Antithrombotic agents

Drug – bio-affecting and body treating compositions – Designated organic active ingredient containing – Having -c- – wherein x is chalcogen – bonded directly to...

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C514S443000, C548S187000, C548S229000, C548S254000, C548S203000, C548S311400, C548S518000, C548S523000, C548S525000

Reexamination Certificate

active

06350774

ABSTRACT:

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 A&agr;-chains and the B&bgr;-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. 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 amount of a thrombin inhibiting compound of formula I (or a pharmaceutically acceptable salt thereof)
wherein
A is carbonyl or methylene;
D is CH, CR
d
or N in which R
d
is hydroxy, methyl or methoxy;
E is CH, CR
e
or N in which R
e
is methyl, methoxy or halo;
R
2
is —X
2
—(CH
2
)
m
—NR
a
R
b
in which X
2
is a direct bond, methylene, O or S; m is 1, 2, 3, 4 or 5; provided that when m is 1, then X
2
is a direct bond; and R
a
and R
b
are independently hydrogen or (1-3C)alkyl or the group NR
a
R
b
is pyrrolidino, piperidino, or morpholino;
R
3
is —X
3
—(CH
2
)
n
—L—R
c
, —O—CHR
f
—CHR
f
—R
c
, —O—N(R
g
)
2
, —S—R
h
or —CO—R
i
in which X
3
is a direct bond, methylene or O; n is 1 or 2, provided that when n is 1, then X
2
is a direct bond; L is —(CH
2
)
k
— in which k is 0, 1, 2 or 3, or L is —(CHCH
3
)—; R
c
is cyano, cyclopentyl, 2-oxopyrrolidin-1-yl, 2,5-dioxopyrrolidin-1-yl, 2-oxooxazolidin-3-yl, 2-oxoimidazolidin-1-yl, 3-methyl-2-oxoimidazolidin-1-yl, 2-oxopyrrolidin-3-yl, 1-methyl-2-oxopyrrolidin-3-yl, 1-tetrazolyl, methoxy, methylsulfonylamino or phenylsulfonylamino; or R
c
is 2-methylthiazol-4-yl, CONR
j
R
k
or CONHNR
j
R
k
in which R
j
is hydrogen, methyl or ethyl and R
k
is hydrogen, methyl, ethyl or isopropyl; the two R
f
groups together form a tetramethylene diradical so that the resulting 1,2-cyclohexanediyl group is trans; R
g
is methyl or ethyl, R
h
is 2-thiazolyl; and R
i
is methoxy, dimethylamino or pyrrolidino; and
R
6
is hydrogen, hydroxy or methoxy.
A particular thrombin inhibiting compound of formula I (or a pharmaceutically acceptable salt thereof) as described above is one wherein
A is carbonyl or methylene;
D is CH, CR
d
or N in which R
d
is methyl or methoxy;
E is CH, CR
e
or N in which R
e
is methyl, methoxy or halo;
R
2
is —X
2
—(CH
2
)
m
—NR
a
R
b
in which X
2
is a direct bond, methylene, O or S; m is 1, 2, 3, 4 or 5; provided that when m is 1, then X
2
is a direct bond; and R
a
and R
b
are independently hydrogen or (1-3C)alkyl or the group NR
a
R
b
is pyrrolidino, piperidino, or morpholino;
R
3
is —X
3
—(CH
2
)
n
—R
c
, —O—CHR
f
—CHR
f
—R
c
, —O—N(R
g
)
2
, —S—R
h
or —CO—R
i
in which X
3
is a direct bond, methylene or O; n is 1 or 2, provided that when n is 1, then X
2
is a direct bond; R
c
is cyano, cyclopentyl, 2-oxopyrrolidin-1-yl, 2,5-dioxopyrrolidin-1-yl, 2-oxooxazolidin-3-yl, 2-oxoimidazolidin-1-yl, 3-methyl-2-oxoimidazolidin-1-yl, 2-oxopyrrolidin-3-yl, 1-methyl-2-oxopyrrolidin-3-yl, 1-tetrazolyl, methoxy, methylsulfonylamino or phenylsulfonylamino; the two R
f
groups together form a tetramethylene diradical so that the resulting 1,2-cyclohexanediyl group is trans; R
g
is methyl or ethyl, R
h
is 2-thiazolyl; and R
i
is methoxy, dimethylamino or pyrrolidino; and
R
6
is hydrogen, hydroxy or methoxy.
A particular value for D is CH.
A particular value for E is —CR
e
in which R
e
is methyl or methoxy.
A particular value for R
2
is 2-(1-pyrrolidinyl)-ethoxy.
A particular value for R
3
is —X
3
—(CH
2
)
n
—R
c
in which R
c
is 2-oxopyrrolidin-1-yl, and more particularly in which R
3
is (2-oxopyrrolidin-1-yl)methyl or 2-(2-oxopyrrolidin-1-yl)ethoxy.
A particular value for R
6
is hydroxy.
A more particular value for A is methylene.
A preferred method of the invention includes one wherein said compound of formula I is one of those described herein at Examples 1, 13, 22 and 23.
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 I also may serve as a prodrug for a different thrombin inhibitin

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Antithrombotic agents does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Antithrombotic agents, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Antithrombotic agents will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-2957369

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.