed as a
percentage where:
% Thrombolysis = (infected cpm - lung cpm) x 100
injected cpm
CA 02287901 1999-10-29
WO 98/48798 PCTNS98/08700
-31-
The fibrinolytic dissolution of the implanted clot occurs
time-dependently (see J.P. Clozel, Cardiovas. Pharmacol.,
12:520, 1988).
Coagulation parameters
Plasma thrombin time (TT) and activated partial
thromboplastin time (APTT) are measured with a fibrometer.
Blood is sampled from a jugular catheter and collected in
syringe containing sodium citrate (3.8 percent, 1 part to 9
parts blood). To measure TT, rat plasma (0.1 mL) is mixed
with saline (0.1 mL) and bovine thrombin (0.1 mL, 30 U/mL in
TRIS buffer; Parke Davis) at 37 °C. For APTT, plasma (0.1
mL) and APTT solution (0.1 mL, Organon Teknika) are
incubated for 5 minutes (37 °C) and CaCl2 (0.1 mL, 0.025 M)
is added to start coagulation. Assays are done in duplicate
and averaged.
Index of Bioavailability
For a measure of bioactivity, plasma thrombin time (TT)
serves as a substitute for the assay of parent compound on
the assumption that observed increments in TT resulted from
thrombin inhibition by parent only. The time course of the
effect of the thrombin inhibitor upon TT is determined after
i.v bolus administration to anesthetized rats and after oral
treatment of fasted conscious rats. Due to limitations of
blood volume and the number of points required to determine
the time course from time of treatment to the time when the
response returns to pretreatment values, two populations of
rats are used. Each sample population represents
alternating sequential time points. The average TT over the
time course is used to calculate area under the curve (AUC).
The index of bioavailability is calculated by the formula
shown below and is expressed as percent relative activity.
The area under the curve (AUC) of the plasma TT
time course is determined and adjusted for the dose. This
index of bioavailability is termed "% Relative Activity" and
is calculated as
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-32-
~k Relative Activity = AUC po X Dose a.v X 100
AUC iv Dose po
Compounds
Compound solutions are prepared fresh daily in normal saline
and are injected as a bolus or are infused starting 15
minutes before and continuing throughout the experimental
perturbation which is 15 minutes in the arteriovenous shunt
model and 60 minutes in the FeCl3 model of arterial injury
and in the spontaneous thrombolysis model. Bolus injection
volume is 1 mL/kg for i.v., and 5 mL/kg for p.o., and
infusion volume is 3 mL/hr.
Statistics
Results are expressed as means +/- SEM. One-way analysis of
variance is used to detect statistically significant
differences and then Dunnett's test is applied to determine
which means are different. Significance level for rejection
of the null hypothesis of equal means is P<0.05.
Animals
Male dogs (Beagles; 18 months - 2 years; 12-13 kg, Marshall
Farms, North Rose, New York 14516) are fasted overnight and
fed Purina certified Prescription Diet (Purina Mills, St.
Louis, Missouri) 240 minutes after dosing. Water is
available ad libitum. The room temperature is maintained
between 66-74 °F; 45-50 percent relative humidity; and
lighted from 0600-1800 hours.
Pharmacokinetic model.
Test compound is formulated immediately prior to dosing by
dissolving in sterile 0.9 percent saline to a 5 mg/mL
preparation. Dogs are given a single 2 mg/kg dose of test
compound by oral gavage. Blood samples (4.5 mL) are taken
from the cephalic vein at 0.25, 0.5, 0.75, 1, 2, 3, 4 and 6
hours after dosing. Samples are collected in citrated
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-33-
Vacutainer tubes and kept on ice prior to reduction to
plasma by centrifugation. Plasma samples are analyzed by
HPLC MS. Plasma concentration of test compound is recorded
and used to calculate the pharmacokinetic parameters:
elimination rate constant, Ke; total clearance, Clt; volume
of distribution, VD; time of maximum plasma test compound
concentration, Tmax; maximum concentration of test compound
of Tmax, Cmax; plasma half-life, to.s; and area under the
curve, A.U.C.; fraction of test compound absorbed, F.
Canine Model of Coronary Arte ~ Thrombosis
Surgical preparation and instrumentation of the dogs are as
described in Jackson, et al., Circulation, 82, 930-940
(1990). Mixed-breed hounds (aged 6-7 months, either sex,
Butler Farms, Clyde, New York) are anesthetized with sodium
pentobarbital (30 mg/kg intravenously, i.v.), intubated, and
ventilated with room air. Tidal volume and respiratory
rates are adjusted to maintain blood P02, PCO2, and pH
within normal limits. Subdermal needle electrodes are
inserted for the recording of a lead II ECG.
The left jugular vein and common carotid artery are isolated
through a left mediolateral neck incision. Arterial blood
pressure (ABP) is measured continuously with a precalibrated
Millar transducer (model (MPC-500, Millar Instruments,
Houston, TX, U.S.A.) inserted into the carotid artery. The
jugular vein is cannulated for blood sampling during the
experiment. In addition, the femoral veins of both hindlegs
are cannulated for administration of test compound.
A left thoracotomy is performed at the fifth intercostal
space, and the heart is suspended in a pericardial cradle.
A 1- to 2-cm segment of the left circumflex coronary artery
(LCX) is isolated proximal to the first major diagonal
ventricular branch. A 26-gauge needle-tipped wire anodal
electrode (Teflon-coated, 30-gauge silverplated copper wire)
3-4 mm long is inserted into the LCX and placed in contact
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-34-
with the intimal surface of the artery (confirmed at the end
of the experiment). The stimulating circuit is completed by
placing the cathode in a subcutaneous (s.c.) site. An
adjustable plastic occluder is placed around the LCX, over
the region of the electrode. A precalibrated
electromagnetic flow probe (Carolina Medical Electronics,
King, NC, U.S.A.) is placed around the LCX proximal to the
anode for measurement of coronary blood flow (CBF). The
occluder is adjusted to produce a 40-50 percent inhibition
of the hyperemic blood flow response observed after 10-s
mechanical occlusion of the LCX. All hemodynamic and ECG
measurements are recorded and analyzed with a data
acquisition system (model M3000, Modular Instruments,
Malvern, PA. U.S.A.).
Thrombus Formation and Compound Administration Regimens
Electrolytic injury of the intima of the LCX is produced by
applying 100-~,A direct current (DC) to the anode. The
current is maintained for 60 min and then discontinued
whether the vessel has occluded or not. Thrombus formation
proceeds spontaneously until the LCX is totally occluded
(determined as zero CBF and an increase in the S-T segment).
Compound administration is started after the occluding
thrombus is allowed to age for 1 hour. A 2-hour infusion of
the compounds of the present invention at doses of 0.5 and 1
mg/kg/hour is begun simultaneously with an infusion of
thrombolytic agent (e. g. tissue plasminogen activator,
streptokinase, APSAC). Reperfusion is followed for 3 hour
after administration of test compound. Reocclusion of
coronary arteries after successful thrombolysis is defined
as zero CBF which persisted for 3 30 minutes.
Hematology and template bleeding time determinations
Whole blood cell counts, hemoglobin, and hematocrit values
are determined on a 40-~.L sample of citrated (3.8 percent)
blood (1 part citrate:9 parts blood) with a hematology
analyzer (Cell-Dyn 900, Sequoia-Turner. Mount View, CA,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-35-
U.S.A.). Gingival template bleeding times are determined
with a Simplate II bleeding time device (Organon Teknika
Durham, N.C., U.S.A.). The device is used to make 2
horizontal incisions in the gingiva of either the upper or
lower left jaw of the dog. Each incision is 3 mm wide x 2
mm deep. The incisions are made, and a stopwatch is used to
determine how long bleeding occurs. A cotton swab is used
to soak up the blood as it oozes from the incision.
Template bleeding time is the time from incision to stoppage
of bleeding. Bleeding times are taken just before
administration of test compound (0 min), 60 min into
infusion, at conclusion of administration of the test
compound (120 min), and at the end of the experiment.
All data are analyzed by one-way analysis of variance
(ANOVA) followed by Student-Neuman-Kuels post hoc t test to
determine the level of significance. Repeated-measures
ANOVA are used to determine significant differences between
time points during the experiments. Values are determined
to be statistically different at least at the level of
p<0.05. All values are mean ~ SEM. All studies are
conducted in accordance with the guiding principles of the
American Physiological Society. Further details regarding
the procedures are described in Jackson, et al., J.
Cardiovasc. Pharmacol., (1993), 21, 587-599.
The following Examples are provided to further
describe the invention and are not to be construed as
limitations thereof.
The abbreviations, symbols and terms used in the
examples have the following meanings.
Ac = acetyl
AIBN = azobisisobutyronitrile
Anal. - elemental analysis
Bn or Bzl - benzyl
Bu = butyl
n-BuLi = butyllithium
calcd = calculated
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-36-
DCC = dicyclohexylcarbodiimide
DIBAL -H = diisobutyl aluminum hydride
DMF = dimethylformamide
DMSO = dimethylsulfoxide
Et = ethyl
EtOAc = ethyl acetate
Et3N = triethylamine
Et20 = diethyl ether
EtOH = ethanol
EtSH = ethanethiol
FAB = Fast Atom Bombardment (Mass Spectroscopy)
FDMS = field desorption mass spectrum
Hex = hexanes
HOAt = 1-hydroxy-7-azabenzotriazole
HPLC = High Performance Liquid Chromatography
HRMS = high resolution mass spectrum
i-PrOH =
isopropanol
IR = Infrared Spectrum
LAH = lithium aluminum hydride
Me = methyl
MeI - methyl iodide
MeOH = methanol
MPLC = Medium Pressure Liquid Chromatography
NBS = N-bromosuccinimide
NMR = Nuclear Magnetic Resonance
Ph = phenyl
PPA = polyphosphoric acid
i-Pr = isopropyl
Rochelle's
Salt = potassium
sodium tartrate
RPHPLC =
Reversed
Phase High
Performance
Liquid
Chromatography
Si02 = silica gel
SM = starting material
TBS = tert-butyldimethylsilyl
TEA = triethylamine
Temp. - temperature
TFA = trifluoroacetic acid
CA 02287901 1999-10-29
WO 98/48?98 PCT/US98/08700
-37-
THF = tetrahydrofuran
TIPS = triisopropylsilyl
TLC = thin layer chromatography
triflic acid = trifluoromethanesulfonic acid
Unless otherwise stated, pH adjustments and work
up are with aqueous acid or base solutions. PrepLC
indicates preparative liquid chromatography using "Prep Pak
(TM)" silica cartridges; radial chromatography indicates
preparative chromatography using a "Chromatotron (TM)"
instrument.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-38-
Example 1
Preparation of 2- [4- [4-Methoxy-4-oxobutoxy]phenyl] -3- [4-
(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene.
0-
A. Methyl 4-(1-Pyrrolidinylmethyl)benzoate.
O~
O~ ~ \
Methyl 4-bromomethylbenzoate (5.43 g; 23.7 mmol) was
dissolved in 50 mL of THF. Pyrrolidine (5.0 mL; 2.5 eq) was
added, and the resultant mixture stirred at room temperature
for 2 h. Water was added and extraction carried out with
EtOAc (4 x 50 mL}. The combined organics were dried by
passage through Na2S04. The title compound was isolated by
flash chromatography on silica gel, eluting with EtOAc, as a
colorless liquid (4.77 g; 92%).
1H NMR (CDC13) 8 8.02 (d, J=7.7 Hz, 2H), 7.43 (d, J=7.7 Hz,
2H), 3.93 (s, 3H), 3.70 (s, 2H), 2.51 (br s, 4H), 1.80 (br
s, 4H). FDMS 219.2 (M).
B. 4-(2-Benzo[b]thiophenyl)phenyl Triisopropylsilyl Ether
\
--~OTips
S
In a flame-dried, argon-filled flask were combined
1.36 g (6.0 mmol) of 2-(4-hydroxyphenyl)benzo[b]thiophene
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-39-
and 1.68 mL (12.0 mmol) of Et3N in 10 mL of DMF. After
cooling in an ice-water bath, 3.23 g (12.0 mmol) of
triisopropylsilyl trifluorosulfonate was added. The bath was
removed, and stirring continued for 1 h while warming to
room temperature. The mixture was concentrated under
reduced pressure, and the title compound was isolated as a
white crystalline solid (2.05 g; 89% yield) by flash
chromatography on silica gel, eluting with
hexanes(95%)/EtOAc(5%).
Anal. calc'd for C23H3pOS: C, 72.19; H, 7.90. Found: C,
72.22; H, 7.91. FDMS 382.1 (M).
C. 2-(4-Triisopropylsilyloxyphenyl)benzo[b]thiophen-3-yl
4-(1-Pyrrolidinylmethyl)phenyl Ketone.
ps
Methyl 4-(1-pyrrolidinylmethyl)benzoate (2.Og;
9.12 mmol) was dissolved in 20 mL of a mixture of THF/MeOH/_
H20 (3:1:1). LiOH (0.46 g; 1.2 eq) was added, and the
resultant mixture stirred at room temperature for 3 days.
The mixture was neutralized with conc HC1, and the solvent
removed under reduced pressure. The crude 4-(1-pyrroli-
dinylmethyl)benzoic acid hydrochloride was dried in vacuo
for 2 h, and used without purification.
4-(1-Pyrrolidinylmethyl)benzoic acid hydrochloride was
dissolved in 15 mL of SOC12 with 3 drops of DMF and heated
under reflux for 2 h. After cooling, the excess SOC12 was
removed under reduced pressure. The crude 4-(1-pyrroli-
dinylmethyl)benzoyl chloride hydrochloride was dried in
vacuo overnight and used without purification.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-40-
4-(2-Benzo[b]thiophenyl)phenyl triisopropylsilyl ether
(part B) was dissolved in 1,2-dichloroethane (15 mL) in a
flame-dried, argon-filled flask and cooled in an ice-water
bath. 4-(1-Pyrrolidinylmethyl)benzoyl chloride
hydrochloride (0.44 g; 1.5 eq) was added. The flask was
covered with foil to minimize light exposure, and TiCl4
(0.48 mL; 4.0 eq) was added. The mixture was stirred
overnight, then poured into saturated NaHC03 (60 mL).
Extraction was carried out with EtOAc (4 x 50 mL), and the
combined organics were washed with brine and dried by
passage through Na2S04. The title compound was isolated
(0.22 g; 35o yield overall) as a viscous yellow oil by flash
chromatography on silica gel, eluting with EtOAc.
1H NMR (CDC13) 8 7.87 (m, 1H), 7.73 (m, 1H), 7.71 (d, J=8.1
Hz, 2H), 7.37 (m, 2H), 7.27 (m, 4H), 6.71 (d, J=6.8 Hz, 2H),
3.56 (s, 2H), 2.45 (br s, 4H), 1.77 (br s, 4H), 1.20 (m,
3H), 1.03 (d, J=7.0 Hz, 18H).
D. 2-(4-Hydroxyphenyl)-3-[4-(1-pyrrolidinylmethyl)benzyl]-
benzo [b] thiophene .
To the above silyl ether (part C) (0.22 g; 0.39 mmol)
in 5.0 mL of THF was added 15 mg (0.39 mmol) of LAH at 0 °C.
The bath was removed and the mixture was stirred for 1 h.
Hydrolysis was effected by addition of 1 drop of water, 1
drop of 5 N NaOH, and 3 drops of water, followed by stirring
for 1 h. The mixture was filtered and washed thoroughly
with THF, the filtrate was concentrated and the intermediate
carbinol was dried in vacuo for 25 min. The carbinol was
dissolved in methylene chloride (5.0 mL) under argon
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-41-
atmosphere and cooled in an ice-water bath. Triethylsilane
(0.43 mL; 2.70 mmol) was added, followed by dropwise
addition of 0.30 mL (3.86 mmol) of TFA. Upon completion of
addition of TFA, the bath was removed and stirring was
continued for 2 h. Saturated aqueous sodium bicarbonate (25
mL) was added, and extraction was carried out with EtOAc.
The combined organics were washed with brine and dried by
passage through sodium sulfate. Removal of the protecting
group was effected by treatment of the Tips derivative with
1.0 mL of TBAF (1 M in THF) in 3.0 mL of THF for 1 h. After
concentration under reduced pressure, the title compound (66
mg; 66% yield) was isolated by flash chromatography on
silica gel, eluting with a gradient of EtOAc(100-900)/-
Et3N(0-5%) /MeOH(0-5%) .
20
1H NMR (CDC13) 8 7.80 (d, J=8.1 Hz, 1H), 7.44 (d, J=8.1 Hz,
1H), 7.4-7.2 (m, 6H), 7.06 (d, J=6.8 Hz, 2H), 6.76 (d, J=6.8
Hz, 2H), 4.22 (s, 2H), 3.69 (s, 2H), 2.67 (br s, 4H), 1.86
(br s, 4H) . FDMS 400 (M+1) .
E. 2- [4- [4-Methoxy-4-oxobutoxy]phenyl] -3- [4- (1-pyrro-
lidinylmethyl ) benzyl] benzo [b] thiophene .
In an argon-filled flask were combined 66 mg (0.17
mmol) of the above phenol (Part D), Cs2C03 (0.38 g; 7 eq),
and methyl 4-chlorobutyrate (24 ~L; 1.2 eq) in 2.0 mL of
DMF. The resulting mixture was immersed in an oil bath
maintained at 75 °C for 2.5 h. After cooling, 25 mL of
water was added, and extraction was carried out with EtOAc
(4 x 25 mL). The combined organics were washed with brine
and dried by passage through Na2S04. The title compound
(52 mg; 63% yield) was isolated by flash chromatography on
silica gel, eluting with a gradient of EtOAc(100-
90%)/Et3N(0-5%)/MeOH(0-5o) .
1H NMR (CDC13) 7.86 (d, J=8.7, 1H), 7.52 (d, J=8.6, 1H),
8
7.44 (d, J=8.7, 2H), 7.30(m, 2), 7.24 (d, J=8.1, 2H), 7.12
(d, J=7.9, 2H), 6.94 (d, J=8.6, 2H), 4.27 (s, 2H), 4.04
(t,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-42-
J=6.0, 2H), 3.72 (s, 3), 3.59 (s, 2H), 2.55 (m, 6), 2.15 (m,
2H), 1.78 (m, 4H). FDMS 499.2 (M).
Example 2
Preparation of 2- [4- [4-Hydroxy-4-oxobutoxy] phenyl] -3- [4-
(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene Lithium Salt.
~7
\ O O
~S
Li
The ester of Example 1, Part E (47 mg; 94 ~mol) was
dissolved in 2 mL of a mixture of THF/MeOH/H20 (3:1:1) in an
argon atmosphere and 5 mg of LiOH (1.2 eq) was added. The
resulting mixture was stirred overnight then concentrated
under reduced pressure and dried in vacuo.
Example 3
Preparation of 2- [4- [4-Methoxy-4-oxobutoxy] phenyl] -3- [3-
methoxy-4-(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene.
o-
CA 02287901 1999-10-29
WO 98/48798 PCT/US98108700
-43-
A. Methyl 4-Bromomethyl-3-methoxybenzoate.
O
OMe
CH30
Br
Methyl 3-methoxy-4-methylbenzoate (9.95 g; 55.2 mmol)
and 10.81 g (60.7 mmol) of NBS were combined in 250 mL of
CC14 and heated to reflux. AIBN (0.75 g; 5.5 mmol) was
added, and the resultant mixture was heated at reflux for
8 h. The mixture was refrigerated, then filtered and
concentrated under reduced pressure. The residue was
triturated with hexanes and filtered to give the title
compound as white needles (11.7 g; 82% yield).
1H NMR (CDC13) 8 7.63 (d, J = 7.6 Hz, 1H), 7.58 (s, 1H),
7.41 (d, J = 7.9 Hz, 1H), 4.56 (s, 2H), 3.98 (s, 3H), 3.94
(s, 3H); FDMS 528 (M+).
B. Methyl 3-Methoxy-4-(1-pyrrolidinylmethyl)benzoate.
O
OMe
Ch-!~O
U
Methyl 4-bromomethyl-3-methoxybenzoate (1.0 g;
3.9 mmol) (Part A) was dissolved in THF (10 mL) and
pyrrolidine (1.3 mL; 15.4 mmol) was added at room
temperature. The mixture was stirred overnight at room
temperature, then poured into 50 mL of water. Extraction
was carried out with EtOAc (4 x 25 mL). The combined
organics were washed with brine and dried by passage through
sodium sulfate. The title compound was isolated (0.92 g;
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-44-
96o yield) by flash chromatography on silica gel, eluting
with EtOAc(100-95o)/Et3N(0-5o).
1H NMR (CDC13) b 7.62 (d, J = 7.8 Hz, 1H), 7.51 (s, 1H),
7.43 (d, J = 7.7 Hz, 1H), 3.90 (s, 3H), 3.87 (s, 3H), 3.69
(s, 2H), 2.57 (m, 4H), 1.79 (m, 4H).
C. 2-(4-Triisopropylsilyloxyphenyl)benzo[b]thiophen-3-yl
3-Methoxy-4-(1-pyrrolidinylmethyl)phenyl Ketone.
ps
Essentially following the procedure of Example Z,
Part C, the title compound was prepared from
4-{2-benzo[b]thiophenyl)phenyl triisopropylsilyl ether
(Example 1, Part B) and methyl 3-methoxy-4-(1-pyrrolidinyl-
methyl)benzoate (Part C) in 39% yield. Purification was
accomplished by flash chromatography on silica gel, eluting
with a gradient of EtOAc(100-95%)/Et3N(0-5o).
1H NMR (CDC13) 8 7.91 {m, 1H), 7.78 (m, 1H), 7.41 (m, 3H),
7.31 (m, 4), 6.75 (d, J=6.7, 2H), 3.81 (s, 3H), 3.63 (s,
2H), 2.54 (br s, 4H), 1.79 (br s, 4H), 1.22 (m, 3H), 1.08
(d, J=7.0, 18).
D. 2-(4-Hydroxyphenyl)-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl) benzyl] benzo [b] thiophene .
CA 02287901 1999-10-29
WO 98/48798 PCTIUS98/08700
-45-
To the above silyl ether (part C) (0.22 g; 0.37 mmol)
in 3.0 mL of THF was added 40 mg (0.37 mmol) of LAH at 0 °C.
The bath was removed and the mixture was stirred for 1 h.
Hydrolysis was effected by addition of 1 drop of water, 1
' 5 drop of 5 N NaOH, and 3 drops of water, followed by stirring
for 1 h. The mixture was filtered and washed thoroughly
with THF, the filtrate was concentrated, and the
intermediate carbinol was dried in vacuo for 25 min.
Removal of the TIPS protecting group was effected by
treatment with 1.0 mL of TBAF (1M in THF) in 3.0 mL of THF
for 1 h. The carbinol was then dissolved in methylene
chloride (3.0 mL) under argon atmosphere and cooled in an
ice-water bath. Triethylsilane (0.41 mL; 2.57 mmol) was
added, followed by dropwise addition of 0.28 mL (3.67 mmol)
of TFA. Upon completion of addition of TFA, the bath was
removed and stirring was continued for 2 h. Saturated
aqueous sodium bicarbonate (25 mL) was added, and extraction
was carried out with EtOAc. The combined organics were
washed with brine and dried by passage through sodium
sulfate. After concentration under reduced pressure the
title compound (66 mg; 65% yield) was isolated by flash
chromatography on silica gel eluting with a gradient of
EtOAc(100-90a)/Et3N(0-5%)/MeOH(0-5%).
1H NMR (CDC13) 8 7.85 (m, 1H), 7.56 (m, 1H), 7.32 (m, 4H),
7.19 (d, J=7.6, 1H), 6.73 (m, 3H), 6.63 (s, 1H), 4.26 (s,
2H), 3.73 (s, 2H), 3.58 (s, 3H), 2.69 (br s, 4H), 1.85 (br
s, 4H). FDMS 430 (M+1).
E. 2- [4- [4-Methoxy-4-oxobutoxy]phenyl] -3- [3-methoxy-4-
(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene.
By following essentially the procedure of Example 1-E,
the title compound was prepared from the above phenol (Part
D) and methyl 4-chlorobutyrate in 85o yield. Purification
was effected by flash chromatography on silica gel, eluting
with a gradient of EtOAc(100-94o)/Et3N(0-5%)/MeOH(0-2o).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-46-
1H NMR (CDC13) 8 7.88 (d, J--8.5 Hz, 1H), 7.58 (d, J=8.9 Hz,
1H), 7.48 {d, J=8.6 Hz, 2H), 7.35-7.30 (m, 2), 7.23 (d,
J=7.6 Hz, 1H), 6.96 {d, J=8.6 Hz, 2H), 6.74 {d, J=7.9 Hz,
1H), 6.71 (s, 1H), 4.29 (s, 2H), 4.08 (t, J=6.1 Hz, 2H),
3.74 (s, 6H), 3.65 (s, 2H), 2.59 (m, 6H), 2.18 (m, 2H), 1.82
(br s, 4H) . FDMS 529.3 (M) .
Example 4
Preparation of 2- [4- [4-Hydroxy-4-oxobutoxy]phenyl] -3- (3-
methoxy-4-(1-pyrrolidinylmethyl)benzyl]benzo(b]thiophene.
H
The ester of Example 3 (24 mg; 45 ~,mol) was combined
with 2.0 mL of 3 M HC1 and heated in an oil bath maintained
at 90 °C overnight. The mixture was concentrated under
reduced pressure and dried in vacuo to give 23 mg (920
yield) of the title compound.
1H NMR (DMSO-d6) 8 10.05 (br s, 1H), 7.98 (m, 1H), 7.66 (m,
1H), 7.48 (d, J=8.5, 2H), 7.35 (m, 3H), 7.07 (d, J=8.6, 2H),
6.94 (s, 1H), 6.65 {d, J=7.8, 1H), 4.30 (s, 2H), 4.20 (d,
J--5.14, 2H), 4.05 (t, J=6.4, 2H), 3.76 (s, 3H), 3.35 (br s,
2H), 3.03 (br s, 2H), 2.41 (t, J=7.4, 2H), 2.0-1.8 (m, 6H).
FDMS 516 (M for free base) .
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-47-
Example 5
Preparation of 2- [4- [4-Hydroxy-4-oxobutoxy] phenyl] -
3-[3-methoxy-4-(2-oxopyrrolidin-1-ylmethyl)benzyl]-
benzo [b] thiophene .
The ester of Example 3 (45 mg; 85 ~mol) was dissolved
in 0.5 mL of CH2C12 and 9 mg (1 eq) of BrCN was added.
After stirring for 5 min at room temperature, 25 mL of EtOAc
was added. The organics were washed with saturated Na2C03,
and dried by passage through Na2S04. The mixture was
concentrated under reduced pressure, placed under high
vacuum for 1 h and dissolved in 1 mL of THF. In a separate
argon-filled flask, 6 mg of NaH (60% in mineral oil) was
suspended in anhydrous THF. After stirring for 10 min,
2-pyrrolidinone (32 ~,L; 0.42 mmol) was added, and stirring
was continued for 0.5 h. The THF solution of the
benzothiophene prepared above was added and the mixture
immersed in an oil bath maintained at 70 °C for 1 h, then
stirred while cooling to room temperature overnight. EtOAc
(70 mL) was added, and the resulting solution washed with
saturated NaHC03. No product was found in the organic
layer. The aqueous portion was acidified with conc HC1 and
extracted with EtOAc (3 x 80 mL). The combined organics
were washed with brine and dried by passage through Na2S04.
The title compound (10 mg; 22% yield) was isolated by flash
chromatography on silica gel, eluting with a gradient of
EtOAc (100-98%) /HOAc (0-2 0 ) .
1H NMR (CDC13) 8 7.88 (m, 1H), 7.59 (m, 1H), 7.44 (d, J=8.6,
2H), 7.35 (m, 2H), 7.04 (d, J=7.4, 1H), 6.95 (d, J=8.7, 2H),
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-48-
6.70 (d, J=8.4, 1H), 6.68 (s, 1H), 4.47 (s, 2H), 4.27 (s,
2H), 4.10(t, J=6.0, 2H), 3.72(s, 3H), 3.32 (t, J=7.0, 2H),
2.61 (t, J=7.0, 2H), 2.46 (t, J=8.1, 2H), 2.17 (m, 2H), 2.03
(m, 2H); FDMS 528.82 (M).
Example 6
Preparation of 2- [4- [4-Methoxy-4-oxobutoxy] phenyl] -3- [3-
methoxy-4-[3-(1-oxoethyl)imidazolidin-1-ylmethyl]benzyl]-
benzo[b]thiophene Oxalate.
The ester of Example 3 (45 mg; 85 ~mol) was dissolved
in 0.5 mL of CH2C12 and 9 mg (1 eq) of BrCN was added.
After stirring for 5 min at room temperature, 25 mL of EtOAc
was added. The organics were washed with saturated Na2C03
and dried by passage through Na2S04. The mixture was
concentrated under reduced pressure, placed under high
vacuum for 1 h and dissolved in 1 mL of THF. Following
addition of 143 mg (2.5 eq) of 1-acetylimidizolidine
[Butula, Ivan. Juatus Liebigs Ann. Chem., 718, 260-3
(1968)], the mixture was stirred at room temperature
overnight. Saturated NaHC03 (25 mL) was added, and
extraction was carried out with EtOAc (4 x 25 mL). The
combined organics were dried by passage through Na2S04. The
title compound (0.15 g; 53o yield) was purified by flash
chromatography on silica gel eluting with a gradient of
EtOAc(100-90%)/Et3N(0-5o)/MeOH(0-5o).
Anal. calc'd for C33H36N205S'C2H204: C, 63.43; H, 5.78; N,
4.23. Found: C, 63.15; H, 5.85; N, 4.05. FDMS 572.2 (M).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98f08700
-49-
Example 7
Preparation of 2- [4- [4-Hydroxy-4-oxobutoxy]phenyl] -3- [3-
methoxy-4-[3-(1-oxoethyl)imidazolidin-1-ylmethyl]benzyl]-
' 5 benzo [b] thiophene .
o\
o
' OH
\ / \
O
S
The title compound was prepared from the above ester
(Example 6) essentially by the method of Example 14 in 930
l0 yield.
1H NMR (MeOH-d4) 8 7.84 (d, J=7.4 Hz, 1H), 7.59 (d, J=7.5
Hz, 1H), 7.43 (d, J=8.6 Hz, 2H), 7.30 (m, 3H), 7.00 (d,
J=7.0 Hz, 2H), 6.89 (s, 1H), 6.79 (d, J=7.5 Hz, 1H), 4.36
15 (s, 2H), 4.33 (s, 2H), 4.07 (t, J=5.1, 2H), 3.87 (m, 2H),
3.80 (s, 3H), 3.74 (m, 2H), 3.31 (s, 2H), 2.52 (t, J=7.4,
2H), 2.08 (m, 5H); FABMS 559.3 (M+1 for free base).
Example 8
20 Preparation of 3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] -2-
[4-(4-methoxy-4-oxobutoxy)phenyl]benzo[b]thiophene.
0
\ / ~o
/ \ o /
s
A. 2-(4-Methoxyphenyl)benzo[b]thiophen-3-yl
25 4-[2-(1-Pyrrolidinyl)ethoxy]phenyl Ketone.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-50-
O / O
\ / \ o
i S \
Sodium hydride (0.69 g of 60% NaH in mineral oil;
17.22 mmol) was suspended in 15 mL of dry DMF in a flame-
s dried, argon-filled flask. After stirring for 15 min, a
solution of 4-(1-pyrrolidinyl)ethanol was added. After
stirring for 15 min and gas evolution had ceased,
4-fluorophenyl 2-(4-methoxyphenyl)benzo[b]thiophen-3-yl
ketone [prepared by acylation of 2-(4-methoxyphenyl)-
benzo[b]thiophene with 4-fluorobenzoyl chloride] (5.2 g;
14.34 mmol) in 15 mL of dry DMF was added. The mixture was
stirred at room temperature for 5 h, then poured into 25 mL
of water. Extraction was carried out with EtOAc (4 x
25 mL). The combined organics were washed with brine and
dried by passage through sodium sulfate. The title compound
(5.12 g; 78% yield) was isolated as a colorless oil by flash
chromatography on silica gel, eluting with a gradient of
EtOAc (100-85%) /Et3N(0-5%) /MeOH(0-10%) .
1NMR (CDC13) 7.85 (m, 1H) , 7.76 (d, J=6.3,2H) , 7.63 (m,
b
1H), 7.36 (m, 4H), 6.77(d, J=7.2, 4H), 4.22 (t, J=5.3, 2H),
3.75 (s, 3H), 3.04 (t, J=5.2, 2H),2.83 (br s, 4H), 1.90 (br
s, 4H); FDMS 457 (M).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-51-
8. 2- (4-Methoxyphenyl) -3- [4- [2- (1-pyrrolidinyl) ethoxy] -
benzyl] benzo [b] thiophene.
O
\ / \
0
i s
To the above ketone (Part A) (3.12 g; 11.2 mmol) in
40.0 mL of THF was added 0.42 g (11.2 mmol) of LAH at 0 °C.
The bath was removed and the mixture was stirred for 1 h.
Hydrolysis was effected by addition of 0.42 mL of water,
0.42 mL of 5N NaOH, and 1.26 mL of water, followed by
stirring for 1 h. After the mixture was filtered and washed
with THF, the filtrate was concentrated; and the
intermediate carbinol was dried in vacuo for 25 min. The
carbinol was dissolved in methylene chloride (40.0 mL) under
argon atmosphere and cooled in an ice-water bath.
Triethylsilane (12.5 mL; 78.3 mmol) was added, followed by
dropwise addition of 8.6 mL (112.0 mmol) of TFA. Upon
completion of addition of TFA, the bath was removed and
stirring was continued for 2 h. Saturated aqueous sodium
bicarbonate (50 mL) was added, and extraction was carried
out with EtOAc. The combined organics were washed with
brine and dried by passage through sodium sulfate. The
title compound (4.45 g; 90% yield) was isolated as a
colorless oil by flash chromatography on silica gel, eluting
with a gradient of EtOAc(100-95%)/Et3N(0-5%).
1NMR (CDC13) 8 7.87 (m, 1H), 7.77 (d, J=6.4, 2H), 7.65 (m,
1H), 7.34 (m, 4H), 6.78 (d, J=7.4, 4H), 4.20 (s, 2H), 4.15
(t, J=5.3, 2H), 3.73 (s, 3H), 3.14 (t, J=5.4, 2H), 2.91 (br
s, 4H), 1.90 (br s, 4H); FDMS 444 (M+1).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-52-
C. 2- (4-Hydroxyphenyl) -3- [4- [2- (1-pyrrolidinyl) ethoxy] -
benzyl] benzo [b] thiophene .
o
\ / \
OH
S
The above methyl ether (4.5 g; 10.1 mmol) {Part B) was
dissolved in 45 mL of dichloroethane under an argon
atmosphere and cooled in an ice-water bath. To this was
added ethanethiol (6.0 mL; 81.1 mmol) and 5.41 g {40.6 mmol)
of aluminum chloride, and the mixture was stirred in the
cold bath for 1 h. Saturated NaHC03 was added, and stirring
was continued while warming to room temperature for 1 h.
The title compound (0.23 g; 74o yield) was isolated by
filtration and washed with water.
1NMR (CDC13) 8 7.83 (m, 1H), 7.47 (m, 1H), 7.29 (m, 2H),
6.98 (d, J=8.5, 2H), 6.83 (m, 4H), 6.69 (d, J=8.6, 2H), 4.15
(m, 4H), 3.05 {m, 2), 2.85 (br s, 4H), 1.91 (br s, 4H); FDMS
430 (M+1) .
D. 3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] -2- (4- (4-methoxy-
4-oxobutoxy)phenyl]benzo[b]thiophene.
By following essentially the procedure of Example 1-E
the title compound was prepared from the above phenol (Part
D) and methyl 4-chlorobutyrate in 83o yield. Purification
was effected by flash chromatography on silica gel, eluting
with a gradient of EtOAc (100-94°s) /Et3N{0-5%) /MeOH(0-2o) .
1NMR (CDC13) b 7.84 (d, J=6.8, 1H), 7.52 (d, J=8.2, 1H),
7.43 (d, J=8.3, 2H), 7.30 (m, 2H), 7.07 {d, J=8.1, 2H), 6.93
(d, J=8.2, 2H), 6.83 (d, J=8.2, 2H), 4.22 (br s, 4H), 4.05
(t, J=5.6, 2H), 3.73 (s, 3H), 3.08 (br s, 2H), 2.88 (br s,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-53-
4H), 2.56 (t, J=7.2, 2H), 2.15 (m, 2H), 1.93 (br s, 4H).
FDMS 529.2 (M) .
Example 9
Preparation of 2- [4- (4-Hydroxybutoxy)phenyl] -3- [4- [2
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
H
The ester of Example 8 (0.39 g; 0.74 mmol) was
dissolved in THF and r-AU (28 mg; 0.74 mmol) was added. The
resultant mixture was stirred for 2 h. Workup was effected
by addition of 2 drops of water, 2 drops of 5 N NaOH, and 6
drops of water. After stirring for 1 h, the mixture was
filtered and washed with fresh THF. The title compound
(0.22 g, 60% yield) was isolated by flash chromatography,
eluting with a gradient of EtOAc(100-90%)/Et3N(0-5%)/MeOH(0-
5%) .
1NMR (CDC13) 8 7.88 (m, 1H), 7.43 (m, 5H), 7.09 (d, J=8.4,
2H), 6.96 (d, J=8.6, 2H), 6.84 (d, J=8.5, 2H), 4.34 (t,
J=4.9, 2H), 4.24 (s, 2H), 4.08 (t, J=6.0, 2H), 3.77 (t,
J=5.6, 2H), 3.24 (br s, 2H), 3.08 (br s, 4H), 2.04 (br s,
4H}, 1.95 (m, 2H), 1.81 (m, 2H). FDMS 501.02 (M).
Example 10
Preparation of 6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl] -2- [4- [2-methoxy-2-oxoethoxylphenyl] -
benzo [b] thiophene.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-54-
~O
N
\ /
OMe
HO
O
A suspension of 6-benzyloxy-2-(4-hydroxyphenyl)-3-[3-
methoxy-4-(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene
(100 mg) and cesium carbonate (330 mg) in DMF (2.0 mL) was
treated with methyl bromoacetate (20 ~,L) and allowed to stir
at ambient temperature under nitrogen for 1 h. The reaction
mixture was diluted with brine(50 mL) and extracted with
EtOAc (30 mL x 3). The combined organic layers were dried
with sodium sulfate and concentrated under reduced pressure.
The residue was dissolved in THF (4.0 mL) and treated
sequentially with a solution of ammonium formate (25% in
H20, 2.0 mL) and 10% palladium on carbon (100 mg) at ambient
temperature. The resulting mixture was stirred at ambient
temperature under argon for 1.5 h before it was filtered
through diatomaceous earth followed by rinsing with
dichloromethane and methanol. The filtrate was extracted
with dichloromethane (20 mL x 3) from water (30 mL). The
combined organic layers were dried with sodium sulfate and
concentrated under reduced pressure. Chromatography with
Et3N:MeOH:EtOAc (5:5:90) afforded the product (72 mg).
FDMS m/e: found 518(M+H+); 1H NMR(CDC13): 87.37(d,2H),
7.15(d,lH), 7.13(d,lH), 7.08(s, 1H), 6.90(d,2H), 6.60(d,lH},
6.59(s,lH}, 6.31(d, 1H), 4.65(s,2H), 4.17(s, 2H),
3.82(s,3H), 3.70(s,2H), 3.47(s,3H), 2.68(m,4H), 1.81 (m,4H).
The 6-benzyloxy-2-(4-hydroxyphenyl)-3-[3-methoxy-4-[(1-
pyrrolidinyl)methyl] benzyl] benzo [b] thiophene may be obtained
using similar procedures to the following.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-55-
A. a-(4-Benzyloxyphenyl)-a-hydroxy-N,N-dimethyl-
thioacetamide.
' OH
\ N \
Bn0
To a solution of distilled diisopropylamine (22.9 mL,
175 mmol) in 400 mL of anhydrous THF at -78 °C was added
1.6 M n-butyllithium in hexanes (100 mL, 160 mmol) over a
period of 45 min. The mixture was stirred at -78 °C for
1.5 h. To the solution was cannulated over a period of 1 h
a solution of 4-benzyloxybenzaldehyde (30.9 g, 146 mmol) and
N,N-dimethylthioformamide (13.7 mL, 160 mmol) in 100 mL of
distilled THF. The reaction mixture was stirred at -78 °C
for 16 h. The reaction was then quenched with 500 mL of
saturated NH4C1 solution. The mixture was extracted with
EtOAc (3 x 1 L), and the combined organic layers were dried
over MgS04 and concentrated under reduced pressure. The
residue was then recrystallyzed from EtOAc/hexanes to afford
20.0 g (66.5 mmol, 460) of an off-white solid.
mp 104-107 °C; FDMS 301 (M+); Anal. Calcd for C17H19N02S:
C, 67.75; H, 6.35; N, 4.65. Found: C, 67.61; H, 6.37; N,
4.57.
B. 6-Benzyloxy-2-(dimethylamino)benzo(b]thiophene.
\ N/
Bn0
To a solution of the above thioacetamide (Part A)
(500 mg, 1.66 mmol) in 65 mL of dry dichloroethane at room
temperature was added dropwise methanesulfonic acid
(0.54 ml, 8.3 mmol). The red reaction mixture was stirred
for 1.5 h and then poured into 10 mL of saturated aqueous
NaHC03 solution, followed by addition of 3 mL of H20, and
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-56-
stirred vigorously. The layers were separated and the
organic layer was dried over MgS04 and concentrated under
reduced pressure. The residue was then purified by flash
chromatography (silica gel, 10% Et20/hexanes) to afford
327 mg (1.15 mmol, 70%) of a white solid.
mp 78-81 °C; FDMS 283 (M+); Anal. Calcd for C17H17NOS: C,
72.05; H, 6.05; N, 4.94. Found: C, 72.22; H, 6.15; N,
4.89.
C. 6-Benzyloxy-2-(dimethylamino)benzo[b]thiophen-3-yl
3-Methoxy-4-(1-pyrrolidinylmethyl)phenyl Ketone.
O
7
V
A solution of 6-benzyloxy-2-(dimethylamino)benzo[b]-
thiophene (2.5 g, 8.8 mmol) and 3-methoxy-4-(1-pyrrolidinyl-
methyl)benzoyl chloride hydrochloride (3.0 g, 1.3 equiv) in
chlorobenzene (30 mL) was heated at 135 °C under nitrogen
for 2 h. The cooled reaction mixture was diluted with brine
(100 mL), neutralized with NaOH solution (5.0 M), and
extracted with dichloromethane (100 mL x 3). The combined
organic layers were dried with sodium sulfate and
concentrated under reduced pressure. Chromatography with
Et3N:EtOAc (5:95) afforded the product as a brown oil
( 3 . 7 g, 84 0 ) .
1H NMR (CDC13): 8 7.5-6.9 (m, 11H), 5.10 (s, 2H), 3.90 (s,
3H), 3.71 (s, 2H), 2.91 (s, 6H), 2.60 (m, 4H), 1.83 (m, 4H):
FDMS m/e: 500.0 (M+).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-57-
D. 4-Bromophenyl Triisopropylsilyl Ether.
Br
OTIPS
To 4-bromophenol (6.1 g, 35 mmol) and imidazole (2.6 g)
in DMF (30 mL) at ambient temperature was added slowly
triisopropylsilyl trifluoromethanesulfonate (10.5 mL) while
stirring. The resulting mixture was stirred at ambient
temperature for 1 h before dilution with water (200 mL) and
extraction with EtOAc (100 mL x 3). The combined organic
layers were dried with sodium sulfate and concentrated under
reduced pressure. Chromatography with EtOAc-hexanes (0-5%
gradient elusion) afforded the product as a colorless oil
(11.2 g, 96%).
1H NMR (CDC13): 8 7.32 (d, J=9.1 Hz, 2H), 6.77 (d, J=9.1 Hz,
2H), 1.23 (m, 3H), 1.10 (d, J=7.0 Hz, 18H); FDMS m/e: 330
( M+H+ ) .
E. 6-Benzyloxy-2-[4-hydroxyphenyl]benzo[b]thiophen-3-yl
3-Methoxy-4-(1-pyrrolidinylmethyl)phenyl Ketone.
0
s
2 0 off
Magnesium turnings (0.24 g) were placed in a two-neck
100 mL round-bottom flask fitted with a reflux condenser and
a magnetic stir bar. The whole apparatus was flame-dried
and allowed to cool to ambient temperature. Dry THF (17 mL)
and a small crystal of iodine were then introduced followed
by slow addition of 4-bromophenyl triisopropylsilyl ether
CA 02287901 1999-10-29
WO 98/48798 PCT/LTS98/08700
-58-
{3.5 g) while stirring at ambient temperature. The reaction
mixture was warmed to a gentle reflux for 1 h or until the
magnesium turnings were completely consumed to give a 0.5 M
solution of the Grignard reagent. This freshly prepared
Grignard solution (15 mL) was added slowly to a stirring
solution of 6-benzyloxy-2-(dimethylamino)benzo[b]thiophen-
3-yl 3-methoxy-4-(1-pyrrolidinylmethyl)phenyl ketone (2.5 g,
5.0 mmol) in THF (15.0 mL) at 0 °C under argon. The mixture
was stirred at 0 °C for 2 h before quenching with saturated
aqueous NH4C1 solution (50 mL) and extraction with CH2CI2
(50 mL x 3). The combined organic layers were dried with
sodium sulfate and concentrated under reduced pressure.
Chromatography with EtOAc afforded a oily brown material as
the major fraction. This material was dissolved in THF
(25 mL), treated with a solution of tetrabutylammonium
fluoride (1.0 M in THF, 6 mL) at ambient temperature for
1 h, and then concentrated under reduced pressure.
Chromatography with Et3N:MeOH:EtOAc (5:10:85) afforded the
title compound as a yellow foam (2.75 g, 100%).
1H NMR (CDC13): 8 7.75 {d, 1H), 7.52-7.30 (m, 6H), 7.20 (d,
2H), 7.20-7.08 (m, 4H), 6.60 (d, 2H), 5.18 (s, 2H), 3.70 (s,
5H), 2.68 (m, 4H), 1.85 (m, 4H).
F. 6-Benzyloxy-2-(4-hydroxyphenyl)-3-[3-methoxy-4
(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene.
v
0
N
J
y
I
sno ~ s
/ ' OH
6-Benzyloxy-2-{4-hydroxyphenyl)benzo[b]thiophen-3-yl
3-methoxy-4-(1-pyrrolidinylmethyl)phenyl ketone (2.75 g, 5.0
mmol) in THF (25 mL) was treated with lithium aluminum
hydride (420 mg) at 0 °C for 2 h, then quenched with water
(1 mL) and sodium hydroxide (1.0 M, 3 mL). Stirring was
CA 02287901 1999-10-29
WO 98/48798 PCT/US98108700
-59-
continued for 45 min. The reaction mixture was diluted with
brine (100 mL) and extracted with dichloromethane (100 mL x
3). The combined organic layers were dried with sodium
sulfate and concentrated in vacuo to give a white foam-like
material. This material was dissolved in dichloromethane
(50 mL), treated with triethylsilane (6.0 mL) and
trifluroacetic acid (5.0 mL) at 0 °C for 2 h, and
concentrated under reduced pressure. The residue was
extracted with dichloromethane (100 mL x 3) which was washed
with saturated aqueous sodium bicarbonate (100 mL). The
combined organic layers were dried with sodium sulfate and
concentrated. Chromatography with Et3N:MeOH:EtOAc (5:5:90)
afforded the product as a white solid (2.1 g, 78%).
1H NMR (CDC13): b 7.50-7.27 (m, 9H), 7.15 (d, 1H), 6.96 (d,
1H), 6.69 (d, 2H), 6.65 (d, 1H), 6.55 (s, 1H), 5.12 (s, 2H),
4.18 (s, 2H), 3.71 (s, 2H), 3.57 (s, 3H), 2.70 (m, 4H), 1.83
(m, 4H); FDMS m/e: 536 (M+H+).
Example 11
Preparation of 6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl] -2- [4- [2-hydroxyethoxy]phenyl] -
benzo [b] thiophene .
v
O N
% ~ ~ -O
HO
OH
To 6-hydroxy-2-[4-(2-methoxy-2-oxoethoxy)phenyl]-3-[3-
methoxy-4-(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene (36
mg) in THF (2 mL) was added lithium aluminum hydride (16 mg)
and the mixture was stirred under argon at ambient
temperature for 1 h. The reaction was quenched with water
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-60-
(1 mL) and sodium hydroxide solution (1.0 M, 1 mL) while
stirring continued for 30 min. The mixture was then diluted
with brine (50 mL) and extracted with dichloromethane
(30 mL x 3). The combined organic layers were dried with
sodium sulfate and concentrated in vacuo. Chromatography
with Et3N:MeOH:EtOAc (5:10:85) afforded the product (29 mg).
FDMS m/e: found 490(M+H+); 1H NMR(CD30D): b 7.38(d,2H),
7.35(d,lH), 7.19(s,lH), 7.18(d, 1H), 6.97(d,2H), 6.80(s,lH),
6.77(d,lH), 6.71(d, 1H), 4.21(s,2H), 4.05(t, 2H),
4 . 03 (s, 2H) , 3 . 87 (t, 2H) , 3 . 73 (s, 3H) , 3 . 02 (m, 4H) , 1 . 94 (m,
4H) .
Example 12
Preparation of 6-Hydroxy-2-[4-{2-hydroxy-2-oxoethoxy]-
phenyl)-3-[3-methoxy-4-(1-pyrrolidinylmethyl)benzyl]-
benzo [b] thiophene .
N
J
O
HO
OH
The title compound was prepared from the ester of
Example 10 by using the same procedure employed for the
preparation of Example 14.
1H NMR(CDC13): 8 7.38(m,2H), 7.20(m,2H), 6.96(m,2H), 6.82(m,
4H), 4.26(s,2H), 4.25(s, 2H), 3.78(s,3H), 3.76(s,2H),
3.19(m, 4H), 2.06 (m,4H).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-61-
Example 23
Preparation of 6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl) benzyl] -2- [4- [4-methoxy-4-oxobutoxy] phenyl] -
benzo [b] thiophene.
HO
OMe
A. 6-Benzyloxy-3-[3-methoxy-4-(1-pyrrolidinylmethyl)-
benzyl] -2- [4- [4-methoxy-4-oxobutoxy] phenyl] -
benzo [b] thiophene .
Bn0
OMe
A suspension of 6-benzyloxy-2-(4-hydroxyphenyl)-3-[3-
methoxy-4-(1-pyrrolidinylmethyl)benzyl]benzo[b]thiophene
(161 mg) and cesium carbonate (700 mg) in DMF (2.0 mL) was
treated with methyl 4-chlorobutyrate (45 ~.L) and allowed to
stir at 90 °C under nitrogen for 3 h. The reaction mixture
was diluted with water (50 mL), neutralized with dilute
hydrochloric acid and extracted with EtOAc (30 mL x 3). The
combined organic layers were dried with sodium sulfate and
concentrated under reduced pressure. Chromatography with
Et3N-EtOAc (0-5%) afforded the product.
~o 0
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-62-
1H NMR(CDC13): 8 7.48-7.34(m,9H), 7.20(d,lH), 7.00(d,lH),
6.91(d, 2H), 6.70(d,lH), 6.67(s,lH), 5.13(s,2H), 4.21(s,
2H) , 4 . 04 (t, 2H) , 3 . 71 (s, 3H) , 3 . 62 (s, 2H) , 2 . 56 (m, 6H) ,
2.14(m,2H), 1.78(m,4H).
B. 6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinylmethyl)benzyl]-
2- [4- [4-methoxy-4-oxobutoxy]phenyl]benzo [b] thiophene.
6-Benzyloxy-3-[3-methoxy-4-(1-pyrrolidinylmethyl)-
benzyl] -2- [4- (4-methoxy-4-oxobutoxy) phenyl] benzo [b] thiophene
(147 mg) in THF (3.0 mL) was treated sequentially with a
solution of ammonium formate (25% in H20, 2.0 mL) and 10%
palladium on carbon (100 mg) at ambient temperature. The
resulting mixture was stirred at ambient temperature under
argon for 3 h before it was filtered through diatonaceous
earth followed by rinsing with dichloromethane and methanol.
The filtrate was extracted with dichloromethane (20 mL x 3)
from water (30 mL). The combined organic layers were dried
with sodium sulfate and concentrated under reduced pressure.
Chromatography with Et3N:EtOAc (0-5%) afforded the product
(108 mg).
1H NMR(CDC13): 8 7.37(d,2H), 7.15(d,lH), 7.14(d,lH), 7.10(s,
1H), 6.88(d,2H), 6.64(d,lH), 6.60(s,lH), 6.28(d,lH), 4.17(s,
2H) , 4 . 02 (t, 2H) , 3 . 70 (s, 3H) , 3 .46 (s, 2H) , 2 . 67 (m, 4H) ,
2 . 54 (t, 2H) , 2 .12 (m, 2H) , 1. 81 (m, 4H) .
Example 14
Preparation of 6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl] -2- [4- [4-hydroxy-4-oxobutoxy]phenyl] -
3 0 benzo [b3 thiophene .
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-63-
HO
OH
6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinylmethyl)benzyl]-
2 - [4 - [4 -methoxy-4 -oxobutoxy] phenyl ] benzo [b] thiophene ( 14 7
mg) was dissolved in THF:MeOH:H20 (3:1:1, 3.0 mL), treated
with lithium hydroxide monhydrate (12 mg) in one portion,
and allowed to stir at ambient temperature for 4 days. The
reaction mixture was neutralized with dilute HC1 and
concentrated in vacuo. The residue was dissolved in
methanol. The solution was transfered to a clean vial and
solvent was removed with a stream of nitrogen to give the
product as an off-white solid. (100 mg).
FDMS m/e: found 532(M+H+); 1H NMR(CD30D): 8 7.37(d,4H),
7.25(d,lH), 7.20(s,lH), 6.93(d, 2H), 6.81(s,lH), 6.80{d,lH),
6.71(d,lH), 4.23(s, 2H), 4.20(s, 2H), 4.00(t,2H), 3.72(s,
3H) , 3 .23 (m, 4H) , 2 .42 (t, 2H) , 2 . 02 (m, 6H) .
Example 15
Preparation of 5-Hydroxy-3- [4- [2- (1-pyrrolidinyl) ethoxy] -
benzyl] -2- [4- (3-carboxypropyloxy)phenyl]benzo [b] thiophene
Hydrochloride.
O~N
V
Hci
HO
O'~CO ZH
A. 6-Benzyloxy-2-dimethylaminobenzo[b]thiophene-3-yl
4- [2- (1-Pyrrolidinyl) ethoxy] phenyl Ketone.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-64-
0
O~N
BzlO I ~ S NMe 2
By essentially following the procedure described in
Example 10-C, the title compound was prepared as an oil
starting from 6-benzyloxy-2-dimethylaminobenzo[b]thiophene
and 4-[2-(1-pyrrolidinyl)ethoxy]benzoyl chloride hydro-
chloride in 38% yield following MPLC (Si02; 15% then 20%
then 30% THF with 5% TEA in hexanes).
FDMS 500 (M+); Anal. calcd for C3pH32N203S: C, 71.97; H,
6.44; N, 5.60. Found: C, 72.18; H, 6.29; N, 5.53.
B. 6-Benzyloxy-2-(4-triisopropylsilyloxyphenyl)-
benzo [b] thiophene-3-yl 4- [2- (1-Pyrrolidinyl) ethoxy] phenyl
Ketone.
~ N
BZIO
PS
By essentially following the procedure described in
Example 10-E, the title compound was prepared as an oil
starting from 6-benzyloxy-2-dimethylaminobenzo[b]thiophene-
3-yl 4-[2-(1-pyrrolidinyl)ethoxy]phenyl ketone (Part A) and
1-bromo-4-(triisopropylsilyloxy)benzene in 57% yield
following MPLC (Si02; 10% then 15% then 20% THF with 5o TEA
in hexanes).
FDMS 706 (M+); Anal. calcd for C43H51N04S: C, 74.63; H,
7.72; N, 2.02. Found: C, 74.43; H, 7.59; N, 2.10.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-65-
C. 6-Benzyloxy-2-(4-hydroxyphenyl)benzo[b]thiophene-3-yl
4- [2- (1-Pyrrolidinyl) ethoxy] phenyl Ketone.
O N
~ O~
I \ ~
BziO
OH
By essentially following the procedure described in
Example 10-E, the title compound was prepared as a foam
starting from 6-benzyloxy-2-(4-triisopropylsilyloxyphenyl)-
benzo[b]thiophene-3-yl 4-[2-(1-pyrrolidinyl)ethoxy]phenyl
ketone (Part B) in quantitative yield following MPLC (Si02;
0.5o in CHC13 sat'd with NH40H).
FDMS 550 (M+1) .
D. 6-Benzyloxy-2-(4-hydroxyphenyl)-3-[4-[2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
O~N
\ ~
BZIO ~ ~
v _OH
By essentially following the procedure described below
in Example 25, Part B, the title compound was prepared as a
foam starting from 6-benzyloxy-2-(4-hydroxyphenyl)-
benzo[b]thiophene-3-yl 4-[2-(1-pyrrolidinyl)ethoxy]phenyl
ketone (Part C) in 52% yield following MPLC (Si02; 0.5% in
CHC13 sat'd with NH40H).
FDMS 536 (M+1); Anal, calcd for C34H33NO3S: C, 76.23; H,
6.21; N, 2.62. Found: C, 76.45; H, 6.09; N, 2.91.
E. 6-Benzyloxy-3-[4-[2-(1-pyrrolidinyl)ethoxy]benzyl]-2-
[4- ( 3 -cyanopropyloxy) phenyl] benzo [b] thiophene .
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-66-
O~N
BzlO
O~CN
A mixture of 6-benzyloxy-2-(4-hydroxyphenyl)-3-[4-[2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene (Part D) ,
4-bromobutyronitrile (1.2 mol/mol of phenol), and Cs2C03 (2
mol/mol of phenol) in DMF (about 10 mL/mmol of phenol) was
heated to 80 °C for 3 h, poured into 4 volumes of water and
extracted with EtOAc. After drying (K2C03) and evaporation,
the title compound was obtained as a foam in 98% yield
following MPLC (Si02; 0.5% in CHC13 sat'd with NH40H).
FDMS 603 (M+); Anal. calcd for C3gH38N203S: C, 75.72; H,
6.35; N, 4.65. Found: C, 75.66; H, 6.18; N, 4.72.
F. 6-Hydroxy-3- [4- [2- (1-pyrrolidinyl) ethoxy] benzyl] -2-
[4- (3-cyanopropyloxy)phenyl]benzo [b] thiophene.
O~N
\_/
HO
O~CN
By essentially following the debenzylation procedure
described in Example 10, the title compound was prepared as
an oil starting from 6-benzyloxy-3-[4-[2-(1-pyrrolidinyl)-
ethoxyJ benzyl ] -2 - [4 - ( 3 -cyanopropyloxy) phenyl J -
benzo[b]thiophene (Part E} in 71% yield following radial
chromatography (Si02; l.Oo in CHC13 sat'd with NH40H).
FDMS 513 (M+1); Anal. calcd for C31H32N2O3S: C, 72.63; H,
6.29; N, 5.46. Found: C, 72.87; H, 6.26; N, 5.52.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-67-
G. 6-Hydroxy-3- [4- [2- (1-pyrroiidinyl) ethoxy]benzyl] -2- [4-
(3-carboxypropyloxy)phenyl]benzo[b]thiophene Hydrochloride.
\ / O~N
w \
~ HCI
HO
O~C02H
A solution of 400 mg (0.83 mmol) of 6-hydroxy-3- [4- [2-
(1-pyrrolidinyl) ethoxy] benzyl] -2- [4- (3-cyanopropyloxy) -
phenyl] benzo [b] thiophene (Part F) in 5 mL of MeOH was
treated with 5 mL of 5 N aq HC1 and the mixture heated to
reflux for 24 h. The mixture was concentrated in vacuo.
The residue was reconstituted in 5 mL of dioxane and the
mixture treated with 5 mL of 5 N aq HC1. The solution was
heated to mild reflux for 6 h and was concentrated in vacuo.
The solid was dissolved in 5 mL of H20 and the solution
lyopholized to afford 300 mg (0.56 mmol; 68%) of the title
compound as a white solid.
FDMS 532 (M+1) .
Example 16
Preparation of 2-[4-[4-Methoxy-4-oxobutoxy]phenyl]-3-[3-
methoxy-4- [2- (1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene
Oxalate.
OMe N
C2H2O4
O
OMe
O
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-68-
A. 4-(2-Benzo[b]thiophenyl)phenyl Triisopropylsilyl Ether
i~
oY.~
A mixture of 2-(4-hydroxyphenyl)benzothiophene (2.84 g,
12.6 mmol), triethylamine (2.5 g, 25.2 mmol) and 30 mL dry
DMF was cooled in an ice bath and treated with triisopropyl-
silyl triflate (7.7 g, 25.2 mmol). The reaction was allowed
to warm to room temperature, quenched with 100 mL brine then
extracted twice with 50 mL EtOAc. The combined extract was
washed with brine, dried over MgS04 and concentrated to
dryness. The resulting solid was purified by
chromatrography (Si02, 5% EtOAc in Hexanes) to yield 4.7 g
(12.3 mmo1,98%) of a solid.
FDMS 382 (M+); 1H NMR (DMSO-d6) 8 7.95-7.9 (m, 1H). 7.82-
7.77 (m, 1H),7.72-7.70 (m, 2H), 7.65 (s, 1H), 7-4-7.27 (d,
2H), 7.0-6.92 (d, 2H), 1.35-1.18 (m, 3H), 1.15-1.05 (m, 18H)
B. 2-(4-Triisopropylsilyloxyphenyl)benzo[b]thiophen-3-yl
3-Methoxy-4-[2-(1-pyrrolidinyl)ethoxy]phenyl Ketone
O
N
. Si'
O
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-69-
A mixture of 3.5 g (11.6 mmol) of 4-[2-(1-pyrroli-
dinyl)ethoxy]-3-methoxybenzoic acid hydrochloride (see
below), 30 mL C1CH2CH2C1, 10 mL of oxalyl chloride and 1
drop of DMF was stirred at ambient temperature for 16 hours
then evaporated in vacuo, to dryness. The resulting solid
was disolved in 50 mL 1,2-dichloroethane and concentrated
under reduced pressure. It was redissolved in 100 mL 1,2-
dichloroethane and treated sequentially with a solution of
47 mL 1 M TiCl4 in CH2C12 and 4.4 g (11.6 mmol) of
4-(2-benzo[b]thiophenyl)phenyl triisopropylsilyl ether 0 °C.
The reaction was protected from light and stirred at 0 °C
for 4 h at which time it was quenched by carefully pouring
it into 400 mL of vigorously stirred saturated aqueous
NaHC03. Added 300 mL EtOAc and separated the layers. The
aqueous layer was treated with 200 mL saturated aqueous
sodium potassium tartrate and extracted twice with 100 mL
EtOAc. The combined organic layer was washed with brine,
dried over MgS04 and evaporated in vacuo to give an oil
which was purified by chromatography (Si02; Hex/THF/Et3N 85-
10-50) to afford 5.84 g (9.3 mmol; 80%) of the desired
compound as an oil.
FDMS 629 (M+); 1H NMR (CDC13) 8 7.82-7.85 (m, 1H), 7.7-7.5
(d, 1H), 7.5-7.45 (d, 1H}, 7.4-7.2 (d, 5H), 6.8-6.75 (d,
2H), 6.65-6.6 (m, 1H), 4.18 (t, 2H); 3.85 (s, 3H), 2.95 (t,
2H), 2.65-2.55 (m, 4H), 1.85-1.75 (m, 4H), 1.35-1.18 (m,
3H), 1.15-1 (m, 18H)
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-70-
C. 2-(4-Triisopropylsilyloxyphenyl)-3-[3-methoxy-4-[2-
(1-pyrrolidinyl)ethoxy)benzyl)benzo[b)thiophene.
N
O
.jl~
The above ketone (5.4 g , 8.6 mmol) was dissolved in
100 mL dry THF, cooled to 0 °C under nitrogen and treated
with 8.6 mL of 1 M lithum aluminum hydride in THF. The
reaction was stirred at 0 °C for 1 hour then quenched with a
saturated solution of Na2S04. Added 200 mL THF and filtered
through a pad of diatomaceous earth. Concentration yielded
5.17 g of a foam.
A mixture of the foam and triethylsilane (5 g, 43 mmol)
in 100 mL CH2C12,was cooled to 0 °C and treated with 9.8 g
(86 mmol) of trifluoroacetic acid. After stirring 45
minutes at 0 °C the solution was quenched with 100 mL
saturated aqueous NaHC03. The layers were separated and the
organic layer was dried over MgSO. Concentration to dryness
yielded an oil which was purified by chromatrography (Si02;
Hex/THF/Et3N 75-20-5%) to recover 4.9 g (7.96 mmol, 93%) of
the desired product as an oil.
FDMS 615 (M+); 1H NMR (CDC13) 8 7.85-7.8 (m, 1H). 7.6-7.5
(m, 1H),7.4-7.39 (m, 2H), 7-31-7.28 (d, 2H), 6.88 (d, 2H),
6.84 (d, 1H), 6.75 (d, 1H), 6.63-6.6 (m, 1H), 4.2 (s, 2H),
4.18 (t, 2H); 3.75 (s, 3H), 3.15-3.05 (m, 2H), 2.95-2.77 (m,
4H), 1.95-1.85 (m, 4H), 1.35-1.18 (m, 3H), 1.15-1.05 (m,
18H)
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-71-
D. 2-(4-Hydroxyphenyl)-3-[3-methoxy-4-[2-(1-pyrrolidinyl)-
ethoxy] benzyl] benzo [b] thiophene.
OMe
N
~ O
\ ~ _
S~
O-H
The above silyl ether (2 g, 3.25 mmol) was dissolved in
25 mL THF and treated with 2 g (34 mmol) of potassium
fluoride and 25 mL H20. The reaction was stirred for 16
hours at ambient temperature then refluxed for 1 hour. The
layers were separated and the aqueous layer was extracted
with 30 mL EtOAc. The combined organic layer was dried over
MgS04 and concentrated to an oily solid which was mixed with
5 mL hexanes and filtered to recover 1.04 g (2.3 mmol, 700)
of an off-white solid.
FDMS 460 (M+1); 1H NMR DMSO-d6) 8 (m, 1H). 7.58-7.55 (m,
1H}, 7.34-7.27 (m, 4H), 6.86-6.83 (m, 2H), 6.77-6.74 (m,
2H), 6.45 (d, 1H); 4.13 (s, 2H), 3.90 (t, 2H), 3.62 (s, 3H),
2.68 (t, 2H), 2.3-2.2 (m, 4H), 1.62-1.6 (m, 4H); Anal. Calcd
for C28H29N03S: C, 73.17; H, 6.36; N, 3.05; Found: C, 73.43;
H, 6.51; N, 3.12.
E. 2- [4- [4-Methoxy-4-oxobutoxy]phenyl] -3- [3-methoxy-4- (2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene Oxalate.
A mixture of the above benzothiophene (0.95 g,
2.1 mmol), cesium carbonate (2.7 g, 8.3 mmol) and 20 mL dry
DMF was treated with methyl-3-chlorobutyrate (315 ~,L,
2.6 mmol) and heated at 80 °C for 2 hours. The reaction
mixture was cooled to room temperature, poured into a
saturated aqueous solution of NaHC03 and extracted twice
CA 02287901 1999-10-29
WO 98/48798 PCT/L1S98/08700
-72-
with 30 mL EtOAc. The combined organic layer was washed
three times with 40 mL brine, dried over MgS04 and
concentrated to a solid. Purification by chromatrography
(Si02; Hex/THF/Et3N 65-30-5%) yielded 1.05 g of a white
solid which was converted to its oxalate salt.
FDMS 559 (M+); 1H NMR (CDC13) 8 7.85 (m, 1H), 7.5 (m, 1H),
7.43 (d, 2H). 7.35-7.23 (m, 2H), 6.93 (d, 2H), 6.72 (d, 1H),
6.7 (s, 1H), 6.61 (d, 1H), 4.21 (s, 2H), 4.17 (t, 2H), 4.09
(t, 2H), 3.70 (s, 3H); 3.75 (s, 3H), 2.94 (t, 2H), 2.6-2.64
(m, 4H), 2.55 (t, 2H), 2.2-2.1 (m, 2H), 1.83-1.78 (m, 4H)
Anal. Calcd for C33H37N05S~0.75 C2H204: C, 66.06; H, 6.19;
N, 2.23; Found: C, 66.12; H, 6.06; N, 2.17
The benzoic acid for Part B, above, may be obtained as
follows .
F. Methyl 3-Methoxy-4-(2-(1-pyrrolidinyl)ethoxy]-
benzoate.
OMe
N'
\O
The substituted pyrrolidine was prepared in 94%
yield by heating 4-hydroxy-3-methoxybenzoate with
excess 1-(2-chloroethyl)pyrrolidine hydrochloride and
K2C03 in DMF, followed by cooling, dilution into cold
water and extraction with EtOAc. The product was
obtained following drying (Na2S04) and evaporation.
1H NMR (CDC13) b 7.63 (d, 1H), 7.53 (s, 1H), 6.9 (d,
1H), 4.2 (t, 2H), 3.89 (s, 3H), 3.88 (s, 3H), 2.96 (t,
CA 02287901 1999-10-29
WO 98/48798 PCT/US98I08700
-73-
2H), 2.64-2.61 (m, 4H), 1.85-1.75 (m, 4H); FDMS 279
(M+) .
G. 3-Methoxy-4-[2-(1-pyrrolidinyl)ethoxy]benzoic Acid
Hydrochloride.
OH
N'
\O
The benzoic acid hydrochloride was prepared in 63%
yield from methyl 3-methoxy-4-[2-(1-pyrrolidinyl)-
ethoxy]benzoate by refluxing the above ester with
5N HCl, followed by mixing with toluene/EtOH before
evaporation to drynes. Trituration with hot EtOAc
afforded the benzoic acic hydrochloride.
1H NMR (DMSO-d6) 8 11.27 (bs, 2H), 7.57 (d, 1H), 7.55
(s, 1H), 7.12 (d, 1H), 4.44 (t, 2H), 3.82 (s, 3H), 3.5
(bs, 4H), 3.1 (bs, 2H); 1.98 (bs, 2H), 1.89 {bs, 2H);
Anal. Calcd for C14H1gN04~HC1: C, 55.72; H, 6.68; N,
4.64. Found: C, 56.01; H, 6.88; N, 4.70.
Example 17
Preparation of 2- (4- [4-Hydroxy-4-oxobutoxy]phenyl] -3- [3-
methoxy-4- [2- (1-pyrrolidinyl) ethoxy] benzyl] benzo (b] thiophene
Oxalate.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-74-
\O
O O
OH
O
S
O
HO
OH
O
The above ester (Example 16; 0.53 g, 0.95 mmol) was
added to a mixture of 50 mL THF, 20 mL EtOH and 4 mL 1 N
NaOH. The reaction was stirred 18 hours, neutralized with
4 mL 1 N HC1 and concentrated to dryness. The resulting
solid was mixed with 100 mL 50% MeOH in CHC13 and filtered.
The filtrate was concentrated to a solid then redissolved in
100 mL MeOH and converted to its oxalate salt by adding a
solution of 85 mg (0.95 mmol) of oxalic acid in 10 mL MeOH.
Concentration to dryness gave 586 mg (0.92 mmol, 97%) of a
solid.
FDMS 546 (M+1); 1H NMR (DMSO-d6) 8 10.6-10.8 (bs, 2H), 7.95-
7.91 (m, 1H), 7.6-7.58 (m, 1H), 7.43 (d, 2H). 7.32-7.29 (m,
2H), 7.03 (d, 2H), 6.81-6.85 (m, 2H), 6.5 (d, 2H), 4.21 (t,
2H), 4.19 (s, 2H), 4.0 (t, 2H), 3.65 (s, 3H); 3.5 (m, 2H),
3.2-3.0 (bs, 4H), 2.36 (t, 2H), 1.8-2.0 (m, 6H).
Example 18
Preparation of Methyl 4- [2- (Hydroxymethyl) -4- [3- [4- [2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophen-2-yl] -
phenoxy]butyrate Oxalate Salt.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98I08700
-75-
C2H204
O
O
HO
A. 2-[4-Trityloxy-3-(1,3-dioxolan-2-yl)phenyl]-
benzo Lb] thiophene .
/ \
\ ~ _~ ~ \ /
_ / \
0~
The title compound was prepared in 69o yield by
coupling benzo[bJthiophene-2-boronic acid and 2-(5-bromo-2-
trityloxyphenyl)-1,3-dioxolane using benzene, tetrakis-
(triphenylphosphine)palladium(0) and 2.0 N sodium carbonate
solution, vigorously stirred at 85 °C. Following cooling
and addition of brine, the layers were separated and the
aqueous layer extracted with EtOAc. After drying and
evaporation of the organic phase, the product was purified
by chromatography.
FDMS 540 (M+); base peak 243 (M-297); Anal. Calcd for
C36H2803S~ C, 79.97; H, 5.22. Found: C, 79.76; H, 5.44.
B. 3-Bromo-2-I4-trityloxy-3-(1,3-dioxolan-2-yl)phenyl]-
benzo [b1 thiophene .
Br
~~ OCPh3
S
-O
~J
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-76-
The title compound was prepared from the above
benzothiophene in quantitative yield by essentially
following the bromination procedure outlined above in
Example 3, Part A.
FDMS 620 (M+); Anal, calcd for C36H27Br03S~0.11CC14: C,
68.14; H, 4.28. Found: C, 68.14; H, 4.31.
C. 2-[4-Trityloxy-3-(1,3-dioxolan-2-yl)phenyl]-
benzo[b]thiophene-3-carboxaldehyde.
O
;Ph3
3-Bromo-2-[4-trityloxy-3-(1,3-dioxolan-2-yl)phenyl]-
benzo[b]thiophene (Part B; 28.7 g, 46.2 mmol) was dissolved
in 300 mL of freshly distilled THF and cooled to -78 °C. To
the solution was added 1.6 M n-BuLi in hexanes (34.7 mL,
55.5 mmol) dropwise over a period of 1 h. The dark brown
solution was stirred at -78 °C for 1.5 h. Dry DMF (14.3 mL,
185 mmol) was then added dropwise over 20 min and the
reaction mixture was slowly warmed to room temperature and
stirred for 19 h. The reaction was quenched with 300 mL of
satd NH4C1 solution. The mixture was extracted (3 x 1 L)
with EtOAc. The combined organic layers were dried over
Na2S04 and concentrated under reduced pressure.
Purification by column chromatography on the PrepLC (silica
gel, 0% to 6% to 10% EtOAc-Hexanes) afforded 6.70 g (11.8
mmol, 25%) of a white foam.
FDMS 243 (M-325); 325 (M-243); Anal. Calcd for
C37H2804S~0.15CH2C12: C, 76.74; H, 4.91. Found: C, 76.69;
H, 5.15.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_77-
D. 2- [4-Trityloxy-3- (1, 3-dioxolan-2-yl)phenyl] -a- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene-3-methanol.
,Ph3
The title compound was prepared in 77% yield by
treating 2-[4-trityloxy-3-(1,3-dioxolan-2-yl)phenyl]-
benzo[b]thiophene-3-carboxaldehyde (Part C) with 4-[2-
(1-pyrrolidinyl)ethoxy]phenyl magnesium bromide in THF at 0
°C. The reaction was quenched at 0 °C with saturated
aqueous NH4C1 solution and extracted with EtOAc. The
combined organic layers were dried (MgS04), evaporated and
purified by flash chromatography.
1HNMR (CDC13) b 7.75 (d, J = 7.8 Hz, 1H), 7.66 (d, J = 7.7
Hz, 1H), 7.58 (d, J = 2.3 Hz, 1H), 7.49 (d, J = 7.1 Hz, 6H),
7.14-7.31 (m, 12H), 6.89-6.99 (m, 2H), 6.81 (d, J = 8.7 Hz,
2H), 6.45 (d, J = 8.6 Hz, 1H), 6.27 (s, 1H), 6.05 (s, 1H),
4.24 (t, J = 5.3 Hz, 2H), 3.99 (m, 4H), 3.12 (dist t, 2H),
2.96 (m, 4H), 1.94 (m, 4H); FDMS 760 (M+) base peak 243
(M-517).
E. 2- [4-Hydroxy-3- (1, 3-dioxolan-2-yl)phenyl] -a- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene-3-methanol.
OH
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-78-
To a solution of (1.74 g, 2.29 mmol) of 2-[4-trityloxy-
3- (1, 3-dioxolan-2-yl) phenyl] -a- [4- [2- (1-pyrrolidinyl) -
ethoxy] phenyl] benzo [b] thiophene-3-methanol (Part D) in 23 mL
of a THF-EtOH mixture (1:1 ratio) was added (0.50 mL, 4.57
mmol) of anisole followed by addition of 1.75 g of 10% Pd on
carbon. The black slurry was stirred at room temperature.
under hydrogen (balloon pressure) for 24 h. The slurry was
filtered through a pad of diatomaceous earth and rinsed with
warm EtOH. The filtrate was concentrated. Purification by
flash chromatography (silica gel, 7% to 9%[loo conc NH40H in
MeOH]/CH2C12) afforded 954 mg (1.84 mmol, 81%) of a yellow
foam.
1
HNMR (CDC13) 8 7.79 (d, J = 8.0 Hz, 1H), 7.71 (d, J = 7.9
Hz, 1H}, 7.40 (d, J = 2.2 Hz, 1H), 7.17-7.36 (m, 5H), 6.91
(d, J = 8.4 Hz, 1H), 6.82 (d, J = 8.6 Hz, 2H), 6.16 (s, 1H),
5.93 (s, 1H), 5.29 (s, 1H), 4.03-4.16 (m, 6H), 2.96 (dist t,
2H), 2.74 (m, 4H), 1.83 (m, 4H); FDMS 517 (M+).
F. Methyl 4-[2-(1,3-Dioxolan-2-~l)-4-[3-[a-hydroxy-4-
[2- (1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophen-2-yl] -
phenoxy]butyrate.
0
~o
~-.~o-
The title compound was prepared in 54% yield by
essentially following the procedures outlined in above in
Example 1, Part E from the above phenol (Part E) and methyl
4-chlorobutyrate.
FDMS 618 (M+); Anal. calcd for C35H39N07S: C, 68.05; H,
6.36; N, 2.27. Found: C, 68.28; H, 6.58; N, 2.43.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-79-
G. Methyl 4- [2- (Hydroxymethyl) -4- [3- [4- [2- (1-pyrro-
lidinyl) ethoxy] benzyl] benzo [b] thiophen-2 -yl] phenoxy] -
butyrate.
f N
O
~O
~~(/O-
The title compound was prepared in 25% yield from
methyl 4- [2- (1, 3-dioxolan-2-yl) -4- [3- [a-hydroxy-4- [2-
(1-pyrrolidinyl ) ethoxy] benzyl] benzo [b] thiophen-2-yl] -
phenoxy]butyrate (Part F) by essentially following the
procedures outlined above in the second part of Example 8,
Part B.
FDMS 560 (M+); Anal. Calcd for C33H37N05S~0.75CH2C12: C,
65.02; H, 6.22; N, 2.25. Found: C, 65.03; H, 6.40; N, 2.39
H. Methyl 4- [2- (Hydroxymethyl) -4- [3- [4- [2- (1-pyrroli-
dinyl) ethoxy] benzyl] benzo [b] thiophen-2-yl] phenoxy] butyrate
Oxalate Salt.
czx2o4
0
~o
xo ~.1~~
The salt was prepared from the above ester (Part G) in
91% yield by treatment of a solution the ester in EtOAc with
a solution of oxalic acid (2+ molar equivalents) in EtOAc,
and filtration and drying of the resulting precipitate.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-80-
FDMS 559 (M+); Anal. calcd for C33H37N05S~1.OC2H204: C,
64.70; H, 6.05; N, 2.16. Found: C, 64.56; H, 6.28; N,
2.07.
Example 19
Preparation of Methyl 4- [2-Formyl-4- [3- (4- [2- (1-pyrroli-
dinyl) ethoxy] benzyl] benzo [b] thiophen-2-yl] phenoxy] butyrate
Oxalate Salt.
C2H204
O
O
H
A. Methyl 4- [2-Formyl-4- [3- [a-hydroxy-4- [2- (1-pyrroli-
dinyl) ethoxy] benzyl] benzo [b] thiophen-2-yl] phenoxy] butyrate.
~ N
O
~O
~~(/H
0-
A solution of methyl 4-[2-(1,3-dioxolan-2-yl)-4-[3-
[a-hydroxy-4- [2- (1-pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenoxy]butyrate (Example 18, Part F; 160 mg,
0.259 mmol) in 2.6 mL of AcOH/H20 mixture {4:1 ratio) was
stirred at room temperature for 1 h 40 min. The reaction
mixture was then concentrated under reduced pressure and
azeotroped with benzene to afford 149 mg (0.259 mmol,
quantitative yield) of an off-white foam.
FDMS 573 (M+); Anal. calcd for C33H35N06S: C, 69.09; H,
6.15; N, 2.44. Found: C, 68.84; H, 5.91; N, 2.57.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-81-
B. Methyl 4- [2-Formyl-4- [3- [4- [2- (1-pyrrolidinyl) -
ethoxy] benzyl] benzo [b] thiophen-2-yl] phenoxy] butyrate .
~ N
O
~O
H
O-
The title compound was prepared in 79% yield by
essentially following the procedures outlined above in the
second part of Example 8, Part B (except the reaction was
quenched after 1 min.) from the above carbinol (Part A).
FDMS 558 (M+); Anal. calcd for C33H35N~5S: C, 71.07; H,
6.33; N, 2.51. Found: C, 70.79; H, 6.32; N, 2.22.
C. Methyl 4- [2-Formyl-4- [3- [4- [2- (1-pyrrolidinyl) ethoxy] -
benzyl]benzo[b]thiophen-2-yl]phenoxy]butyrate Oxalate Salt.
CzHzOa
O
~O
~~J/H
The title compound was prepared in 87o yield by
essentially following the procedures outlined above in
Example 18, Part H from the above ester (Part B).
FDMS 557 (M+); Anal. Calcd for C33H35N~5S'0.78C2H204: C,
66.11; H, 5.87; N, 2.23. Found: C, 66.09; H, 5.95; N,
2.19.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-82-
Example 20
Preparation of (S)-6-Hydroxy-3-[3-methoxy-4-[(2-ethoxy-
carbonyl-5-oxopyrrolidin-1-yl)methyl]benzyl]-2-[4-
[2- (1-pyrrolidinyl) ethoxy]phenyl]benzo [b] thiophene.
\ COZEt
O
O
N
~ /~ o
-_
W~ \
H. i o
N
A. 1-Bromo-4-[2-(t-butyldimethylsilyloxy)ethoxy]benzene.
Bra
~ O, /
O S I~~
To a solution of 2-(4-bromophenoxy)ethanol (10.94 g,
50.4 mmol), in dry DMF (50 mL), was added t-butyldimethyl-
silyl chloride (7.6 g , 50.4 mmol) and imidazole (3.77g ,
55.5 mmol). The reaction was stirred at ambient temperature
for 18 h, then partitioned with hexane (300 mL) and water
(300 mL). The aqueous layer was extracted with hexane
(3x100 mL). The combined organic extracts were dried
(MgS04) and the solvent removed under reduced pressure to
give the desired product as an oil (16.6 g, 99%).
1H NMR (CDC13) 8 7.37 (d, J= 8.6 Hz, 2H), 6.80 (d, J= 8.6
Hz, 2H) , 4.00 (t, J= 6. 0 Hz, 2H) , 3 .98 (t, J= 6.0 Hz, 2H) ,
0.91 (s, 6H), 0.10 (s, 9H).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-83-
B. 6-Benzyloxy-2-[4-[2-(t-butyldimethylsilyloxy)ethoxy]-
phenyl]benzo[b]thiophen-3-yl 3-Methoxy-4-[(1-pyrrolidinyl)-
methyl]phenyl Ketone.
o
OTBS
The above bromide (1.25 g, 3.39 mmol), in THF (1.5 mL),
was added to a mixture of THF (1.5 mL) and Mg°. The
material was stirred at 60 °C for 1 h, during which time the
Mg° dissolved. This solution was then added, via syringe,
to a THF (5 mL) solution of 6-benzyloxy-2-(dimethylamino)-
benzo[b]thiophen-3-yl 3-methoxy-4-(1-pyrrolidinylmethyl)-
phenyl ketone (1.1 g, 2.26 mmol). After 1 h, the solution
was diluted 25 fold with EtOAc, the organics washed with
saturated NH4C1 solution and concentrated under reduced
pressure. Material was purified by flash chromatography
(Si02, 10% MeOH in CHC13); yielding 827 mg (50%).
1H NMR (CDC13) b 7.63 (d, J=8.7 Hz, 1H), 7.49 (d, J=4.3 Hz,
2H), 7.21-7.43 (m, 8H), 7.15 (dd, J=2.1, 8.7 Hz, 1H), 6.95
(d, J=6.4 Hz, 1H), 6.75 (d, J=8.7 Hz, 2H), 5.17 (s, 2H),
3.90-4.0 (m, 4H), 3.80 (s, 3H), 3.65 (s, 2H), 2.55 (s, 4H),
1.90 (s, 4H), 0.95 (s, 9H), 0.15 (s, 6H).
C. 6-Henzyloxy-2-[4-[2-(t-butyldimethylsilyloxy)ethoxy]-
phenyl]benzo[b]thiophen-3-yl (S)-3-Methoxy-4-[(2-ethoxy-
carbonyl-5-oxopyrrolidin-1-yl)methyl]phenyl Retone.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-84-
\Et02 \
N
O
OTBS
A solution of the above amine (254 mg, 0.359 mmol) in
CHC13 (1 mL) was added to a solution of cyanogen bromide (42
mg, 0.395 mmol) in CHC13 (1 mL). After completion of the
reaction, as indicated by TLC, the mixture was diluted 25
fold with EtOAc, the organics washed with saturated NaHC03
solution and H20, and concentrated under reduced pressure.
To this crude residue was added the sodium salt of
L-pyroglutamic acid ethyl ester (281 mg, 1.79 mmol,
preformed from an equimolar amount of NaH in 1 mL of THF)
and the mixture stirred at 60 °C for 35 min. After diluting
25 fold with EtOAc, the organics were washed with saturated
NaHC03 solution, H20, and concentrated under reduced
pressure. Material was purified by flash chromatography
(Si02, 20% Hexane in EtOAc); yielding the title compound in
81o yield from the amine.
1H NMR (CDC13) 8 7.58 (d, J=8.9 Hz, 1H), 7.21-7.46 (m, lOH),
7.05 (dd, J=1.7, 6.5 Hz, 2H), 6.74 (d, J=8.8 Hz, 2H), 5.13
(s, 2H), 4.45 (q, J=15.0, 20.5 Hz, 2H), 4.15 (m, 2H), 3.89-
3.98 (m, 4H), 3.82 (dd, J=3.5, 9.1 Hz, 1H), 3.74 (s, 3H),
1.98-2.51 (m, 4H), 1.22 (t, J=7.0 Hz, 3H), 0.88 (s, 9H),
0.06 (s, 6H); FDMS 793.7.
D. 6-Benzyloxy-2- [4- [2- (1-imidazolyl) ethoxy] phenyl] -
benzo[b]thiophen-3-yl (S)-3-Methoxy-4-[(2-ethoxycarbonyl-
5-oxopyrrolidin-1-yl)methyl]phenyl Ketone.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_85_
Et02C
O
N
O
w
N
To the above silyl ether (218 mg, 279 mmol) in THF
(1 mL) was added 1.0 M TBAF (0.28 mL, 0.28 mmol) and the
mixture stirred at room temperature for 45 min. After
diluting 50 fold with EtOAc, the organics were washed with
H20 and concentrated under reduced pressure. The resulting
residue was purified by flash chromatography (Si02, 5% MeOH
in EtOAc). This compound was then taken up in pyridine
(0.5 mL) and methanesulfonyl chloride (47 mg, 0.418 mmol)
added. The mixture was stirred, under N2, for 35 min and
then pyrrolidine (388 mg, 5.58 mmol) added and the solution
heated at 60 °C for 45 min. After cooling, the mixture was
diluted 50 fold with EtOAc and the organics washed with
saturated NaHC03 and H20 and concentrated under reduced
pressure. Material was purified by flash chromatography
(Si02, 15% MeOH in EtOAc, 1% Et3N v/v added); yielding the
title compound in 83% yield from the silyl ether.
1H NMR (CDC13) 8 7.58 (d, J=8.9 Hz, 1H), 7.21-7.46 (m, lOH),
7.05 (dd, J=1.8, 9.0 Hz, 2H), 6.75 (d, J=8.7 Hz, 2H), 5.13
(s, 2H), 4.43 (q, J=15.1, 19.1 Hz, 2H), 4.01 4.16 (m, 4H),
3.85 (dd, J=3.4, 9.0 Hz, 1H), 3.74 (s, 3H), 2.84 (t, J=5.9
Hz, 2H), 2.58 (s, 4H), 1.81-2.57 (m, 4H), 1.78 (s, 4H), 1.22
(t, J=7.3 Hz, 3H); FDMS 733 (M+).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-86-
E. (S)-6-Hydroxy-3-[3-methoxy-4-[(2-ethoxycarbonyl-5-oxo-
pyrrolidin-1-yl)methyl]benzyl] -2- [4- [2- (1-pyrrolidinyl) -
ethoxy] phenyl] benzo [b] thiophene.
To the above benzyl ether (74 mg, 0.101 mmol) was added
aqueous ammonium formate (1 mL of 25o w/v), THF (1 mL), and
Pd/C (10%, 74 mg). The mixture was rapidly stirred at room
temperature for 2 h and then diluted 25 fold with THF and
passed through a pad of diatomaceous earth. The filtrate
was concentrated under reduced pressure and the resulting
residue purified by flash chromatography (Si02, loo MeOH in
CHC13).
1H NMR (CDC13) b 7.54 (d, J=9.4 Hz, 1H), 7.01-7.31 (m, 4H0,
7.00 (d, J=7.8 Hz, 1H), 6.88 (d, J=2.3 Hz, 1H), 6.85 (s,
1H), 6.57 (d, J=8.7 Hz, 2H), 4.40 (q, J=15.1, 21.3 Hz, 2H),
4.05-4.16 (m, 4H), 3.81 (dd, J=3.2, 8.8 Hz, 1H), 3.71 (s,
3H), 2.96 (s, 2H), 2.82 (s, 4H), 1.98-2.51 (m, 4H), 1.87 {s,
4H) , 1.22 (t, J=4.2 Hz, 3H) ; FAB MS 643.2 (M+ 1) .
Example 21
Preparation of (S)-6-Hydroxy-3-[3-methoxy-4-[(2-carboxy-
5-oxopyrrolidin-1-yl)methyl]benzyl]-2-[4-[2-(1-pyrroli-
dinyl) ethoxy] phenyl] benzo [b] thiophene Hydrochloride.
COZ H
O
N
O
HO
HCI
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_87_
To the above ester (Example 20, Part E; 42 mg,
0.065 mmol) was added NaOH (5 mg, 0.130 mmol) and EtOH (95%,
0.5 mL) and the mixture stirred at room temperature for 2 h.
After concentrating under reduced pressure, the salt was
taken up in H20 (5 mL) and the pH lowered to 3 by addition
of 6 N HC1 and reconcentrated. The material was then
purified by semi-preparative HPLC, using a (VYDAC) C18
column (25 x 250 mm), and following a gradient elution 98:2
(H20 with 0.1% HCl added/CH3CN) to 50:50. This yielded 40
mg (94%) of the title compound.
1H NMR (CD30D) 8 7.52 (d, J=7.8 Hz, 1H), 7.25-7.30 (m, 4H),
7.18 (d, J=6.7 Hz, 1H), 7.02 (d, J=7.8 Hz, 1H), 6.84-6.91
(m, 3H), 4.38 (q, J=15.1, 197 Hz, 2H), 4.27 (s, 2H), 3.84
(dd, J=2.8, 8.6 Hz, 1H), 3.72 (s, 3H), 3.68 (s, 2H), 3.61
(s, 2H), 3.18-3.20 (m, 2H), 2.03-2.43 (m, 8H); FAB MS 615
(M + 1) .
Example 22
Preparation of 2- [4- [2- (Hydroxy) ethoxy] phenyl] -3- [4- [2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene Oxalate .
O~NV
s'
'~O ~Ohi C 2H 20 a
A. 2- [4- [2- (tert-Butyldiphenylsilyloxy) ethoxy] phenyl] -
3- [4- [2- (1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
O~NV
S
I / O ~OTBDPS
A mixture of 2.00 g (4.66 mmol) of 2-(4-hydroxyphenyl)-
3- [4- [2- (1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-88-
(Example 8, Part C), 1.86 g (5.12 mmol) of 1-bromo-2-(tert-
butyldiphenylsilyloxy)ethane, and 1.93 g (14.0 mmol) of
K2C03 in 50 mL DMF was heated to 50 °C for 22 h. The
reaction was poured into 250 mL of H20 and the mixture
extracted with EtOAc (3 x 100 mL). The combined organic
extracts were washed with H20 (2 x 100 mL), dried over
K2C03, filtered and concentrated in vacuo to give 4.21 g of
an oily solid. Purification by flash chromatography (Si02;
O.lo then 0.2o then 0.5o MeOH in CHC13 sat'd with NH40H)
afforded 2.76 g (3.88 mmol; 83%) of the title compound as an
oil.
FDMS 711 (M+}; Anal. calcd for C45H49N03S: C, 75.91; H,
6.94; N, 1.97. Found: C, 76.05; H, 6.98; N, 2.12.
B. 2- [4- [2- (Hydroxy) ethoxy]phenyl] -3- [4- [2- (1-
pyrrolidinyl)ethoxy]benzyl]benzo[b]thiophene Oxalate.
By essentially following the conditions described in
Example 20, Part A, for the removal of the protecting group,
the title compound was prepared as a solid from the above
silyl ether in 93% yield following flash chromatography
(Si02; 2% then 4% MeOH in CHC13 sat'd with NH40H).
FDMS 473 (M+); Anal. calcd for C29H31NO3S.C2H2O4: C, 66.06;
H, 5.91; N, 2.49. Found: C, 65.88; H, 5.68; N, 2.58.
Example 23
Preparation of 6-Hydroxy-2-[4-(2-hydroxyethoxy)phenyl]-
benzo[b]thiophen-3-yl 3-Methoxy-4-[(4-morpholinyl)methyl]-
phenyl Ketone Oxalate.
OMe
O ~ N~1
~O
HO S ~ ~OH
~O
C 2H2~4
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_89_
A. 2-(4-Bromophenoxy)ethyl Triisopropylsilyl Ether.
Br-~-O
OTIPS
Triisopropylsilyl trifluoromethanesulfonate (24.4 mL,
90.7 mmol) was added to a stirred solution of 2-(4-bromo-
phenoxy)ethanol (15.1 g, 69.8 mmol) and anhydrous
triethylamine (19.4 mL, 140 mmol) in anhydrous CH2C12 (30
mL) at 0 °C under nitrogen atmosphere. The resultant
mixture was stirred for 1 h. The mixture was washed with
saturated NaHC03 (25 mL), extracted with EtOAc (3 x 75 mL),
dried over MgS04, filtered, concentrated, and
chromatographed on silica (10% CH2C12 in hexanes) to give
23.4 g (900) of the silyl ether as a colorless liquid.
IR (thin film) 2944, 1489 cm'1; FDMS m/e 372 (M+, 79Br) and
374 (M+, 8lBr). Anal. Calcd. for C17H29Br02Si: C, 54.68; H,
7.83. Found: C, 54.97; H, 7.55.
B. 6-Benzyloxy-2- [4- [2- (hydroxy) ethoxy] phenyl] -
benzo[b]thiophen-3-yl 3-Methoxy-4-[(4-morpholinyl)-
methyl]phenyl Ketone.
OMe
_/
O
I ~~
Bn0 S ~~ OOH
O
The above silyl ether (2.71 g, 7.26 mmol) was added to
a stirred suspension of magnesium ribbons (164 mg, 6.77
mmol) in anhydrous THF (4 mL) under argon atmosphere,
followed by the addition of a small iodine chip. The
resultant mixture was heated in an oil bath at 60-65 °C for
1.5 h to form a homogeneous Grignard solution. The Grignard
solution was cooled to room temperature and diluted with
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-90-
anhydrous THF (10 mL) before it was added to a stirred
solution of 6-benzyloxy-2-(dimethylamino)benzo[b]thiophen-3-
yl 3-methoxy-4-[(4-morpholinyl)methyl]phenyl ketone (2.50 g,
4.84 mmol) in anhydrous THF (10 mL) at 0 oC under argon
atmosphere. The resultant mixture was stirred at 0 oC for
1.5 h, then quenched with saturated aqueous NH4C1 (15 mL).
After extraction with EtOAc (70 mL x 2), the combined
organic layers were dried over MgS04, filtered, and
concentrated to give a gummy residue which was dissolved in
anhydrous THF (25 mL) and treated with tetrabutylammonium
fluoride (5.80 mL, 1 M in THF) at room temperature under
nitrogen atmosphere. After stirring for 1 h, the mixture
was concentrated under vacuum; the residue was
chromatographed on silica [gradient 0-30o MeOH/Et3N (2/1) in
EtOAc] to give 2.61 g (88%) of the keto alcohol as a foam.
IR (neat) 3426 (br), 1646, 1605 cm-1; FDMS m/e 609 (M+);
Anal. Calcd. for C36H35NOsS: C, 70.91; H, 5.79; N, 2.30.
Found: C, 70.63; H, 5.65; N, 2.04.
C. 6-Hydroxy-2- (4- (2-hydroxyethoxy)phenyl]benzo[b] thio-
phen-3-yl 3-Methoxy-4-[(4-morpholinyl)methyl]phenyl Ketone
Oxalate.
Using a debenzylation procedure similar to that
described above in Example 20, Part E, followed by formation
of the oxalate using a procedure similar to that described
above in Example 18, part H, the title diol was obtained
from the above benzyloxy alcohol as a yellow solid in an
overall 50% yield.
IR (KBr) 3420 (br), 3350-2250 (br), 1640, 1607 cm-1;
FABMS m/e 520 (M++1-1[C2H204]); Anal. Calcd. for
C29H2gN06S~C2H204: C, 61.07; H, 5.13; N, 2.30. Found: C,
61.12; H, 5.21; N, 2.16.
Example 24
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-91-
Preparation of 3-Methoxy-4-[(5-tetrazolyl)methyl]phenyl
2- [4- [2- (1-Pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophen-3-yl
Ketone Oxalate.
OMe H
I
O N~N
v //~~ _N
N
_ . N
O
C2H204
A. Methyl 4-Cyanomethyl-3-methoxybenzoate.
OMe
Me0 2C
CN
AIBN (274 mg) was added to a stirred suspension of
methyl 3-methoxy-4-methylbenzoate (20.10 g, 112.0 mmol) and
NBS (23.84 g, 134 mmol) in CC14 (730 mL), and the resultant
mixture was heated to reflux for 3 h. At room temperature,
the mixture was diluted with hexanes (350 mL) before it was
filtered and concentrated to give 28.59 g (crude yield 99%)
of the brominated product.
Part of the crude brominated product (8.10 g) was
dissolved in anhydrous THF (70 mL). 18-Crown-6 (413 mg,
1.56 mmol) was added followed by KCN (3.05 g, 46.9 mmol);
then the resulting mixture was heated at 65 °C for 20 h.
The reaction mixture was diluted with H20 (50 mL) and EtOAc
(250 mL), then the aqueous layer was extracted with EtOAc (2
x 100 mL). The combined organic layers were dried over
MgS04, filtered, and concentrated to give an oily residue,
which was chromatographed on silica [gradient 5-200 EtOAc in
hexanes] to provide 2.50 g of the cyanomethyl compound (390)
as a white solid.
IR (KBr) 2260, 1714, cm-1; FDMS m/e 205 (M+).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-92-
B. 4-Cyanomethyl-3-methoxybenzoyl Chloride.
Using procedures similar to those described above in
Example 1, Part C, the above benzoate was hydrolyzed and
converted into the corresponding benzoyl chloride.
C. 4-Cyanomethyl-3-methoxyphenyl 2-[4-[2-(1-Pyrrolidinyl)-
ethoxy]phenyl]benzo[b]thiophen-3-yl Ketone.
OMe
O ~--\
CN
~I_S I
~~O~-N
Following a procedure similar to that described in
Example 1, Part C, the ketone was obtained from the above
benzoyl chloride and 2 - [4 - [ 2 - ( 1-pyrrol idinyl ) ethoxy] phenyl ] -
benzo[b]thiophene (obtained by coupling benzo[b]thiophene-
2-boric acid and 4-[2-(1-pyrrolidinyl)ethoxy]-1-bromobenzene
using a procedure similar to that of Example 18, Part A).
Column chromatography on silica [gradient 60-90o THF in
hexanes] gave 190 mg (41a) of the ketone as a yellow oil.
IR (thin film) 2965, 2256, 1651, 1606 cm-1; FDMS m/e 497
(M++1); Anal. Calcd. for C3pH2gN203S: C, 72.56; H, 5.68; N,
5.64. Found: C, 72.72; H, 5.93; N, 5.60.
D. 3-Methoxy-4-[(5-tetrazolyl)methyl]phenyl 2-[4-[2-
(1-Pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophen-3-yl Ketone
Oxalate.
Acetic acid (0.055 mL, 0.957 mmol) and sodium azide
(62.2 mg, 0.957 mmol) were sequentially added to a stirred
solution of the above nitrile (190 mg, 0.383 mmol) in n-BuOH
(0.4 mL) at room temperature under nitrogen atmosphere. The
mixture was heated to 90 °C and stirred for 16 h. The
reaction mixture was allowed to cool to room temperature and
without workup the reaction mixture was chromatographed on
silica [gradient 0-10% MeOH in CH2C12] to give 30.1 mg (15a)
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-93-
of a gum. Following a procedure similar to that described
in Example 18, Part H, the title compound was obtained from
the gum as a beige solid in 86% yield.
IR (KBr) 3450 (br), 2800-2200 (br), 1731, 1646, 1605 cm-1;
FABMS m/e 540 (M++1-1[C2H204]).
Example 25
Preparation of 3-[3-Methoxy-4-[(5-tetrazolyl)methyl]benzyl]-
2- [4- [2- (1-pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophene
Oxalate.
OMe
N-
~N
~I ~ N
S I ~ N
w
O
C2H202
A. 3-Methoxy-4-[[1-(triphenylmethyl)tetrazol-5-yl]-
methyl] phenyl 2- [4- [2- (1-Pyrrolidinyl) ethoxy] phenyl] -
benzo[b]thiophen-3-yl Retone.
OMe trityl
O ~-~~N _ N
N,N
S '~ O~. N
Trimethyltin azide (288 mg, 1.39 mmol) was added to a
stirred solution of the nitrile of Example 24, Part C, (434
mg, 0.874 mmol) in 1 mL anhydrous toluene, at room
temperature, under a nitrogen atmosphere. The resulting
mixture was refluxed for 17 h, then cooled to room
temperature and 5N NaOH (0.29 mL, 1.39 mmol) was added
causing the mixture to solidify. THF (3 mL) was added and
the mixture was manually stirred for about 20 min, then
tritylbromide (480 mg, 1.49 mmol) was added at room
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-94-
temperature and stirred for 2.5 h. The resulting mixture
was diluted with 5 mL H20 and 25 mL EtOAc. The mixture was
then washed with a saturated solution of NaHC03 and the
aqueous layer was extracted with EtOAc (2 x 15 mL). The
organics were dried over MgS04, filtered, concentrated, and
chromatographed on silica [gradient 0-loo EtOH/Et3N (2/1)
10-30% THF in hexanes] to give 400 mg (590) of the protected
keto tetrazole as a yellow oil.
IR (Thin film) 2927 (br), 1654, 1506 cm-1; FDMS m/e 782
{M++1).
B. 3- [3-Methoxy-4- [ (5-tetrazolyl)methyl] benzyl] -2- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene.
H
OMe t
N.N
W n
N
0~~. N
DIBAL-H (0.48 mL, 1 M in toluene) was added to a
stirred solution of the above ketone (151 mg, 0.192 mmol) in
anhydrous CH2C12 (2 mL) at -15 oC under a nitrogen
atmosphere. The resultant solution was stirred at -15 °C
for 1.5 h. The reaction mixture was treated sequentially
with MeOH (1.0 mL), diluted with EtOAc (10 mL), and
saturated aqueous Rochelle's salt solution (10 mL). The
two-layered solution was stirred vigorously at room
temperature for 1 h. After extraction with EtOAc (2 x 10
mL), the organic layer was dried over MgS04, filtered,
concentrated, and chromatographed on silica to give 47 mg
(310? of the desired alcohol.
The above alcohol was dissolved in anhydrous CH2C12 (1
mL) and cooled to 0 oC before it was sequentially treated
with TFA (0.056 mL, 0.721 mmol) and Et3SiH (0.067 mL, 0.421
mmol). The resultant mixture was stirred at 0 oC for 1 h.
After cautious treatment with saturated aqueous NaHC03 to
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-95-
neutralize TFA, the mixture was allowed to warm to room
temperature where it was extracted with EtOAc (3 x 5 mL).
The combined organic layers were dried over MgS04, filtered,
concentrated to give the methylene compound as a crude gummy
residue.
C. 3- [3-Methoxy-4- [ (5-tetrazolyl)methyl]benzyl] -2- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzolb]thiophene Oxalate.
The crude product from Part B, above, was dissolved in
THF (1 mL), and the solution was stirred and treated with a
solution of oxalic acid (8.1 mg) in THF/EtOAc (1 mL/1 mL) to
form a suspension. An additional 2 mL of EtOAc was added to
the suspension. After filtration and subsequent drying
under vacuum at 50 °C, 20.1 mg (53%) of the title compound
was obtained as a white solid.
1H NMR 8 1.90 (br 4H), 3.29 (br s, 4H}, 3.52
(DMSO-d6) s,
(br s, 2H),3.61 (s, 3H), 4.06 (s, 2H), 4.20 (s, 2H), 4.30
(br s, 2H) 6.51 (d, J = 7.3 1H), 6.80 (s, 1H), 6.97 (d,
Hz,
J 7.3 1H), 7.10 (d, J 31 (m, 2H),
= Hz, = 8.3 Hz,
2H), 7.
7.47 (d, = 8.3 Hz, 2H) , 7.58(m, 1H) , 7. (m, 1H) .
J 93
Example 26
Preparation of 4-[2-Formyl-4-[3-[4-[2-(1-pyrrolidinyl)-
ethoxy] benzyl] benzo [b] thiophen-2-yl] phenoxy] butyric Acid
Sodium Salt.
O
Na+
The title compound was prepared by adding 179 ~tL (0.179
mmol) of 1 N NaOH to a solution of 100 mg (0.179 mmol)
methyl 4- [2-formyl- [3- [4- [2- (1-pyrrolidinyl) ethoxy] -
CA 02287901 1999-10-29
WO 98/48798 PCTlUS98/08700
-96-
benzyl]benzo[b]thiophen-2-yl]phenoxy]]butyrate (Example 19,
Part B) dissolved in 1.0 mL of l:l THF:MeOH mixture. The
solution was stirred at room temperature for 22 h. The
reaction mixture was then evaporated in vacuo and dried in a
vacuum oven at 55 °C over P205 to yield the title compound
(101.4 mg, 0.179 mmol, quantitative yield) as a light yellow
solid.
mp 214-217 °C (dec); IR (RBr) 3400 (br), 1685, 1607, 1571
cm-1; Ion Spray MS 544 (M+1)+; 456 (M-87)-; Anal. Calcd
for C32H32N05S~Na: C, 67.95; H, 5.70; N, 2.48. Found: C,
68.13; H, 5.94; N, 2.73.
Example 27
Preparation of 3- [4- (2-Ethoxy-2-oxoethoxy)benzyl] -2- [4- [2-
(1-pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophene
Hydrochloride.
'O
HCI
N
A solution of 3-(4-hydroxybenzyl)-2-[4-[2-(1-pyrroli-
dinyl ) ethoxy] phenyl] benzo [b] thiophene in DMF ( 70 mL) was
treated with sodium hydride (100 mg, 60% in mineral oil, 2.5
mmol) for 10 minutes and then with ethyl bromoacetate (0.3
mL, 2.7 mmol) for 20 minutes. The mixture was diluted with
EtOAc and water. The organic phase was washed with water,
washed with brine, dried over sodium sulfate, and evaporated
in vacuo. The residue was chromatographed on silica gel,
eluting with a gradient (0-4% MeOH/CH2C12), to give the
product free base as an oil (860 mg, 82%). The
hydrochloride salt was precipitated from a CH2C12-Et20
solution as an amorphous solid.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_97_
FDMS m/e 516.1 (M+)
Analysis for C31H33N04S~HC1:
Calcd: C, 67.44; H, 6.21; N, 2.54;
Found: C, 67.70; H, 6.23; N, 2.57.
The 3-(4-hydroxybenzyl)-2-[4-[2-(1-pyrrolidinyl)
ethoxy]phenyl]benzo[b]thiophene may be obtained as follows.
A. 2-(4-Hydroxyphenyl)benzo[b]thiophen-3-yl 4-Methoxy-
phenyl Retone.
OMe
vH
To a solution of 10.0 g (26.7 mmol) of 2-(4-methoxy-
phenyl)benzo[b]thiophen-3-yl 4-methoxyphenyl ketone in 400
mL of CH2C12 at -10 °C was added dropwise 107 mL of a 1.0 M
solution of BBr3 in CH2C12. After complete addition, the
reaction was stirred at -10 °C for 1 h and was quenched by
the careful addition of 75 mL of MeOH. The mixture was
allowed to warm to room temperature and was stirred at
ambient temperature for 2 h. Evaporation of the volatiles
in vacuo afforded a deep red oil which was taken up in 250
mL of EtOAc. The solution was then washed sequentially with
saturated aq NaHC03 (2 x 200 mL), H20 (200 mL) and brine
(200 mL), dried over Na2S04, and concentrated in vacuo to
give 9.85 g of a red oil which was purified by flash
chromatography (Si02;.25% EtOAc in hexanes) to afford 8.69 g
(24.1 mmol; 900) of the title compound as a light yellow
solid.
FDMS 360 (M+; 100).
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_98-
B. 2- [4- [2- (1-Pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophen-
3-yl 4-Methoxyphenyl Ketone.
OMe
~ N
J
By essentially following the procedure detailed in
Example 1, Part E, using 1-(2-chloroethyl)pyrrolidine
hydrochloride as the alkylating agent and an extra
equivalent of base, the title compound was prepared from
2-(4-hydroxyphenyl)benzo[b]thiophen-3-yl 4-methoxyphenyl
ketone (Part A) as an oil in 80% yield following flash
chromatography (Si02; 2.5o MeOH in CH2C12).
FDMS 457 (M+; 100); Anal. Calcd for C28H27N03S: C, 73.49;
H, 5.95; N; 3.06. Found: C, 73.19 ; H, 5.96; N, 3.02.
C. 2- [4- I2- (1-Pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophen-
3-yl 4-Hydroxyphenyl Ketone.
OH
~ N
2o J
A solution of 1.90 g (4.15 mmol) of 2-[4-[2-(1-pyrro-
lidinyl)ethoxy]phenyl]benzo[b]thiophen-3-yl 4-methoxyphenyl
ketone (Part B) in 50 mL of DMF was treated with 0.7 g (8.30
mmol) of sodium thioethoxide at 80 °C for 1 h. The mixture
was cooled, filtered, and concentrated in vacuo. ThP
residue was taken up in 100 mL of CH2C12 and was transferred
to a separatory funnel containing 200 mL of H20. The
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
_99_
aqueous layer was adjusted to pH 8 with 5.0 N aq HC1 and the
contents were shaken well. The two layers were separated
and the aqueous layer was extracted with EtOAc. The
combined organic layers were dried over K2C03 and evaporated
to give a yellow solid which was triturated with EtOAc to
afford 1.40 g of the title compound as a yellow solid.
FDMS 443 (M+; 100).
D. 3- (4-Hydroxybenzyl) -2- [4- [2- (1-pyrrolidinyl) ethoxy] -
phenyl] benzo [b] thiophene .
OH
~ N
J
By essentially following the procedures detailed in
Example 1, Part D, the title compound was prepared in 51%
yield as a white solid.
FDMS 429 (M'~; 100) .
Example 28
Preparation of 3- [4- (2-Methoxy-2-oxoethoxy)benzoyl] -2- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene
Hydrochloride.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-100-
The title compound was prepared following the procedure
of Example 27 and utilizing methyl a-bromoacetate and
3- (4-hydroxybenzoyl) -2- [4- [2- (1-pyrrolidinyl) ethoxy] phenyl] -
benzo [b] thiophene .
FDMS m/ a 515 ( M+ ) ;
Analysis for C30H29N05S~HC1:
Calcd: C, 65.27; H, 5.48; N, 2.54;
Found: C, 62.82; H, 5.49; N, 2.58.
Example 29
Preparation of 3- [4- (2-Hydroxyethoxy)benzyl] -2- [4- [2-
(1-pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophene.
H
To the product (1 g, 1.94 mmol) of Example 28 dissolved
in anhydrous THF (80 mL) was added LAH (0.47 g, 12.4 mmol)
at 0-5° C under nitrogen. The reaction mixture was stirred
for 2 hours and quenched with ice-cold NaOH (0.5 M)
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-101-
solution. The organic layer was extracted with ethyl
acetate, combined, dried and concentrated in vacuo. To this
residue (0.88 g, 1.8 mmol) dissolved in dichloromethane
("50 mL) was added triethylsilane (1.73 mL, 10.8 mmol) and
TFA (0.42 mL, 5.4 mmol). The reaction mixture was stirred
for 1.5 hours before it was washed with dilute NaOH solution
and brine until neutral. The combined organic layers were
dried with Na2S04 and concentrated. The residue was
purified by column chromatography (20% CH30H in
dichloromethane) to yield 0.53 g (63a) of title compound.
FDMS m/e 474.3 (M+);
Analysis for C2gH31N03S:
Calcd: C, 73.54; H, 6.60; N, 2.96;
Found: C, 71.32; H, 6.29; N, 2.93.
Example 30
Preparation of 3- [4- [3- (1H-Tetrazol-5-yl)propyloxy] benzyl] -
2- [4- [2- (1-pyrrolidinyl) ethoxy] phenyl] benzo [b] thiophene
Trifluoroacetic Acid Salt.
O
F
HO
F
F
A. 3- [4- (3-Cyanopropyloxy) benzyl] -2- [4- [2-
(1-pyrrolidinyl)ethoxy)phenyl]benzo[b]thiophene.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-102-
N
To a stirred solution of 3- (4-hydroxybenzyl) -2- [4- [2-
(1-pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene (0.9 g, 2.09
mmol) in anhydrous DMF (50 mL) was added NaH (0.5g, 60o in
mineral oil, 12.5 mmol) under nitrogen. The resultant
mixture was stirred for 10-20 min, followed by the addition
of 4-bromobutyronitrile and further stirring for 1.5 hours.
The mixture was diluted with EtOAc and ice water. The
organic phase was washed with brine, dried with Na2S04 and
concentrated in vacuum. The resulting crude product was
purified on a silica column (5o methanol in CH2C12) to give
0.75 g (62%) of the title compound as a light yellow oil.
B. 3- [4- [3- (1H-Tetrazol-5-yl)propyloxy]benzyl] -2- [4- [2- (1-
pyrrolidinyl)ethoxy]phenyl]benzo[b]thiophene Trifluoroacetic
Acid Salt.
To a stirred solution of the product from Part A (133
mg, 0.27 mmol) in dichloromethane (20 mL) was added Bu3SnN3
(1.5 mL, 5.5 mmol). Dichloromethane was removed under
reduced pressure and the reaction mixture was stirred under
nitrogen at 95 ~C overnight. The reaction mixture was
cooled to room temperature and diluted with CH3CN (10-20 mL)
and THF (2 mL) and then acidified with HOAc (3 mL). After
being stirred for 3.5 hour, the reaction mixture was washed
with hexane, concentrated in vacuo, and diluted with EtOAc
and brine. The combined organics were dried with Na2S04 and
concentrated. The residue was purified by reverse phase
CA 02287901 1999-10-29
WO 98!48798 PCT/US98/08700
-103-
HPLC (gradient 5-70% TFA in CH3CN) to afford 107 mg (74%) of
the TFA salt as a white solid.
FDMS m/e 540.4 (M+);
Analysis for C31H33N502S'C2HF302~1.5H20:
Calcd: C, 58.31; H, 5.34; N, 10.30;
Found: C, 58.21; H, 5.25; N, 10.29.
Example 31
Preparation of 3-[4-(3-Methyl-4-methoxy-4-oxobutyloxy)-
benzyl] -2- [4- [2- {1-pyrrolidinyl) ethoxy] phenyl] benzo [b] -
thiophene Hydrochloride.
The title compound was prepared following the
procedures of Example 27 utilizing methyl 2-methyl-4-
bromobutyrate.
FDMS m/e 544 (M+);
Analysis for C31H37N04S~HC1:
Calcd: C, 68.32; H, 6.60; N, 2.41;
Found: C, 65.47; H, 6.57; N, 2.43.
Example 32
Preparation of 3-[4-(3-Methyl-4-hydroxy-4-oxobutyloxy)-
benzyl] -2- [4- [2- (1-pyrrolidinyl) ethoxy] phenyl] benzo [b] -
thiophene.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-104-
The hydrolysis of the product from Example 31 was
carried out at room temperature by NaOH solution using
acetone and methanol as the solvent.
FDMS m/e 530 (M+) ;
Analysis for C3pH35NO4S:
Calcd: C, 72.56; H, 6.66; N, 2.64;
Found: C, 65.00; H, 6.42; N, 2.31.
Example 33
Preparation of 4-[4-[6-Hydroxy-3-[3-methoxy-4-(1-pyrroli-
dinylmethyl)benzyl]benzo[b]thiophen-2-yl]phenoxy]butanol
Oxalate.
r'2H2~4
HO
OH
A. 4-[4-[6-Benzyloxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl]benzo[b]thiophen-2-yl]phenoxy]butanoic Acid
Methyl Ester.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-105-
Bn0
o-
4-[6-Benzyloxy-3-[3-methoxy-4-{1-pyrrolidinylmethyl)-
benzyl]benzo[b]thiophen-2-yl]phenol (0.10 g; 0.19 mmol),
4-chlorobutyric acid methyl ester (27 mL; 0.22 mmol) and
Cs2C03 (0.43 g; 1.31 mmol) were combined in 2 mL of DMF and
heated in an oil bath maintained at 80° C for 3 h. After
cooling to room temperature, water (30 mL) was added, and
extraction was carried out with EtOAc (4 x 25 mL). The
combined organics were washed with brine and dried by
passage through Na2S04. Purification was effected by flash
chromatography on silica gel, eluting with
EtOAc(100-90%)/Et3N(0-5%)/MeOH(0-5%). The title product was
obtained as a colorless oil (92 mg, 78%).
1H NMR CDC13 8 7.41 (m, 9H), 7.20 (d, J=7.6 Hz, 1H), 6.99
(dd, J=2.2, 8.8 Hz, 1H), 6.92 (d, J=8.7 Hz, 2H), 6.70 (d,
J=7.7 Hz, 1H), 6.67 (s, 1H), 5.14 {s, 2H), 4.21(s, 2H), 4.05
(t, J=6.0 Hz, 2H), 3.71 (s, 6H), 3.62 (s, 2H), 2.56 {m, 6H),
2.15 (m, 2H), 1.78 (br s, 4H). FDMS 636.2 (M+1).
B. 4-[4-[6-Benzyloxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl]benzo[b]thiophen-2-yl)phenoxy]butanol.
CA 02287901 1999-10-29
WO 98/48798 PCT1US98/08700
-106-
Bn0
OH
The 4-[4-[6-benzyloxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl) benzyl] benzo [b] thiophen-2-yl] phenoxy] butanoic acid
methyl ester prepared in Part A (91 mg; 0.14 mmol) was
dissolved in anhydrous THF under argon atmosphere. LAH
(10 mg; 0.29 mmol) was added. The mixture was stirred at
room temperature for 3 h before it was hydrolyzed by
addition of 2 drops of water, 2 drops of 5 M NaOH, and six
drops of water. Additional water (25 mL) was added, and
extraction was carried out with CH2C12. The combined
organics were dried by passage through Na2S04. Purification
was effected by flash chromatography on silica gel, eluting
with EtOAc(100-90o)/Et3N(0-5o)/MeOH(0-5%). The title
product was obtained as a colorless oil (74 mg, 850).
1H NMR CDC13 b 7.41 (m, lOH), 7.10 (d, J=7.6 Hz, 1H), 7.00
(dd, J=7.7, 7. 10 , ), 6.93 (d, J=8.7 Hz, 2H), 6.72 (d,
Hz 1H
J=7.8 Hz, 1H), 6.68 (s, 1H), 5.14 (s, 2H), 4.27(s, 2H), 4.04
(t, J=6.1 Hz, 2H), 3.72(m, 5H), 3.65 (s, 2H), 2.59 (br s,
4H), 1.92 (m, 4H), 1.80(br s, 4H). FDMS 608 (M+1).
C. 4-[4-[6-Hydroxy-3-[3-methoxy-4-(1-pyrrolidinylmethyl)-
benzyl]benzo[b]thiophen-2-yl]phenoxy]butanol Oxalate.
4- [4- [6-Benzyloxy-3- [3-methoxy-4- (1-pyrrolidinyl-
methyl) benzyl] benzo [b] thiophen-2-yl] phenoxy] butanol prepared
in Part B (74 mg; 0.12 mmol) was combined with 30 mg of 10%
palladium on charcoal catalyst and 3 mL of 25o aqueous
NH402CH in 3 mL of THF/MeOH (1:1). The mixture was stirred
CA 02287901 1999-10-29
WO 98/48798 PCT/iJS98/08700
-107-
at room temperature overnight. The product was isolated by
filtration through diatomaceous earth and concentration
under reduced pressure. Purification was effected by MPLC
on silica gel eluting with EtOAc(100-90%)/Et3N(0-5o)/MeOH(0-
5%). Conversion to the oxalate was effected in the usual
way.
1H NMR MeOH-d4 8 7.36 (m, 3H), 7.20 (d, J=2.2 Hz, 1H), 7.16
(d, J=7.7 Hz, 1H), 6.93 (d, J=8.6 Hz, 2H), 6.78 (m, 2H),
6.71 (d, J=7.9 Hz, 1H), 4.20 (s, 2H), 4.01(t, J=6.3 Hz, 2H),
3.93 (s, 2H), 3.72 (s, 3H), 3.62 (t, J=6.3 Hz, 2H), 2.90 (m,
4H), 1.90 (m, 6H), 1.70 (m, 2H). FDMS 518 (M+1 for free
base). Anal calc'd for C31H35N04S~C2H204: C, 65.24; H,
6.10; N; 2.31. Found: C, 64.98; H, 6.42; N, 2.34.
Example 34
Preparation of 5- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] -
benzo[b]thiophen-2-yl]phenoxy]pentanol Oxalate.
C2H20a
OH
A. 5- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenoxy]pentanoic Acid Ethyl Ester.
O
O
S
O
O
CA 02287901 1999-10-29
WO 98/48798 PCTJUS98/08700
-108-
4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenol (0.25 g; 0.58 mmol), ethyl
5-bromovalerate (0.19 mL; 1.20 mmol) and Cs2C03 (2.3 g; 7.06
mmol) were combined in 5 mL of DMF in a flame-dried, argon-
filled flask. The resultant mixture was stirred at room
temperature for 2 h. Water (50 mL) was added, and the
mixture extracted with EtOAc (4 x 25 mL). The combined
organics were washed with brine and dried by passage through
MgS04. The product (78 mg; 25%) was isolated by flash
chromatography on silica gel, eluting with EtOAc(100-950)/_
Et3N(0-5%) .
1H NMR CDC13 8 7.85 (d, J=8.6 Hz, 1H), 7.51 (m, 1H), 7.43
(d, J=8.7 Hz, 2H), 7.31 (m, 2H), 7.06 (d, J=8.5 Hz, 2H),
6.93 (d, J=8.6 Hz, 2H), 6.83 (d, J=8.5 Hz, 2H), 4.22 (s,
2H), 4.15 (q, J=7.2 Hz, 2H), 4.08 (t, J=6.0 Hz, 2H), 4.02
(br s, 2H), 2.90 (t, J=6.0 Hz, 2H), 2.62 (br s, 4H), 2.41
(br s, 2H), 1.83 (m, 8H), 1.28 (t, J=7.1 Hz, 3H). FDMS 557
(M+1) .
B. 5- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenoxy]pentanol Oxalate.
5- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenoxy]pentanoic acid ethyl ester prepared in
part A (78 mg; 0.14 mmol) was dissolved in 3 mL of anhydrous
THF under an argon atmosphere, then LAH (10 mg; 0.29 mmol)
was added. The resultant mixture was stirred at room
temperature for 3 h. To the reaction was added 1 drop of
water, 1 drop of 5 M NaOH, and 3 drops of water. The
mixture was stirred at room temperature for 45 min, then
water (25 mL) was added. Extraction was carried out with
EtOAc (4 x 25 mL). The combined organics were dried by
passage through Na2S04. The product was isolated as a
colorless oil (49 mg; 660) by flash chromatography on silica
gel, eluting with EtOAc(10-90o)/Et3N(0-5o)/MeOH(0-5%).
Conversion to the oxalate was effected in the usual way.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98l08700
-109-
1H NMR CDC13 b 7. 84 (m, 1H) , 7. 52 (m, 1H) , 7.43 (m, 2H) ,
7.30 (m, 2H), 7.07 (d, J=9.0 Hz, 2H), 6.91 (d, J=8.7 Hz,
2H), 6.83 (d, J=8.5 Hz, 2H), 4.22 (s, 2H), 4.09 (t, J=6.0
Hz, 2H), 4.01 (t, J=6.4 Hz, 2H), 3.70 (t, J=6.2 Hz, 2H),
2.89 (t, J=6.0 Hz, 2H), 2.65 (br s, 4H), 1.83 (m, 6H), 1.64
(m, 4H). FDMS 516 (M+1 for free base); Anal calc'd for
C32H37N03S~C2H204~1/2H20: C, 66.43; H, 6.56; N; 2.28. Found:
C, 66.08; H, 6.32; N, 2.16.
Example 35
Preparation of 3- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] -
benzo[b]thiophen-2-yl]phenoxy]propanol Oxalate.
r
N
p ~ C2H20a
OH
3-Bromopropanol (1.3 mL; 1.44 mmol) was combined with
2,6-lutidine (4.2 mL; 36.0 mmol) in CH2C12 (25 mL) in a
flame-dried, argon-filled flask. The mixture was cooled to
0 °C and triisopropylsilyl triflate (5 mL; 18.7 mmol) was
added. After standing at room temperature for 1.5 h, water
was added and extraction was carried out with EtOAc. The
combined organics were dried by passage through Na2S04.
Concentration under reduced pressure left the 3-bromo-1-
triisopropylsilyloxypropane, which was used without further
purification.
4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] thio-
phen-2-yl]phenol (0.25 g; 0.58 mmol), 0.21 g (0.70 mmol) of
the triisopropylsilyl ether prepared above and Cs2C03 (1.33
g; 4.07 mmol) were combined in 5 mL of DMF in a flame-dried,
argon-filled flask and heated in an oil bath maintained at
70 °C for 2 h. After cooling to room temperature, water was
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08'700
-110-
added (25 mL) and extraction was carried out with EtOAc (4 x
25 mL). The combined organics were dried by passage through
Na2S04. The triisopropylsilyl protecting group was removed
by stirring with an excess of tetrabutylammonium fluoride in
THF at room temperature for 0.5 h. The product was isolated
as a colorless oil (165 mg; 58%) by flash chromatography on
silica gel, eluting with EtOAc(10-90%)/Et3N(0-So)/MeOH(0-
5%). Conversion to the oxalate was effected in the usual
way.
1H NMR CDC13 8 7.84 (m, 1H), 7.52 (m, 1H), 7.43 (d, J=8.6
Hz, 2H), 7.30 (m, 2H), 7.05 (d, J=8.5 Hz, 2H), 6.95 (d,
J=8.6 Hz, 2H), 6.82 (d, J=8.5 Hz, 2H), 4.21 (s, 2H), 4.15
(t, J=5.9 H2, 2H), 4.08 (t, J=6.0 Hz, 2H), 3.88 (t, J=5.9
Hz, 2H), 2.90 (t, J=5.9 Hz, 2H), 2.64 (br s, 4H), 2.07 (m,
2H), 1.81 (m, 4H). FDMS 488 (M+1 for free base). Anal
calc'd for C3pH33N03S~C2H204: C, 66.55; H, 6.07; N; 2.36.
Found: C, 66.79; H, 6.23; N, 2.36.
Example 36
Preparation of 4- [4- [3- [3-Methoxy-4- (1-pyrrolidinylmethyl) -
benzyl]benzo[b]thiophen-2-yl]phenoxy]butanol Oxalate.
O
C'2H2~4
J
A. 4- [4- [3- [3-Methoxy-4- (1-pyrrolidinylmethyl)benzyl] -
benzo[b]thiophen-2-yl]phenoxy]butanoic Acid Methyl Ester.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-111-
J
0
o_
Essentially by application of the procedure of
Example 34, Part A, using 4-[3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl]benzo[b]thiophen-2-yl]phenol and 4-bromo-
butyric acid methyl ester as the starting materials, the
product was obtained in 58o yield.
1H NMR CDC13 7.84 (m, 1H), 7.56 (m, 1H), 7.45 (d,
8
J=8.6 Hz, 2H), 7.30 (m, 2H), 7.20 (d, J=7.6 Hz,lH), 6.92 (d,
J=8.6 Hz, 2H), 6.70 (d, J=7.9 Hz, 1H), 6.67 (s, 1H), 4.26
(s, 2H), 4.05 (t, J=6.1Hz, 2H), 3.71 (s, 3H), 3.70 (s, 3H),
3.63 (s, 2H), 2.56 (br s, 6H), 15 (m, 2H), 1.78 (br s,
2.
4H). FDMS 529 (M+1).
8. 4-[4-[3-[3-Methoxy-4-(1-pyrrolidinylmethyl)benzyl]-
benzo[b]thiophen-2-yl]phenoxy]butanol Oxalate.
Essentially by application of the procedure of Example
34, Part B, using 4-[4-[3-[3-methoxy-4-(1-pyrrolidinyl-
methyl) benzyl] benzo [b] thiophen-2-yl] phenoxy] butanoic acid
methyl ester prepared in Part A as the starting material,
the desired compound was obtained in 82a yield. Conversion
to the oxalate was effected by the usual procedure.
1H 7.84 1H), 7.56 (m, 1H), 7.44 (d, J=8.7
NMR CDC13 (m,
8
Hz, 2H), 7.30 (m, 2H), 7.20 (d, J=7.6 Hz,lH), 6.94 (d, J=8.8
Hz, 2H), 6.68 (d, J=8.0Hz, 1H), 6.67 (s, 1H), 4.26 (s, 2H),
4.04 (t, J=6.1 Hz, 2H), 3.74 (t, J=6.3 Hz, 2H), 3.70 {s,
3H), 3.63 (s, 2H),2.58 (br s, 4H), 1.91 (m, 4H), 1.77 (br
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-112-
s, 4H). FDMS 502 (M+1). Anal calc'd for C31H35N03S~C2H204:
C, 67.00; H, 6.26; N; 2.09. Found: C, 66.76; H, 6.05; N,
2.09.
Example 37
Preparation of 3- [4- [2- (1-Pyrrolidinyl) ethoxy]benzyl] -2- [4-
[3 - ( 5 - tetrazolyl ) propoxy] phenyl] benzo [b] thiophene .
O
' N
O
S
NON
!!
N~N
H
4- [4- [3- [4- [2- (1-Pyrrolidinyl) ethoxy] benzyl] benzo [b] -
thiophen-2-yl]phenoxy]butyronitrile (0.104 g; 0.21 mmol) and
tri-n-butyltin azide (0.12 mL; 0.42 mmol) were combined in
1.0 mL of ethyleneglycol diethyl ether, heated in an oil
bath maintained at 115 °C overnight, and cooled to room
temperature. A mixture was prepared of 45 mL of water, 5 mL
of conc HC1 and 50 mL of hexane. The reaction mixture was
poured into this mixture with rapid stirring, and washed in
with a small amount of EtOAc. After stirring for 1.5 h, the
product was isolated by suction filtration and washed with
fresh water. Purification was effected by HPLC on a [Vydac]
Clg reversed-phase column, eluting with H20/TFA/CH3CN
(94:1:5->39:1:60). Pure tetrazole (27.3 mg; 240) was
obtained.
1H NMR DMSO-d6 8 7.84 (m, 1H), 7.52 (m, 1H), 7.43 (d, J=8.6
Hz, 2H), 7.30 (m, 2H), 7.05 (d, J=8.5 Hz, 4H), 6.82 (d,
J=8.5 Hz, 2H), 4.21 (s, 2H), 4.17 (s, 2H), 4.08 (t, J=6.0
Hz, 2H), 3.52 (t, J=5.9 Hz, 2H), 3.05 (t, J=5.9 Hz, 2H),
CA 02287901 1999-10-29
WO 98!48798 PCT/US98/08700
-113-
2.50 (br s, 4H), 2.15 (m, 2H), 1.81 (br s, 4H). FAB+ MS
540.2 (M+1) .
Example 38
Preparation of Methyl 4-[4-[5-Methoxy-3-[3-methoxy-4-(1-
pyrrolidinylmethyl) benzyl] benzo [b] thiophen-2-yl] phenoxy] -
butyrate Oxalate.
-(COZH)z
O
,O
O~
A. 4-(5-Methoxybenzo[b]thiophen-2-yl)phenol.
\ _
off
s
A mixture of 3.43 g (16.5 mmol) of 5-methoxybenzo[b]-
thiophene-2-boronic acid, 6.21 g (16.5 mmol) of
4-(triisopropylsilyloxy)iodobenzene, 952.3 mg (0.82 mmol) of
Pd(PPh3)4 and 16 mL of 2.0 M Na2C03 in 80 mL of distilled
THF was heated at reflux for 19 h. The mixture was filtered
through a diatomaceous earth pad to remove the Pd catalyst
with thorough EtOAc, THF, and H20 rinse. The layers were
separated and the organic layer was washed with 200 mL of
brine. The aqueous layers were back extracted with 2 x 500
mL of EtOAc. Combined organic layers were dried over MgS04,
concentrated, and purified by PrepLC 500A with 0-20o Et20-
hexanes as eluent to afford 2.22 g (530) of the title
compound along with 314 mg (4.60) of its TIPS ether.
FDMS 256.1 (M+); Anal. Calcd for C15H1202S~ C, 70.29; H,
4.72. Found: C, 70.20; H, 4.61.
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-114-
B. Methyl 4-[4-(5-Methoxybenzo[b]thiophen-2-yl)phenoxy]-
butyrate.
O
O~~Di
g~
A mixture of 549.6 mg (2.14 mmol) of the phenol
(Part A), 2.09 g (6.4 mmol) of Cs2C03, and 0.32 mL
(2.57 mmol) of methyl 4-chlorobutyrate in 5.0 mL of
anhydrous DMF was heated at 85-90 °C (bath temperature) for
2 h. The mixture was diluted with EtOAc to ca. 100 mL and
filtered. The filtrate was washed with 100 mL of saturated
aqueous NH4C1, H20 (2x) and saturated aqueous NaHC03. The
aqueous layers were back extracted with 2 x 100 mL of EtOAc.
Combined organic layers were dried over MgS04 and
concentrated to yield 756.9 mg (990) of the clean crude
product.
1H NMR 8 7.66 (d, J = 8.8 Hz, 1H), 7.61 (d, J =
(CDC13) 8.6
Hz, 2H), 7.35 (s, 1H),7.21 {d, J = 2.3 Hz, 1H), 6.94 {m,
1H), 6.93 (d, J = 8.6 Hz, 2H), 4.05 (t, J = 6.0 Hz, 2H),
3.87 (s, 3H), 3.70 3H), 2.55 (t, J = 7.2 Hz, 2H), 2.14
(s,
(m, 2H) .
C. Methyl 4-[4-[5-Methoxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzoyl]benzo[b]thiophen-2-yl]phenoxy]butyrate.
O
o~
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-115-
Friedel-Crafts acylation of 852 mg (2.4 mmol) of the
above benzo[b]thiophene (Part B) with an equimolar amount of
3-methoxy-4-(1-pyrrolidinylmethyl)benzoyl chloride as
previously described afforded 675.5 mg (490) of the title
- 5 compound along with 331.0 mg (18%) of 3,6-diacylated product
and 245.1 mg {29%) of recovered starting benzo[b]thiophene.
FDMS 574 (M+1); Anal. Calcd for C33H35N06S: C, 69.9; H,
6.15; N, 2.44. Found: C, 69.19; H, 6.01; N, 2.38.
D. Methyl 4-[4-[5-Methoxy-3-[3-methoxy-4-(1-pyrrolidinyl-
methyl)benzyl]benzo[bJthiophen-2-yl]phenoxy]butyrate
Oxalate.
The title compound was prepared in 56% yield in three
steps from the ketone (Part C): (1) reduction of 224.7 mg
(0.39 mmol) of the ketone (Part 3) with 37.0 mg (0.98 mmol)
of NaBH4 in the presence of 218.9 mg (0.59 mmol) of
CeCl3-7H20 in 1.5 mL of MeOH overnight; (2) dehydroxylation
with Et3SiH/TFA in CH2C12 at 0 °C for 1 h; followed by (3)
oxalate formation as previously described.
FDMS 559.1 {M+); Anal. Calcd for
C33H37N05S-0.9C2H204-0.3C4H802: C, 64.81; H, 6.22; N, 2.10.
Found: C, 64.77; H, 6.61; N, 2.08.
Example 39
Preparation of 4-[4-[5-Methoxy-3-[3-methoxy-4-(1-pyrroli-
dinylmethyl) benzyl] benzo [b] thiophen-2-yl] phenoxy] butanol
Oxalate.
-(COZH)z
~O
~~~OH
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-116-
The title compound was prepared in 27% yield in three
steps from LAH reduction of methyl 4-[4-[5-methoxy-3-
[3-methoxy-4-(1-pyrrolidinylmethyl)benzoyl]benzo[b]thiophen-
2-yl]phenoxy]butyrate (Part C of Example 38) in THF at 0-10
°C for 1 h, followed by dehydroxylation with Et3SiH/TFA in
CH2C12 and oxalate formation as previously described.
FDMS 531.2 (M+); Anal. Calcd for C34H3gNO8S~0.7C4H802: C,
64.68; H, 6.58; N, 2.05. Found: C, 64.35; H, 6.76; N,
2.21.
Example 40
Preparation of 2- [4- (3-Ethoxy-3-oxopropyl)phenyl] -3- [4- [2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
O
\ / ~"
w \
/ o
o
A. 2- (4-Formylphenyl) -3- [4- [2- (1-pyrrolidinyl) ethoxy] -
2 0 benzyl] benzo [b] thiophene .
O
\ / ~"
i S ~ / o
H
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-117-
To a solution of Mg0 (0.385 mg, 16.08 mmol), in THF
(1 mL), was added p-bromobenzaldehyde dimethylacetal
(3.71 g, 16.08 mmol, prepared from p-bromobenzaldehyde and
MeOH following standard procedures) and the mixture stirred
for 1 h. Additional THF (15 mL) was added to the Grignard
reagent and then the solution transferred to a flask
containing 2-dimethylaminobenzo[b]thiophene-3-yl
4-[2-(1-pyrrolidinyl)ethoxy]phenyl ketone (3.04 g,
8.04 mmol) in THF (15 mL). The mixture was stirred at room
temperature for 2 h, then quenched by the addition of
saturated NH4C1, H20, and extracted into EtOAc. The organic
extracts were concentrated in vacuo, and the resulting
residue purified by flash chromatography (Si02, 2o MeOH in
CHC13). To LAH (47 mg, 1.25 mmol) in THF (1 mL) was added
the above ketone (585 mg, 1.25 mmol) in THF (4 mL). The
mixture was stirred at room temperature for 1 h and then
quenched by the sequential addition of 50 ~L of H20, 50 ~L
of 15% NaOH, and 150 ~tl H20. The resulting aluminum salts
were removed by filtering over a pad of diatomaceous earth
and the filtrate concentrated in vacuo. The resulting
alcohol was then taken up in 80o HOAc, stirred for 2 h and
then concentrated in vacuo. The residue was dissolved in
CH2C12, cooled to 0 oC and treated with Et3SiH (7
equivalents). TFA (10 equivalents) was then added and the
reaction mixture stirred at 0 oC for 1 minute, and then the
reaction was quenched by the addition of saturated NaHC03.
Material was then diluted 10 fold with EtOAc, the organics
washed with H20, and concentrated in vacuo. The residue was
purified by flash chromatography (Si02, 1% MeOH in CHC13
with 1% Et3N v/v added).
FDMS 441.9 (M+); Anal. Calcd. For C28H27N02S~0.5 H20: C,
74.63; H, 6.26; N, 3.11. Found: C, 74.86; H, 6.17; N, 3.08.
B. 2- [4- (3-Ethoxy-3-oxoprop-1-enyl)phenyl] -3- (4- [2
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
CA 02287901 1999-10-29
WO 98!48798 PCT/US98/08700
-118-
O~
N
O
To a solution of NaH (12 mg, 0.51 mmol), in THF (1 mL)
and under N2, was added triethyl phosphonoacetate (58 ~L,
0.292 mmol) and the mixture stirred at room temperature for
30 minutes. To this ylide was then added the above
benzaldehyde (Part A, 129 mg, 0.292 mmol) in THF (0.5 mL),
and the mixture stirred at room temperature for 30 min.
After diluting with EtOAc (50 fold), the organics were
washed with saturated NaHC03, H20, brine, and concentrated
in vacuo. Product was purified by flash chromatography
(Si02, 5% MeOH in CHC13); yielding 130 mg of desired
material.
1H NMR (CDC13) d 7.86 (d, J=7.1 Hz, 1H), 7.71 (d, J=15.9 Hz,
1H), 7.54 (m, 5H), 7.35(m, 2H), 7.06 (d, J=8.5 Hz, 2H), 6.84
(d, J=6.8 Hz, 2H), 6.47 (d, J=15.9 Hz, 1H), 4.29 (q, J=7.1,
14.3 Hz, 2H), 4.26 (s, 2H), 4.09 (t, J=6.0 Hz, 2H), 2.90 (t,
J=6.0 Hz, 2H), 2.63 (m, 4H), 1.82 (m, 4H), 1.36 (t, J=7.1
Hz, 3H); FDMS 512 (M+).
C. 2- [4- (3-Ethoxy-3-oxopropyl)phenyl] -3- [4- [2-
(1-pyrrolidinyl) ethoxy] benzyl] benzo [b] thiophene.
To a solution of the above unsaturated ester (Part B,
110 mg, 0.215 mmol) in EtOH (5 mL) was added 5o Pd/C
(110 mg) and the mixture rapidly stirred under H2 (1 atm)
for 10 h. The catalyst was then removed by filtering over a
pad of diatomaceous earth, the filtrate concentrated in
vacuo, and the material purified by flash chromatography
CA 02287901 1999-10-29
WO 98/48798 PCT/US98/08700
-119-
(Si02, 10% MeOH in CHC13), yielding 51 mg of desired
product.
FDMS 513 (M+); Anal. Calcd. for C32H35N03S: C, 74.82; H,
6.87; N, 2.73; Found: C, 74.87; H, 6.85; N, 2.89.
