U.S. patent application number 10/826099 was filed with the patent office on 2004-10-07 for efficient process for the preparation of a factor xa inhibitor.
Invention is credited to Anzalone, Luigi, Jin, Fuqiang, Li, Hui-Yin, Meloni, David J., Rossano, Lucius T., Smyser, Thomas E., Sun, Jung-Hui, Teleha, Christopher A., Zhou, Jiacheng.
Application Number | 20040198787 10/826099 |
Document ID | / |
Family ID | 22882119 |
Filed Date | 2004-10-07 |
United States Patent
Application |
20040198787 |
Kind Code |
A1 |
Li, Hui-Yin ; et
al. |
October 7, 2004 |
Efficient process for the preparation of a factor Xa inhibitor
Abstract
The present invention relates to the process for the preparation
of the compound of Formula I: 1 from its corresponding
3-cyano-4-fluorophenyl-pyrazole and intermediates useful
therein.
Inventors: |
Li, Hui-Yin; (Hockessin,
DE) ; Anzalone, Luigi; (West Chester, PA) ;
Jin, Fuqiang; (Lawrenceville, NJ) ; Meloni, David
J.; (Bear, DE) ; Sun, Jung-Hui; (Hockessin,
DE) ; Rossano, Lucius T.; (Landenberg, PA) ;
Teleha, Christopher A.; (Bear, DE) ; Zhou,
Jiacheng; (Hockessin, DE) ; Smyser, Thomas E.;
(Wilmington, DE) |
Correspondence
Address: |
STEPHEN B. DAVIS
BRISTOL-MYERS SQUIBB COMPANY
PATENT DEPARTMENT
P O BOX 4000
PRINCETON
NJ
08543-4000
US
|
Family ID: |
22882119 |
Appl. No.: |
10/826099 |
Filed: |
April 15, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10826099 |
Apr 15, 2004 |
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10431265 |
May 7, 2003 |
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6747158 |
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10431265 |
May 7, 2003 |
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09960040 |
Sep 21, 2001 |
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6667332 |
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60234622 |
Sep 22, 2000 |
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Current U.S.
Class: |
514/379 ;
548/241 |
Current CPC
Class: |
C07D 403/12 20130101;
C07D 413/14 20130101; A61P 7/02 20180101 |
Class at
Publication: |
514/379 ;
548/241 |
International
Class: |
A61K 031/42; C07D
413/14 |
Claims
1-16. (canceled)
17. A process according to claim 1, wherein the compound of Formula
IVa is prepared by the process, comprising: 17(b) coupling
compounds of Formulas II and III to form a compound of Formula
IVa.
18. A process according to claim 17, wherein the compound of
Formula IVa is used without purification in (c).
19. A process according to claim 17, wherein (b) is performed by
contacting a compound of Formula II with an acid activator, in a
solvent and a first base, followed by contacting the resulting
solution with a compound of Formula III.
20. A process according to claim 19, wherein (b) is performed by
contacting a compound of Formula II with oxalyl chloride in
acetonitrile and pyridine, followed by contacting the resulting
solution with a compound of Formula III.
21. A process according to claim 20, wherein after a compound of
Formula II has been contacted with a compound of Formula III, a
second base is added to the reaction solution.
22. A process according to claim 21, wherein the second base is
diisopropylethylamine.
23-27. (canceled)
29. A compound of Formula Va: 18or a pharmaceutically acceptable
salt form thereof.
30-31. (canceled)
Description
FIELD OF THE INVENTION
[0001] This invention relates generally to an efficient process for
the preparation of a benzisoxazolyl-pyrazole.
Benzisoxazolyl-pyrazoles are useful as factor Xa inhibitors.
BACKGROUND OF THE INVENTION
[0002] Factor Xa inhibitors like those of Formula Ia shown below:
2
[0003] WO98/57951 describes the synthesis of the compound of
Formula Ia, as its trifluoroacetic acid salt, as follows: 3
[0004] In the above procedure, the pyrazole carboxylic acid and
aniline are coupled and isolated as a free base. The
3-cyano-4-fluorophenyl group of the resulting product is then
converted to 1-aminobenzisoxazole. One problem with this procedure
is that the acid-aniline coupling product is difficult to purify. A
second problem is that the conversion to the 1-aminobenzisoxazole
moiety requires the presence of a strong, expensive base such as
KOt-Bu.
[0005] It can be seen that the preparation of a compound of Formula
I is difficult. Thus, it is desirable to find an efficient
synthesis of such a compound.
SUMMARY OF THE INVENTION
[0006] Accordingly, one object of the present invention is to
provide a novel process for preparing a compound of Formula I.
[0007] It is another object of the present invention to provide
intermediates that are useful in preparing a compound of Formula
I.
[0008] It is another object of the present invention to provide
novel salt, crystalline, and solvent forms of Formula I.
[0009] It is another object of the present invention to provide
pharmaceutical compositions comprising a pharmaceutically
acceptable carrier and a therapeutically effective amount of at
least one of the compounds of the present invention or a
pharmaceutically acceptable salt thereof.
[0010] It is another object of the present invention to provide a
method for treating thromboembolic disorders comprising
administering to a host in need of such treatment a therapeutically
effective amount of at least one of the compounds of the present
invention or a pharmaceutically acceptable salt thereof.
[0011] It is another object of the present invention to provide
novel compounds for use in therapy.
[0012] It is another object of the present invention to provide the
use of novel compounds for the manufacture of a medicament for the
treatment of a thromboembolic disorder.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0013] Thus, in an embodiment, the present invention provides a
novel process for making a compound of Formula I: 4
[0014] comprising:
[0015] (c) contacting a compound of Formula IVa with maleic acid to
form a compound of Formula IV; 5
[0016] (d) converting a compound of Formula IV to a compound of
Formula V; and,
[0017] (e) forming a compound of Formula I.
[0018] In a preferred embodiment, in (c), contacting with maleic
acid is performed in the presence of a first solvent, ethyl
acetate.
[0019] In another preferred embodiment, in (c), a second solvent,
1-chlorobutane, is added to enhance precipitation.
[0020] In another preferred embodiment, (d) is performed by
contacting a compound of Formula IV with HONHCOCH.sub.3 in the
presence of a base and a solvent.
[0021] In another preferred embodiment, the base is selected from
K.sub.2CO.sub.3, Na.sub.2CO.sub.3, KHCO.sub.3, NaHCO.sub.3, KF,
NaOH, and KOH.
[0022] In another preferred embodiment, the base is
K.sub.2CO.sub.3.
[0023] In another preferred embodiment, in (d), the solvent is
selected from DMSO, DMAC, N-methylpyrrolidinone, and DMF.
[0024] In another preferred embodiment, in (d), the solvent is DMF,
comprising: 0.5 to 50% by volume of water.
[0025] In another preferred embodiment, in (d), the solvent is DMF,
comprising: 10, 11, 12, 13, 14, to 15% by volume of water.
[0026] In another preferred embodiment, in (d), the solvent is DMF,
comprising: 15% by volume of water.
[0027] In another preferred embodiment, (e) is performed by
contacting a compound of Formula V with HCl in a solvent selected
from methanol, acetonitrile, isopropyl alcohol, ethanol, propanol,
acetone, methyl isobutyl ketone (MIBK), 2-butanone, and water.
[0028] In another preferred embodiment, (e) is performed by
contacting a compound of Formula V with HCl in ethanol.
[0029] In another preferred embodiment, the compound of Formula I
is a mono-HCl salt.
[0030] In another preferred embodiment, the compound of Formula I
is crystalline.
[0031] In another preferred embodiment, the compound of Formula I
is a solvate selected from ethanol, propanol, isopropanol, acetone,
MIBK, 2-butanone, and water.
[0032] In a more preferred embodiment, the compound of Formula I is
an ethanol solvate.
[0033] In another embodiment, the present invention provides a
novel process for making a compound of Formula IVa: 6
[0034] comprising:
[0035] (b) coupling compounds of Formulas II and III to form a
compound of Formula IVa.
[0036] In another preferred embodiment, the compound of Formula IVa
is used without purification in (c).
[0037] In another preferred embodiment, (b) is performed by
contacting a compound of Formula II with an acid activator, in a
solvent and a first base, followed by contacting the resulting
solution with a compound of Formula III.
[0038] In another preferred embodiment, (b) is performed by
contacting a compound of Formula II with oxalyl chloride in
acetonitrile and pyridine, followed by contacting the resulting
solution with a compound of Formula III.
[0039] In another preferred embodiment, after a compound of Formula
II has been contacted with a compound of Formula III, a second base
is added to the reaction solution.
[0040] In another preferred embodiment, the second base is
diisopropylethylamine.
[0041] In another embodiment, the present invention provides a
novel process for making a compound of Formula II: 7
[0042] comprising:
[0043] (a) contacting a compound of Formula VI with a compound of
Formula VII to form a compound of Formula VIII; and,
[0044] (a.sub.1) converting a compound of Formula VIII to a
compound of Formula II.
[0045] In another embodiment, the present invention provides a
novel compound of Formula I: 8
[0046] wherein I is a mono-HCl salt.
[0047] In another preferred embodiment, the compound of Formula I
is crystalline.
[0048] In another preferred embodiment, the compound of Formula I
is an ethanol solvate.
[0049] In another embodiment, the present invention provides a
novel compound of Formula IV: 9
[0050] In another embodiment, the present invention provides a
novel compound of Formula Va: 10
[0051] or a pharmaceutically acceptable salt form thereof.
[0052] In another embodiment, the present invention provides novel
pharmaceutical compositions, comprising: a pharmaceutically
acceptable carrier and a therapeutically effective amount of a
compound of the present invention or a pharmaceutically acceptable
salt form thereof.
[0053] In another embodiment, the present invention provides a
novel method for treating a thromboembolic disorder, comprising:
administering to a patient in need thereof a therapeutically
effective amount of a compound of the present invention or a
pharmaceutically acceptable salt form thereof.
[0054] In another embodiment, the present invention provides a
compound of the present invention for use in therapy.
[0055] In another embodiment, the present invention provides the
use of a compound of the present invention for the manufacture of a
medicament for the treatment of a thromboembolic disorder.
Definitions
[0056] As used herein, the following terms and expressions have the
indicated meanings. It will be appreciated that the compounds of
the present invention may contain an asymmetrically substituted
carbon atom, and may be isolated in optically active or racemic
forms. It is well known in the art how to prepare optically active
forms, such as by resolution of racemic forms or by synthesis from
optically active starting materials. All chiral, diastereomeric,
and racemic forms and all geometric isomeric forms of a structure
are intended, unless the specific stereochemistry or isomer form is
specifically indicated.
[0057] The processes of the present invention are contemplated to
be practiced on at least a multigram scale, kilogram scale,
multikilogram scale, or industrial scale. Multigram scale, as used
herein, is preferably the scale wherein at least one starting
material is present in 10 grams or more, more preferably at least
50 grams or more, even more preferably at least 100 grams or more.
Multikilogram scale, as used herein, is intended to mean the scale
wherein more than one kilogram of at least one starting material is
used. Industrial scale as used herein is intended to mean a scale
which is other than a laboratory scale and which is sufficient to
supply product sufficient for either clinical tests or distribution
to consumers.
[0058] The term "substituted," as used herein, means that any one
or more hydrogens on the designated atom are replaced with a
selection from the indicated group, provided that the designated
atom's normal valency is not exceeded, and that the substitution
results in a stable compound. When a substituent is keto (i.e.,
.dbd.O), then 2 hydrogens on the atom are replaced. Keto
substituents are not present on aromatic moieties. When a ring
system (e.g., carbocyclic or heterocyclic) is said to be
substituted with a carbonyl group or a double bond, it is intended
that the carbonyl group or double bond be part (i.e., within) of
the ring.
[0059] The present invention is intended to include all isotopes of
atoms occurring in the present compounds. Isotopes include those
atoms having the same atomic number but different mass numbers. By
way of general example and without limitation, isotopes of hydrogen
include tritium and deuterium. Isotopes of carbon include C-13 and
C-14.
[0060] The reactions of the synthetic methods claimed herein may be
preferably carried out in the presence of a base, the base being
any of a variety of bases, the presence of which in the reaction
facilitates the synthesis of the desired product. Suitable bases
may be selected by one of skill in the art of organic synthesis.
Suitable bases include, but are not limited to, inorganic bases
including, but not limited to, alkali metal, alkali earth metal,
thallium, and ammonium hydroxides, alkoxides, phosphates, and
carbonates, including, but not limited to, sodium hydroxide,
potassium hydroxide, sodium carbonate, potassium carbonate, cesium
carbonate, thallium hydroxide, thallium carbonate,
tetra-n-butylammonium carbonate, and ammonium hydroxide.
[0061] The reactions of the synthetic methods claimed herein may be
carried out in solvents that may be readily selected by one of
skill in the art of organic synthesis, the solvents generally are
any one that is substantially non-reactive with the starting
materials (reactants), intermediates, or products at the
temperatures at which the reactions are carried out, i.e.,
temperatures which may range from the solvent's freezing
temperature to the solvent's boiling temperature. A given reaction
may be carried out in one solvent or a mixture of more than one
solvent. Depending on the particular reaction step, suitable
solvents for a particular reaction step may be selected.
[0062] Suitable ether solvents include: dimethoxymethane,
tetrahydrofuran, 1,3-dioxane, 1,4-dioxane, furan, diethyl ether,
ethylene glycol dimethyl ether, ethylene glycol diethyl ether,
diethylene glycol dimethyl ether, diethylene glycol diethyl ether,
triethylene glycol dimethyl ether, or t-butyl methyl ether.
[0063] Suitable aprotic solvents may include, by way of example and
without limitation, tetrahydrofuran (THF), dimethylformamide (DMF),
dimethylacetamide (DMAC),
1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidin- one (DMPU),
1,3-dimethyl-2-imidazolidinone (DMI), N-methylpyrrolidinone (NMP),
formamide, N-methylacetamide, N-methylformamide, acetonitrile,
dimethyl sulfoxide, propionitrile, ethyl formate, methyl acetate,
hexachloroacetone, acetone, ethyl methyl ketone, ethyl acetate,
sulfolane, N,N-dimethylpropionamide, tetramethylurea, nitromethane,
nitrobenzene, or hexamethylphosphoramide.
[0064] The phrase "pharmaceutically acceptable" is employed herein
to refer to those compounds, materials, compositions, and/or dosage
forms which are, within the scope of sound medical judgment,
suitable for use in contact with the tissues of human beings and
animals without excessive toxicity, irritation, allergic response,
or other problem or complication, commensurate with a reasonable
benefit/risk ratio.
[0065] As used herein, "pharmaceutically acceptable salts" refer to
derivatives of the disclosed compounds wherein the parent compound
is modified by making acid or base salts thereof. Examples of
pharmaceutically acceptable salts include, but are not limited to,
mineral or organic acid salts of basic groups including, but not
limited to, amines, and alkali or organic salts of acidic groups
including, but not limited to, carboxylic acids. The
pharmaceutically acceptable salts include conventional non-toxic
salts or quaternary ammonium salts of the parent compound formed,
for example, from non-toxic inorganic or organic acids. For
example, conventional non-toxic salts include those derived from
inorganic acids including, but not limited to, hydrochloric,
hydrobromic, sulfuric, sulfamic, phosphoric, and nitric; and the
salts prepared from organic acids including, but not limited to,
acetic, propionic, succinic, glycolic, stearic, lactic, malic,
tartaric, citric, ascorbic, pamoic, maleic, hydroxymaleic,
phenylacetic, glutamic, benzoic, salicylic, sulfanilic,
2-acetoxybenzoic, fumaric, toluenesulfonic, methanesulfonic, ethane
disulfonic, oxalic, and isethionic.
[0066] The pharmaceutically acceptable salts of the present
invention can be synthesized from the parent compound that contains
a basic or acidic moiety by conventional chemical methods.
Generally, salts can be prepared by reacting the free acid or base
forms of these compounds with a stoichiometric amount of the
appropriate base or acid in water or in an organic solvent, or in a
mixture of the two; generally, nonaqueous media like ether, ethyl
acetate, ethanol, isopropanol, or acetonitrile is preferred. Lists
of suitable salts are found in Remington's Pharmaceutical Sciences,
17th ed., Mack Publishing Company, Easton, Pa., 1985, p. 1418, the
disclosure of which is hereby incorporated by reference.
[0067] As used herein, "treating" or "treatment" cover the
treatment of a disease-state in a mammal, particularly in a human,
and include: (a) preventing the disease-state from occurring in a
mammal, in particular, when such mammal is predisposed to the
disease-state but has not yet been diagnosed as having it; (b)
inhibiting the disease-state, i.e., arresting it development;
and/or (c) relieving the disease-state, i.e., causing regression of
the disease state.
Synthesis
[0068] The processes of the present invention can be practiced in a
number of ways depending on the solvent, base, and temperature
chosen. As one of ordinary skill in the art of organic synthesis
recognizes, the time for reaction to run to completion as well as
yield will be dependent upon all of the variables selected. The
following schemes show a representation of the overall sequence of
the present invention.
[0069] Preparation of Formula VIII: 11
[0070] VI can be converted to VIII by a novel hydrazine in-situ
trapping procedure. The hydrazine intermediate can be prepared by
treating VI with HCl and NaNO.sub.2. Preferably, VI is added to a
cooled (e.g., -10 to -5.degree. C.) solution of HCl. The NaNO.sub.2
can then added and the solution preferably maintained at a
temperature of from 0-10.degree. C. At this point, AcOH can be
added to the solution. SnCl.sub.2.2H.sub.2O can then be added to
complete formation of the hydrazine. The resulting product may be
isolated or used in situ. Preferably, it is used in situ.
[0071] VIII can then be formed by addition of VII to the newly
formed hydrazine. This addition is preferably performed in the
presence of MeOH and at a temperature of from 35-55.degree. C.
[0072] Preparation of Formula II: 12
[0073] Oxidation of VIII should provide II. The oxidation is
performed by contacting VIII with an oxidant in the presence of a
solvent and optionally a buffer.
[0074] One of ordinary skill in the art would recognize that
oxidants such as KMnO.sub.4 or NaClO.sub.2 can be used. Preferably,
KMnO.sub.4, in the presence of a buffer, is used as the oxidant.
VIII can be suspended in an alcoholic solvent (e.g., t-butyl
alcohol). The suspension is preferably maintained at a temperature
of from 35-50.degree. C. An aqueous solution of a buffer known to
those of skill in the art (e.g., monobasic sodium phosphate
monohydrate) can then be added. Preferably, the buffer is about 0.5
to 4N. Aqueous KMnO.sub.4 can then be added to the reaction
solution. After the reaction is complete, II can be isolated.
[0075] Preparation of Formula IVa: 13
[0076] IVa can be formed by coupling II and III. The coupling is
preferably performed by contacting II with an acid activator, in a
solvent and in the presence of a base, followed by contacting the
resulting solution with III. An acid activator like thionyl
chloride or oxalyl chloride can be used, with oxalyl chloride being
a preferred activator. The addition of the acid activator is
preferably performed at a temperature of from 10-30.degree. C.
[0077] Contacting II and oxalyl chloride can be performed in a
solvent selected from acetonitrile, THF, and methylene chloride,
with acetonitrile being preferred. The first base can be selected
from DMAP, triethylamine, diisopropylethylamine, N-methyl
morpholine, and pyridine, with pyridine being preferred. The amount
of first base present is preferably from 0.2 to 1 molar equivalent
based on II, more preferably it is 0.4 molar equivalents.
[0078] The desired amount of oxalyl chloride to be added will be
based on the amount of II present in the solution and the amount of
water present in the solution. The amount of water present can be
determined by known means, such as the Karl Fischer titration.
Preferably, the number of moles of oxalyl chloride added is equal
to or slightly greater than the sum of the number of moles of II
and water present.
[0079] Once II has been activated, it can be contacted with III.
Preferably, the reaction mixture is cooled to from 0-10.degree. C.
prior to contacting with III. After contacting III with the
reaction mixture, a second base is preferably added. The second
base can be selected from diisopropylethylamine, pyridine, DMAP,
triethylamine, and N-methyl morpholine, with diisopropylethylamine
being preferrred. The amount of second base present is preferably
from about 1-3 molar equivalents, more preferably about 2.2 molar
equivalents based on the amount of II present.
[0080] Preparation of Formula IV: 14
[0081] IV can be formed from IVa with or without purification of
IVa. Preferably, IV is formed from IVa without purification. IVa is
usually isolated as an oily substance. IVa is preferably taken up
in a first solvent and maleic acid is added. To this solution can
be added a second solvent to enhance or accelerate precipitation of
IV. Preferably from 0.9 to 1.1 molar equivalents of maleic acid are
present based on the amount of II present, more preferably about
0.95 molar equivalents. The first solvent can be selected from the
group acetone, chloroform, ethyl acetate MIBK, i-propyl acetate,
i-propyl alcohol, and THF, and is preferably ethyl acetate. The
second solvent can be selected from the group 1-chlorobutane,
heptane, hexane, methylene chloride, and TBME, and is preferably
1-chlorobutane. Preferably, this reaction is run at about room
temperature.
[0082] Preparation of Formula V: 15
[0083] V can be prepared by contacting IV with HONHCOCH.sub.3 in
the presence of a base and a solvent. Preferably, the base is
selected from K.sub.2CO.sub.3, Na.sub.2CO.sub.3, KHCO.sub.3,
NaHCO.sub.3, KF, NaOH, and KOH, with K.sub.2CO.sub.3 being a more
preferred base. The solvent may be selected from DMSO,
dimethylformamide (DMF), dimethylacetamide (DMAC),
1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU),
1,3-dimethyl-2-imidazolidinone (DMI), and N-methylpyrrolidinone
(NMP). A preferred solvent is DMF. It is preferred that the DMF
comprises 0.5 to 50% by volume of water, more preferably, 0.5, 1,
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, to 15% by volume of
water, even more preferably 10, 11, 12, 13, 14, to 15% by volume of
water, and still more preferably 15% by volume of water.
[0084] Preferably, HONHCOCH.sub.3, DMF, and K.sub.2CO.sub.3 are
mixed together followed by contacting with water. This reaction
mixture is preferably kept at about 20-30.degree. C. Upon
contacting of the reaction mixture with IV, the reaction is
preferably stirred at about room temperature.
[0085] Preparation of Formula I: 16
[0086] I can be formed from V by dissolving V in a solvent and
contacting this solution with HCl. Preferably, the solvent is
selected from methanol, acetonitrile, isopropyl alcohol, ethanol,
propanol, acetone, methyl isobutyl ketone (MIBK), 2-butanone, and
water, with ethanol being a more preferred solvent. V is preferably
taken up in a solvent (e.g., ethanol) at a temperature of from
60-80.degree. C. HCl is preferably contacted with the solution that
is at a temperature of from 20-40.degree. C. Preferably, the HCl is
in an alcoholic solution. The alcoholic solution is preferably
i-propyl alcohol.
[0087] I preferably precipitates from the reaction mixture. This
precipitation can be enhanced by cooling the mixture to a
temperature of about 0-10.degree. C. Preferably I is a crystalline
mono-HCl salt. More preferably, I is a solvate selected from
ethanol, propanol, isopropanol, acetone, MIBK, 2-butanone, and
water. Even more preferably, I is an ethanol solvate.
[0088] Other features of the invention will become apparent in the
course of the following descriptions of exemplary embodiments that
are given for illustration of the invention and are not intended to
be limiting thereof.
EXAMPLES
Example 1
Preparation of VIII
[0089] To a 40 L Hastelloy "C" reactor fitted with an overhead air
stirrer, thermocouple, condenser and nitrogen inlet, was charged
conc. HCl (5.5 L). The reactor was cooled to between -5 and
-10.degree. C. VI (tan solid, 726 g, 5.3 mol) was added over 12
minutes while maintaining the internal temperature between -5 and
-7.degree. C. An additional 500 mL of conc. HCl was used to rinse
down any VI hung up on the walls of the reactor. The resulting tan
slurry was maintained at -5.degree. C. over the next 10 minutes
while a solution of sodium nitrite (450 g, 6.5 mol) in 3.1 L of
purified water was prepared. The first 1500 mL of the sodium
nitrite solution was added over 20 minutes wherein the internal
temperature rose to 10.degree. C. The addition was stopped for 30
minutes in order for the internal temperature to cool down and
equilibrate to 2-3.degree. C. The addition of sodium nitrite
solution was resumed and the remaining 1.7 L was added over 30
minutes, while maintaining a temperature of 5-7.degree. C. The
batch was agitated for an additional 30 minutes at 6.degree. C.
Acetic acid (1.8 L) was added in one bolus with no appreciable
change in the internal temperature (6.degree. C.). A solution of
SnCl.sub.2.2H.sub.2O (2.8 kg, 12.2 mol) was prepared in 1.9 L
H.sub.2O and 1.9 L of conc. HCl and added to the reaction over 55
minutes while maintaining the temperature between 6-10.degree. C.
The resulting white "milkshake-like" slurry was agitated for an
additional 30 minutes.
[0090] Methanol (10 L) was charged as one bolus into the reactor
and the reaction mixture was heated to 40.degree. C. A solution of
4,4,4-trifluoro-2-furyl-1,3-butanedione (VII, 830 mL, 1.2 kg, 5.6
mol) in 3.1 L of MeOH was added over 35 minutes while maintaining
an internal temperature between 41-43.degree. C. After addition was
complete, the batch was held between 45-50.degree. C. for an
additional 1.5 h whereupon the heat was shut off and the resulting
orange slurry was allowed to cool to ambient temperature overnight
(16 h) under a nitrogen atmosphere. The next morning, the batch was
cooled further to help promote precipitation of VIII. The batch was
cooled down to 0.degree. C. and held for 1 hour at 0.degree. C.
before dropping the slurry onto a Dacron filter cloth in a 32 cm
Buchner funnel. The filtration took 1 hour and the cake depth was
determined to be 3.5 cm. The cake was rinsed with 3 L of cold
(0-5.degree. C.) 50/50 isopropanol/water followed by 2.9 L of
water. The wet cake (3.4 kg) was dried to constant weight in a
vacuum oven at 45.degree. C. and 22 mm Hg over the weekend to
produce 1.3 Kg of VIII as a yellow solid (1.3 Kg, 94.5 wt %, 71.7%
corrected yield).
Example 2
Preparation of II
[0091] A 50 L Hastelloy C reactor, equipped with an overhead air
stirrer, a thermocouple, an addition funnel, a condenser, and a
nitrogen inlet was charged with melted t-butyl alcohol (10 L),
followed by solid VIII (1160 g). An additional quantity of t-butyl
alcohol (4.5 L) was used for purposes of rinsing the original
containers and was added to the reactor. The suspension was warmed
to between 38.degree. C. and 45.degree. C. until a homogeneous
solution resulted. An aqueous solution of monobasic sodium
phosphate monohydrate (1245 g in 5.2 L of purified water) was added
to the mixture over approx. 15 min between 35.degree. C. and
45.degree.C. Celite.RTM. 545 (3.2 Kg) was added to the reactor
between 38.degree. C. and 45.degree. C. and stirring was maintained
to insure even dispersion of the solid. A commercial 40% aqueous
solution of sodium permanganate (5.76 L) was added slowly over
approx. 2.5 h, maintaining an internal temperature range between
42.degree. C. and 50.degree. C. The reaction mass was allowed to
cool to ambient temperature and was held overnight with continuous
stirring.
[0092] The next morning, the mixture was again heated to between
45.degree. C. and 50.degree. C. and t-butyl methyl ether (6.0 L)
was added, followed by solid Celite.RTM. 545 (3.2 Kg) and neutral
alumina (4.15 Kg). The mixture was stirred for approx. 15 min,
filtered, and the cake was rinsed with t-butyl methyl ether (6 L
total rinse volume). All filtrates obtained were recombined and the
solvents were removed by distillation. When the distillation had
ceased, purified water (5 L) was added, followed by a second
distillation. The clear, homogeneous residue was diluted with water
to give 18 L of total solution. n-Chlorobutane (8 L) was added, the
biphasic mixture was slowly stirred for 15 min, and the upper layer
was separated and discarded. The weakly basic aqueous layer was
cooled to between 3.degree. C. and 7.degree. C. and 30% aqueous
citric acid solution (3.3 L) was added, whereupon the crude II
precipitated. The solids were collected by filtration and the cake
was rinsed with purified water (5.0 L total rinse volume). Wet,
yellow II was packed out and dried to constant weight in a vacuum
oven at 70.degree. C., affording dry II (815.1 g; 98.8 wt-%, 75%
yield).
Example 3
Preparation of III
[0093] III can be prepared in accordance with the procedure
described in co-pending U.S. Provisional Patent Application
60/220,932, filed Jul. 26, 2000, the contents of which are hereby
incorporated by reference. The following is an example of the
preparation of III.
[0094] Dimethylamine in THF (7.2 L of 2.0 M solution, 14.3 mol) was
charged into a 5 gallon Parr hydrogenator. 2-Formyl-imidazolyl
(1.25 kg, 13.0 mol) and methanol (2.4 L) was charged next. After
pressure testing the system with nitrogen, Pd/C (10%) (125 g,
containing approximately 50% by weight water) was charged. Jacket
cooling was set at 25.degree. C. The batch was then pressurized
with hydrogen and the pressure was maintained in the range 50-60
psig. The first 20 minutes of reaction saw a rise in the internal
temperature to 35.degree. C. and hydrogen uptake was extremely
rapid. For the next 2 hours before the hydrogen pressure was
released, the internal temperature was 30-31.degree. C. HPLC
analysis indicated that the conversion to
2-(N,N-dimethylaminomethyl)imidazole was complete (remaining
2-formyl-imidazolyl A %<2% versus
2-(N,N-dimethylaminomethyl)imidazole >98%). The batch was
filtered through a 0.5 micron cartridge filter and then through a
0.45 micron minifilter to remove Pd/C. A solution of 1/1 v/v
MeOH/THF (5 L) was used to wash out the reactor and line and was
directed via the cartridge filters to the carboy containing the
rest of the filtrate. The combined filtrates were concentrated via
rotary evaporator to a 2.3 kg solution (contained 1.6 Kg of
2-(N,N-dimethylaminomethyl)imidazole), which was then used directly
for next step.
[0095] To each of two 22 L five neck round bottom flasks equipped
with over head air stirrer, thermocouple, and distillation set-up
with nitrogen cap was charged a solution of crude
2-(N,N-dimethylaminomethyl)i- midazole (4.86 kg of a solution made
by the above procedure that contained 3.0 Kg of
2-(N,N-dimethylaminomethyl)imidazole). To each of the two reactors,
anhydrous DMSO (10.0 L) was then introduced to give a dark amber
clear solution. The residual MeOH and THF from the crude
2-(N,N-dimethylaminomethyl)imidazole in each of the two reactors
was subsequently distilled off in vacuo at 50-60.degree. C. before
1-amino-2-fluoro-4-iodobenzene (2.15 Kg, 9.05 mole) and powdered
K.sub.2CO.sub.3 (2.5 Kg, 18.1 mole, 2.0 equiv) were added to each
of the two reactors at 40-50.degree. C., respectively. Each of the
two reactors was then degassed three times with a vacuum/nitrogen
cycle ending on nitrogen before being charged with powdered CuI
(260 g, 1.35 mole, 0.15 equiv). The resulting reaction mixture in
each of the two reactors was degassed three times again with a
vacuum/nitrogen cycle ending on nitrogen before being warmed to
125-130.degree. C.
[0096] When the reaction was deemed complete after 16 h at
125-130.degree. C. (1-amino-2-fluoro-4-iodobenzene<5% at 254 nm
via HPLC analysis), the reaction mixture in each of the two
reactors was cooled to 40-50.degree. C. To each of the two reactors
was added 4.0 L of saturated NH.sub.4Cl aqueous solution, and the
resulting mixture was agitated for 1 h at 20-25.degree. C. The
mixture was then filtered through a Celite.RTM. bed, and each of
the two reactors was washed with 1.0 L of saturated NH.sub.4Cl
aqueous solution and 8.5 L of ethyl acetate. Half of the combined
filtrates and washing solution were sequentially poured into a 40 L
reactor, and the mixture was agitated at 20-25.degree. C. for 0.5 h
before the two layers were separated. The combined aqueous layers
were poured back into the 40 L reactor and were extracted with
ethyl acetate (4.times.15 L). During the process of the organic
solvent extraction, emulsion colloid was resolved by filtration of
the mixture through a Celite.RTM. bed before the two layers were
separated. The combined organic extracts were then washed with 6.0
L of saturated NH.sub.4Cl aqueous solution, dried over MgSO.sub.4
(2.0 Kg), and decolorized over active carbon (charcoal, 500 g) at
20-25.degree. C. for 1 h in two separate 22 L reactors. The mixture
was filtered through a Celite.RTM. bed, and each of the reactors
was washed with ethyl acetate (2 L). The combined organic filtrates
were then poured into a 40 L reactor, and a total of 68 L of ethyl
acetate were successively distilled off in vacuo at 45-50.degree.
C. The residual slurry of the crude III in 9.0 L of ethyl acetate
was subsequently transferred into a 22 L reactor, and the mixture
was warmed to reflux (77-78.degree. C.) to give a brown to black
solution. Heptanes (6.0 L) were then added to the solution at
70.degree. C., and the solution was cooled to 45-50.degree. C.
before being treated with active carbon (charcoal, 400 g). The
mixture was warmed to reflux again for 1 h before being filtered
through a Celite.RTM. bed at 50-55.degree. C. The Celite.RTM. bed
was washed with 2.0 L of ethyl acetate, and the combined filtrates
and washing solution were poured back into a clean 22 L reactor. A
total of 5.0 L of ethyl acetate was distilled off in vacuo at
45-50.degree. C., and an additional 5.0 L of heptanes were added
into the reactor at 50.degree. C. The mixture was then gradually
cooled to 20-25.degree. C. and stirred at 20-25.degree. C. for 1 h
before being cooled to 5-10.degree. C. for 2 h to precipitate III.
The solids were collected by filtration on a 27 cm porcelain funnel
lined with Dacron.RTM. cloth and washed with 20% (v/v) of
TBME/heptanes (2.times.2.5 L). The solids were dried in vacuo with
nitrogen purge at 40-45.degree. C. to a constant weight. The first
crop of III (1.749 Kg, 4.235 Kg theoretical, 41.3%) was obtained as
pale-yellow crystals.
[0097] The combined mother liquor and washing solution was then
concentrated in vacuo to afford the second crop of III (500 g,
4.235 kg theoretical, 11.8%; a total of 53.1% yield) as pale-yellow
crystals.
Example 4
Preparation of IVa and IV
[0098] II (781 g, 2.61 mol) was combined with acetonitrile (11.3
L). The amount of water present in the solution was determined by
performing a Karl Fischer titration. The volume of oxalyl chloride
to be charged was calculated by adding the moles of II plus moles
of water determined to be present to give moles of oxalyl chloride.
Pyridine (81 mL, 1.0 mol) was charged followed by oxalyl chloride
(227 mL, 2.60 mol). The reaction was warmed to 55-60.degree. C. and
held at that temperature for 1 hour. The progress of the reaction
was followed by drawing a sample and quenching into NH.sub.4OH.
Once the reaction was considered complete, a vacuum distillation
was performed to remove 12% (v/v) of the solvent. Following the
distillation fresh acetonitrile was added back to the reaction to
replace the volume removed by the distillation.
[0099] The reaction mixture was chilled to 5.degree. C. followed by
the addition of III (598 g, 2.55 mol). An exotherm of 12.degree. C.
accompanied the addition. After allowing the solution to return to
5.degree. C., diisopropylethylamine (975 mL, 5.60 mol) was added to
the reaction over 60 minutes via addition funnel. Following the
addition, the cooling bath was removed and the reaction was allowed
to return to room temperature. Two hours following the addition of
base the reaction was complete. The reaction was diluted with EtOAc
(12 L) and washed with water (2.times.8 L). The aqueous washes were
combined and back extracted with EtOAc (1.times.8 L). The organic
fractions were combined and dried over MgSO.sub.4, filtered and
concentrated to yield a brown oil, IVa.
[0100] The oil was reconstituted with EtOAc (11.3 L) and
transferred to a 40 L kettle. Maleic acid (290 g, 2.50 mol) was
added to the EtOAc solution that was then stirred at room
temperature for 60 minutes. Approximately 15 minutes after the
addition of maleic acid the resulting salt, IV, began to
precipitate out of solution. 1-Chlorobutane (24 L) was added over
60-90 minutes to ensure complete precipitation. Following the
addition of 1-chlorobutane, the IV solution was stirred at room
temperature for 3 h. The salt was isolated by filtration and washed
with 1-chlorobutane (6 L). The solids were dried in a 75.degree. C.
vacuum oven to constant weight to give 1.49 Kg (100.7 wt. %, 94.1%
yield) of IV.
Example 5
Preparation of V
[0101] A 22 L reaction flask was charged with DMF (8 L), potassium
carbonate (1576 g, 11.4 mol), and acetohydroxamic acid (428 g, 5.7
mol) and stirred at rt. Water (1.2 L, note: For Batch 1, 0.8 L of
water was first added and an additional 0.4 L of water was added
after stirring at rt for 27 h) was added slowly while keeping the
reaction temperature at 20-30.degree. C. After the reaction mixture
was stirred for 30 min at 20-30.degree. C., IV (1200 g, 1.9 mol)
was added. The reaction mixture was stirred at rt for 4 to 20 h.
This reaction mixture was quenched into 12 L of water in a 40 L
reactor with vigorous agitation. The resulting slurry was stirred
at rt for 2 h and then at 2-10.degree. C. for another 1 h. The
solid was filtered with a Dacron filter cloth. The cake was washed
with cold water (8 L) and followed by cold acetonitrile (2 L) and
dried in a vacuum oven to constant weight to give a crude product
(1012 g). The crude product was dissolved in 12.5 L of acetonitrile
at 65-80.degree. C. After the solution was cooled to 25-37.degree.
C., water (2 L) was added over 2 h period while allowing the pot to
cool to rt. The formed slurry was stirred at rt for 1 h. After
cooling to 2-10.degree. C., the solid was filtered with a Dacron
filter cloth. The cake was washed with cold acetonitrile (4-6 L)
and dried in a vacuum oven to constant weight to give the product V
(92.3 g, 89%). HRMS for C.sub.24H.sub.21F.sub.4O.sub.2N.sub.8
(M+H).sup.+ calcd 529.1724, found 529.1722. .sup.1H-NMR (300 MHz,
DMSO-d.sub.6) 2.09 (6H), 3.29 (2H), 6.54 (2H), 6.96 (1H), 7.41-7.75
(7H), 8.06 (1H), 10.65 (1H). .sup.19F-NMR -119.632 (1F), -61.257
(3F).
Example 6
Preparation of I
[0102] A 22 L reaction flask with overhead stirring, water
condenser, and temperature probe was charged with ethanol (10 L)
and V (monohydrate form, 850 g, 1.56 mol). The reaction mixture was
heated to 65 to 80.degree. C. to give a clear solution. After
cooling to about 55.degree. C., the warm solution was filtered
through a cartridge filter. After transferring the filtrate back to
the clean 22 L reactor and cooling the solution to 20-37.degree.
C., 4.6N HCl in IPA solution (355 mL, 1.63 mol) was charged through
an addition funnel. After a slurry was formed, the mixture was
stirred at rt for 1 h, and then at 2-8.degree. C. for another 1 h.
The solid was collected in a Buchner funnel with Dacron filter
cloth. The cake was washed with cold ethanol (2 L) and followed by
tert-butyl methyl ether (6 L), dried in a vacuum oven at 50.degree.
C. to give the product I (858 g, 98%). M.p. 258 C (dec).
.sup.1H-NMR (300 MHz, DMSO-d.sub.6) 1.02 (ethanol), 2.74 (6H), 3.40
(ethanol), 4.35 (2H), 6.59(2H), 7.18 (1H), 7.34-7.80 (7H), 8.09
(1H), 10.99 (1H). .sup.19F-NMR -118.174 (1F), -61.229 (3F).
Example 7
Preparation of Va
[0103] To a solution of V (5.06 g) in chloroform (40 mL) and
methanol (120 mL) was added 35% H.sub.2O.sub.2 (20 mL) at rt. The
reaction mixture was stirred at rt over 66 h. Water (180 mL) was
then added to the reaction mixture and the resulting slurry was
stirred at rt for 30 min. The solid was collected by filtration and
dried in vacuo with nitrogen purge at rt to a constant weight (3.97
g).
UTILITY
[0104] The novel compounds of the present invention are useful as
anticoagulants for the treatment or prevention of thromboembolic
disorders in mammals. The term "thromboembolic disorders" as used
herein includes arterial or venous cardiovascular or
cerebrovascular thromboembolic disorders, including, for example,
unstable angina, first or recurrent myocardial infarction, ischemic
sudden death, transient ischemic attack, stroke, atherosclerosis,
venous thrombosis, deep vein thrombosis, thrombophlebitis, arterial
embolism, coronary and cerebral arterial thrombosis, cerebral
embolism, kidney embolisms, and pulmonary embolisms. The
anticoagulant effect of compounds of the present invention is
believed to be due to inhibition of factor Xa or thrombin.
[0105] The effectiveness of compounds of the present invention as
inhibitors of factor Xa was determined using purified human factor
Xa and synthetic substrate. The rate of factor Xa hydrolysis of
chromogenic substrate S2222 (Kabi Pharmacia, Franklin, Ohio) was
measured both in the absence and presence of compounds of the
present invention. Hydrolysis of the substrate resulted in the
release of pNA, which was monitored spectrophotometrically by
measuring the increase in absorbance at 405 nM. A decrease in the
rate of absorbance change at 405 nm in the presence of inhibitor is
indicative of enzyme inhibition. The results of this assay are
expressed as inhibitory constant, K.sub.i.
[0106] Factor Xa determinations were made in 0.10 M sodium
phosphate buffer, pH 7.5, containing 0.20 M NaCl, and 0.5% PEG
8000. The Michaelis constant, K.sub.m, for substrate hydrolysis was
determined at 25.degree. C. using the method of Lineweaver and
Burk. Values of K.sub.i were determined by allowing 0.2-0.5 nM
human factor Xa (Enzyme Research Laboratories, South Bend, Ind.) to
react with the substrate (0.20 mM-1 mM) in the presence of
inhibitor. Reactions were allowed to go for 30 minutes and the
velocities (rate of absorbance change vs time) were measured in the
time frame of 25-30 minutes. The following relationship was used to
calculate K.sub.i values:
(v.sub.o-v.sub.s)/v.sub.s=I/(K.sub.i(1+S/K.sub.m))
[0107] where:
[0108] v.sub.o is the velocity of the control in the absence of
inhibitor;
[0109] v.sub.s is the velocity in the presence of inhibitor;
[0110] I is the concentration of inhibitor;
[0111] K.sub.i is the dissociation constant of the enzyme:inhibitor
complex;
[0112] S is the concentration of substrate;
[0113] K.sub.m is the Michaelis constant.
[0114] Compounds tested in the above assay are considered to be
active if they exhibit a K.sub.i of .ltoreq.10 .mu.M. Preferred
compounds of the present invention have K.sub.i's of .ltoreq.1
.mu.M. More preferred compounds of the present invention have
K.sub.i's of .ltoreq.0.1 .mu.M. Even more preferred compounds of
the present invention have K.sub.i's of .ltoreq.0.01 .mu.M. Still
more preferred compounds of the present invention have K.sub.i's of
.ltoreq.0.001 .mu.M. Using the methodology described above, a
number of compounds of the present invention were found to exhibit
a K.sub.i of <10 .mu.M, thereby confirming the utility of the
compounds of the present invention as effective Xa inhibitors.
[0115] The antithrombotic effect of compounds of the present
invention can be demonstrated in a rabbit arterio-venous (AV) shunt
thrombosis model. In this model, rabbits weighing 2-3 kg
anesthetized with a mixture of xylazine (10 mg/kg i.m.) and
ketamine (50 mg/kg i.m.) are used. A saline-filled AV shunt device
is connected between the femoral arterial and the femoral venous
cannulae. The AV shunt device consists of a piece of 6-cm tygon
tubing which contains a piece of silk thread. Blood will flow from
the femoral artery via the AV-shunt into the femoral vein. The
exposure of flowing blood to a silk thread will induce the
formation of a significant thrombus. After forty minutes, the shunt
is disconnected and the silk thread covered with thrombus is
weighed. Test agents or vehicle will be given (i.v.,
[0116] i.p., s.c., or orally) prior to the opening of the AV shunt.
The percentage inhibition of thrombus formation is determined for
each treatment group. The ID50 values (dose which produces 50%
inhibition of thrombus formation) are estimated by linear
regression.
[0117] The compounds of formula (I) may also be useful as
inhibitors of serine proteases, notably human thrombin, plasma
kallikrein and plasmin. Because of their inhibitory action, these
compounds are indicated for use in the prevention or treatment of
physiological reactions, blood coagulation and inflammation,
catalyzed by the aforesaid class of enzymes. Specifically, the
compounds have utility as drugs for the treatment of diseases
arising from elevated thrombin activity such as myocardial
infarction, and as reagents used as anticoagulants in the
processing of blood to plasma for diagnostic and other commercial
purposes.
[0118] Some compounds of the present invention were shown to be
direct acting inhibitors of the serine protease thrombin by their
ability to inhibit the cleavage of small molecule substrates by
thrombin in a purified system. In vitro inhibition constants were
determined by the method described by Kettner et al. in J. Biol.
Chem. 265, 18289-18297 (1990), herein incorporated by reference. In
these assays, thrombin-mediated hydrolysis of the chromogenic
substrate S2238 (Helena Laboratories, Beaumont, Tex.) was monitored
spectrophotometrically. Addition of an inhibitor to the assay
mixture results in decreased absorbance and is indicative of
thrombin inhibition. Human thrombin (Enzyme Research Laboratories,
Inc., South Bend, Ind.) at a concentration of 0.2 nM in 0.10 M
sodium phosphate buffer, pH 7.5, 0.20 M NaCl, and 0.5% PEG 6000,
was incubated with various substrate concentrations ranging from
0.20 to 0.02 mM. After 25 to 30 minutes of incubation, thrombin
activity was assayed by monitoring the rate of increase in
absorbance at 405 nm which arises owing to substrate hydrolysis.
Inhibition constants were derived from reciprocal plots of the
reaction velocity as a function of substrate concentration using
the standard method of Lineweaver and Burk. Using the methodology
described above, some compounds of this invention were evaluated
and found to exhibit a K.sub.i of less than 15 .mu.m, thereby
confirming the utility of the compounds of the present invention as
effective Xa inhibitors.
[0119] The compounds of the present invention can be administered
alone or in combination with one or more additional therapeutic
agents. These include other anti-coagulant or coagulation
inhibitory agents, anti-platelet or platelet inhibitory agents,
thrombin inhibitors, or thrombolytic or fibrinolytic agents.
[0120] The compounds are administered to a mammal in a
therapeutically effective amount. By "therapeutically effective
amount" it is meant an amount of a compound of Formula I that, when
administered alone or in combination with an additional therapeutic
agent to a mammal, is effective to prevent or ameliorate the
thromboembolic disease condition or the progression of the
disease.
[0121] By "administered in combination" or "combination therapy" it
is meant that the compound of Formula I and one or more additional
therapeutic agents are administered concurrently to the mammal
being treated. When administered in combination each component may
be administered at the same time or sequentially in any order at
different points in time. Thus, each component may be administered
separately but sufficiently closely in time so as to provide the
desired therapeutic effect. Other anticoagulant agents (or
coagulation inhibitory agents) that may be used in combination with
the compounds of this invention include warfarin and heparin, as
well as other factor Xa inhibitors such as those described in the
publications identified above under
BACKGROUND OF THE INVENTION
[0122] The term anti-platelet agents (or platelet inhibitory
agents), as used herein, denotes agents that inhibit platelet
function such as by inhibiting the aggregation, adhesion or
granular secretion of platelets. Such agents include, but are not
limited to, the various known non-steroidal anti-inflammatory drugs
(NSAIDS) such as aspirin, ibuprofen, naproxen, sulindac,
indomethacin, mefenamate, droxicam, diclofenac, sulfinpyrazone, and
piroxicam, including pharmaceutically acceptable salts or prodrugs
thereof. Of the NSAIDS, aspirin (acetylsalicyclic acid or ASA), and
piroxicam are preferred. Other suitable anti-platelet agents
include ticlopidine, including pharmaceutically acceptable salts or
prodrugs thereof. Ticlopidine is also a preferred compound since it
is known to be gentle on the gastrointestinal tract in use. Still
other suitable platelet inhibitory agents include IIb/IIIa
antagonists, thromboxane-A2-receptor antagonists and
thromboxane-A2-synthetase inhibitors, as well as pharmaceutically
acceptable salts or prodrugs thereof.
[0123] The term thrombin inhibitors (or anti-thrombin agents), as
used herein, denotes inhibitors of the serine protease thrombin. By
inhibiting thrombin, various thrombin-mediated processes, such as
thrombin-mediated platelet activation (that is, for example, the
aggregation of platelets, and/or the granular secretion of
plasminogen activator inhibitor-1 and/or serotonin) and/or fibrin
formation are disrupted. A number of thrombin inhibitors are known
to one of skill in the art and these inhibitors are contemplated to
be used in combination with the present compounds. Such inhibitors
include, but are not limited to, boroarginine derivatives,
boropeptides, heparins, hirudin and argatroban, including
pharmaceutically acceptable salts and prodrugs thereof.
Boroarginine derivatives and boropeptides include N-acetyl and
peptide derivatives of boronic acid, such as C-terminal
a-aminoboronic acid derivatives of lysine, ornithine, arginine,
homoarginine and corresponding isothiouronium analogs thereof. The
term hirudin, as used herein, includes suitable derivatives or
analogs of hirudin, referred to herein as hirulogs, such as
disulfatohirudin. Boropeptide thrombin inhibitors include compounds
described in Kettner et al., U.S. Pat. No. 5,187,157 and European
Patent Application Publication Number 293 881 A2, the disclosures
of which are hereby incorporated herein by reference. Other
suitable boroarginine derivatives and boropeptide thrombin
inhibitors include those disclosed in PCT Application Publication
Number 92/07869 and European Patent Application Publication Number
471,651 A2, the disclosures of which are hereby incorporated herein
by reference.
[0124] The term thrombolytics (or fibrinolytic) agents (or
thrombolytics or fibrinolytics), as used herein, denotes agents
that lyse blood clots (thrombi). Such agents include tissue
plasminogen activator, anistreplase, urokinase or streptokinase,
including pharmaceutically acceptable salts or prodrugs thereof.
The term anistreplase, as used herein, refers to anisoylated
plasminogen streptokinase activator complex, as described, for
example, in European Patent Application No. 028,489, the disclosure
of which is hereby incorporated herein by reference herein. The
term urokinase, as used herein, is intended to denote both dual and
single chain urokinase, the latter also being referred to herein as
prourokinase.
[0125] Administration of the compounds of Formula I of the
invention in combination with such additional therapeutic agent,
may afford an efficacy advantage over the compounds and agents
alone, and may do so while permitting the use of lower doses of
each. A lower dosage minimizes the potential of side effects,
thereby providing an increased margin of safety.
[0126] The compounds of the present invention are also useful as
standard or reference compounds, for example as a quality standard
or control, in tests or assays involving the inhibition of factor
Xa. Such compounds may be provided in a commercial kit, for
example, for use in pharmaceutical research involving factor Xa.
For example, a compound of the present invention could be used as a
reference in an assay to compare its known activity to a compound
with an unknown activity. This would ensure the experimenter that
the assay was being performed properly and provide a basis for
comparison, especially if the test compound was a derivative of the
reference compound. When developing new assays or protocols,
compounds according to the present invention could be used to test
their effectiveness.
[0127] The compounds of the present invention may also be used in
diagnostic assays involving factor Xa. For example, the presence of
factor Xa in an unknown sample could be determined by addition of
chromogenic substrate S2222 to a series of solutions containing
test sample and optionally one of the compounds of the present
invention. If production of pNA is observed in the solutions
containing test sample, but no compound of the present invention,
then one would conclude factor Xa was present.
Dosage and Formulation
[0128] The compounds of this invention can be administered in such
oral dosage forms as tablets, capsules (each of which includes
sustained release or timed release formulations), pills, powders,
granules, elixirs, tinctures, suspensions, syrups, and emulsions.
They may also be administered in intravenous (bolus or infusion),
intraperitoneal, subcutaneous, or intramuscular form, all using
dosage forms well known to those of ordinary skill in the
pharmaceutical arts. They can be administered alone, but generally
will be administered with a pharmaceutical carrier selected on the
basis of the chosen route of administration and standard
pharmaceutical practice.
[0129] The dosage regimen for the compounds of the present
invention will, of course, vary depending upon known factors, such
as the pharmacodynamic characteristics of the particular agent and
its mode and route of administration; the species, age, sex,
health, medical condition, and weight of the recipient; the nature
and extent of the symptoms; the kind of concurrent treatment; the
frequency of treatment; the route of administration, the renal and
hepatic function of the patient, and the effect desired. A
physician or veterinarian can determine and prescribe the effective
amount of the drug required to prevent, counter, or arrest the
progress of the thromboembolic disorder.
[0130] By way of general guidance, the daily oral dosage of each
active ingredient, when used for the indicated effects, will range
between about 0.001 to 1000 mg/kg of body weight, preferably
between about 0.01 to 100 mg/kg of body weight per day, and most
preferably between about 1.0 to 20 mg/kg/day. Intravenously, the
most preferred doses will range from about 1 to about 10
mg/kg/minute during a constant rate infusion. Compounds of this
invention may be administered in a single daily dose, or the total
daily dosage may be administered in divided doses of two, three, or
four times daily.
[0131] Compounds of this invention can be administered in
intranasal form via topical use of suitable intranasal vehicles, or
via transdermal routes, using transdermal skin patches. When
administered in the form of a transdermal delivery system, the
dosage administration will, of course, be continuous rather than
intermittent throughout the dosage regimen.
[0132] The compounds are typically administered in admixture with
suitable pharmaceutical diluents, excipients, or carriers
(collectively referred to herein as pharmaceutical carriers)
suitably selected with respect to the intended form of
administration, that is, oral tablets, capsules, elixirs, syrups
and the like, and consistent with conventional pharmaceutical
practices.
[0133] For instance, for oral administration in the form of a
tablet or capsule, the active drug component can be combined with
an oral, non-toxic, pharmaceutically acceptable, inert carrier such
as lactose, starch, sucrose, glucose, methyl callulose, magnesium
stearate, dicalcium phosphate, calcium sulfate, mannitol, sorbitol
and the like; for oral administration in liquid form, the oral drug
components can be combined with any oral, non-toxic,
pharmaceutically acceptable inert carrier such as ethanol,
glycerol, water, and the like. Moreover, when desired or necessary,
suitable binders, lubricants, disintegrating agents, and coloring
agents can also be incorporated into the mixture. Suitable binders
include starch, gelatin, natural sugars such as glucose or
beta-lactose, corn sweeteners, natural and synthetic gums such as
acacia, tragacanth, or sodium alginate, carboxymethylcellulose,
polyethylene glycol, waxes, and the like. Lubricants used in these
dosage forms include sodium oleate, sodium stearate, magnesium
stearate, sodium benzoate, sodium acetate, sodium chloride, and the
like. Disintegrators include, without limitation, starch, methyl
cellulose, agar, bentonite, xanthan gum, and the like.
[0134] The compounds of the present invention can also be
administered in the form of liposome delivery systems, such as
small unilamellar vesicles, large unilamellar vesicles, and
multilamellar vesicles. Liposomes can be formed from a variety of
phospholipids, such as cholesterol, stearylamine, or
phosphatidylcholines.
[0135] Compounds of the present invention may also be coupled with
soluble polymers as targetable drug carriers. Such polymers can
include polyvinylpyrrolidone, pyran copolymer,
polyhydroxypropylmethacrylamide-ph- enol,
polyhydroxyethylaspartamidephenol, or polyethyleneoxidepolylysine
substituted with palmitoyl residues. Furthermore, the compounds of
the present invention may be coupled to a class of biodegradable
polymers useful in achieving controlled release of a drug, for
example, polylactic acid, polyglycolic acid, copolymers of
polylactic and polyglycolic acid, polyepsilon caprolactone,
polyhydroxy butyric acid, polyorthoesters, polyacetals,
polydihydropyrans, polycyanoacylates, and crosslinked or
amphipathic block copolymers of hydrogels.
[0136] Dosage forms (pharmaceutical compositions) suitable for
administration may contain from about 1 milligram to about 100
milligrams of active ingredient per dosage unit. In these
pharmaceutical compositions the active ingredient will ordinarily
be present in an amount of about 0.5-95% by weight based on the
total weight of the composition.
[0137] Gelatin capsules may contain the active ingredient and
powdered carriers, such as lactose, starch, cellulose derivatives,
magnesium stearate, stearic acid, and the like. Similar diluents
can be used to make compressed tablets. Both tablets and capsules
can be manufactured as sustained release products to provide for
continuous release of medication over a period of hours. Compressed
tablets can be sugar coated or film coated to mask any unpleasant
taste and protect the tablet from the atmosphere, or enteric coated
for selective disintegration in the gastrointestinal tract.
[0138] Liquid dosage forms for oral administration can contain
coloring and flavoring to increase patient acceptance.
[0139] In general, water, a suitable oil, saline, aqueous dextrose
(glucose), and related sugar solutions and glycols such as
propylene glycol or polyethylene glycols are suitable carriers for
parenteral solutions. Solutions for parenteral administration
preferably contain a water soluble salt of the active ingredient,
suitable stabilizing agents, and if necessary, buffer substances.
Antioxidizing agents such as sodium bisulfite, sodium sulfite, or
ascorbic acid, either alone or combined, are suitable stabilizing
agents. Also used are citric acid and its salts and sodium EDTA. In
addition, parenteral solutions can contain preservatives, such as
benzalkonium chloride, methyl- or propyl-paraben, and
chlorobutanol.
[0140] Suitable pharmaceutical carriers are described in
Remington's Pharmaceutical Sciences, Mack Publishing Company, a
standard reference text in this field.
[0141] Representative useful pharmaceutical dosage-forms for
administration of the compounds of this invention can be
illustrated as follows:
[0142] Capsules
[0143] A large number of unit capsules can be prepared by filling
standard two-piece hard gelatin capsules each with 100 milligrams
of powdered active ingredient, 150 milligrams of lactose, 50
milligrams of cellulose, and 6 milligrams magnesium stearate.
[0144] Soft Gelatin Capsules
[0145] A mixture of active ingredient in a digestable oil such as
soybean oil, cottonseed oil or olive oil may be prepared and
injected by means of a positive displacement pump into gelatin to
form soft gelatin capsules containing 100 milligrams of the active
ingredient. The capsules should be washed and dried.
[0146] Tablets
[0147] Tablets may be prepared by conventional procedures so that
the dosage unit is 100 milligrams of active ingredient, 0.2
milligrams of colloidal silicon dioxide, 5 milligrams of magnesium
stearate, 275 milligrams of microcrystalline cellulose, 11
milligrams of starch and 98.8 milligrams of lactose. Appropriate
coatings may be applied to increase palatability or delay
absorption.
[0148] Injectable
[0149] A parenteral composition suitable for administration by
injection may be prepared by stirring 1.5% by weight of active
ingredient in 10% by volume propylene glycol and water. The
solution should be made isotonic with sodium chloride and
sterilized.
[0150] Suspension
[0151] An aqueous suspension can be prepared for oral
administration so that each 5 mL contain 100 mg of finely divided
active ingredient, 200 mg of sodium carboxymethyl cellulose, 5 mg
of sodium benzoate, 1.0 g of sorbitol solution, U.S.P., and 0.025
mL of vanillin.
[0152] Where the compounds of this invention are combined with
other anticoagulant agents, for example, a daily dosage may be
about 0.1 to 100 milligrams of the compound of Formula I and about
1 to 7.5 milligrams of the second anticoagulant, per kilogram of
patient body weight. For a tablet dosage form, the compounds of
this invention generally may be present in an amount of about 5 to
10 milligrams per dosage unit, and the second anti-coagulant in an
amount of about 1 to 5 milligrams per dosage unit.
[0153] Where the compounds of Formula I are administered in
combination with an anti-platelet agent, by way of general
guidance, typically a daily dosage may be about 0.01 to 25
milligrams of the compound of Formula I and about 50 to 150
milligrams of the anti-platelet agent, preferably about 0.1 to 1
milligrams of the compound of Formula I and about 1 to 3 milligrams
of antiplatelet agents, per kilogram of patient body weight.
[0154] Where the compounds of Formula I are adminstered in
combination with thrombolytic agent, typically a daily dosage may
be about 0.1 to 1 milligrams of the compound of Formula I, per
kilogram of patient body weight and, in the case of the
thrombolytic agents, the usual dosage of the thrombolyic agent when
administered alone may be reduced by about 70-80% when administered
with a compound of Formula I.
[0155] Where two or more of the foregoing second therapeutic agents
are administered with the compound of Formula I, generally the
amount of each component in a typical daily dosage and typical
dosage form may be reduced relative to the usual dosage of the
agent when administered alone, in view of the additive or
synergistic effect of the therapeutic agents when administered in
combination.
[0156] Particularly when provided as a single dosage unit, the
potential exists for a chemical interaction between the combined
active ingredients. For this reason, when the compound of Formula I
and a second therapeutic agent are combined in a single dosage unit
they are formulated such that although the active ingredients are
combined in a single dosage unit, the physical contact between the
active ingredients is minimized (that is, reduced). For example,
one active ingredient may be enteric coated. By enteric coating one
of the active ingredients, it is possible not only to minimize the
contact between the combined active ingredients, but also, it is
possible to control the release of one of these components in the
gastrointestinal tract such that one of these components is not
released in the stomach but rather is released in the intestines.
One of the active ingredients may also be coated with a material
which effects a sustained-release throughout the gastrointestinal
tract and also serves to minimize physical contact between the
combined active ingredients. Furthermore, the sustained-released
component can be additionally enteric coated such that the release
of this component occurs only in the intestine. Still another
approach would involve the formulation of a combination product in
which the one component is coated with a sustained and/or enteric
release polymer, and the other component is also coated with a
polymer such as a lowviscosity grade of hydroxypropyl
methylcellulose (HPMC) or other appropriate materials as known in
the art, in order to further separate the active components. The
polymer coating serves to form an additional barrier to interaction
with the other component.
[0157] These as well as other ways of minimizing contact between
the components of combination products of the present invention,
whether administered in a single dosage form or administered in
separate forms but at the same time by the same manner, will be
readily apparent to those skilled in the art, once armed with the
present disclosure.
[0158] Numerous modifications and variations of the present
invention are possible in light of the above teachings. It is
therefore to be understood that within the scope of the appended
claims, the invention may be practiced otherwise than as
specifically described herein.
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