Vitronectin receptor antagonists

Details Vitronectin receptor antagonists Vitronectin receptor antagonists

2000-04-18

2001-02-20

Davis, Zinna Northington (Department: 1625)

Organic compounds -- part of the class 532-570 series

Organic compounds

Carboxylic acid esters

Reexamination Certificate

active

06191304

ABSTRACT:

FIELD OF THE INVENTION
This invention relates to pharmaceutically active compounds which inhibit the vitronectin receptor and are useful for the treatment of inflammation, cancer and cardiovascular disorders, such as atherosclerosis and restenosis, and diseases wherein bone resorption is a factor, such as osteoporosis.
BACKGROUND OF THE INVENTION
Integrins are a superfamily of cell adhesion receptors, which are transmembrane glycoproteins expressed on a variety of cells. These cell surface adhesion receptors include gpIIb/IIIa (the fibrinogen receptor) and &agr;
&ngr;
&bgr;
3
(the vitronectin receptor). The fibrinogen receptor gpIIb/IIa is expressed on the platelet surface, and mediates platelet aggregation and the formation of a hemostatic clot at the site of a bleeding wound. Philips, et al.,
Blood.,
1988, 71, 831. The vitronectin receptor &agr;
&ngr;
&bgr;
3
is expressed on a number of cells, including endothelial, smooth muscle, osteoclast, and tumor cells, and, thus, it has a variety of functions. The &agr;
&ngr;
&bgr;
3
receptor expressed on the membrane of osteoclast cells mediates the adhesion of osteoclasts to the bone matrix, a key step in the bone resorption process. Ross, et al.,
J. Biol. Chem.,
1987, 262, 7703. A disease characterized by excessive bone resorption is osteoporosis. The &agr;
&ngr;
&bgr;
3
receptor expressed on human aortic smooth muscle cells mediates their migration into neointima, a process which can lead to restenosis after percutaneous coronary angioplasty. Brown, et al.,
Cardiovascular Res.,
1994, 28, 1815. Additionally, Brooks, et al.,
Cell,
1994, 79, 1157 has shown that an &agr;
&ngr;
&bgr;
3
antagonist is able to promote tumor regression by inducing apoptosis of angiogenic blood vessels. Thus, agents that block the vitronectin receptor would be useful in treating diseases, such as osteoporosis, restenosis and cancer.
The vitronectin receptor is now known to refer to three different integrins, designated &agr;
&ngr;
&bgr;
1
, &agr;
&ngr;
&bgr;
3
and &agr;
&ngr;
&bgr;
5
Horton, et al.,
Int. J. Exp. Pathol.,
1990, 71, 741. &agr;
&ngr;
&bgr;
1
binds fibronectin and vitronectin. &agr;
&ngr;
&bgr;
3
binds a large variety of ligands, including fibrin, fibrinogen, laminin, thrombospondin, vitronectin, von Willebrand's factor, osteopontin and bone sialoprotein I. &agr;
&ngr;
&bgr;
5
binds vitronectin. The vitronectin receptor &agr;
&ngr;
&bgr;
5
has been shown to be involved in cell adhesion of a variety of cell types, including microvascular endothelial cells, (Davis, et al.,
J. Cell. Biol.,
1993, 51, 206), and its role in angiogenesis has been confirmed. Brooks, et al.,
Science,
1994, 264, 569. This integrin is expressed on blood vessels in human wound granulation tissue, but not in normal skin.
The vitronectin receptor is known to bind to bone matrix proteins which contain the tri-peptide Arg-Gly-Asp (or RGD) motif. Thus, Horton, et al.,
Exp. Cell Res.
1991, 195, 368, disclose that RGD-containing peptides and an anti-vitronectin receptor antibody (23C6) inhibit dentine resorption and cell spreading by osteoclasts. In addition, Sato, et al.,
J. Cell Biol.
1990, 111, 1713 discloses that echistatin, a snake venom peptide which contains the RGD sequence, is a potent inhibitor of bone resorption in tissue culture, and inhibits attachment of osteoclasts to bone.
It has now been discovered that certain compounds are potent inhibitors of the &agr;
&ngr;
&bgr;
3
and &agr;
&ngr;
&bgr;
5
receptors. In particular, it has been discovered that such compounds are more potent inhibitors of the vitronectin receptor than the fibrinogen receptor.
SUMMARY OF THE INVENTION
This invention comprises compounds as described hereinafter, which have pharmacological activity for the inhibition of the vitronection receptor and are useful in the treatment of inflammation, cancer and cardiovascular disorders, such as atherosclerosis and restenosis, and diseases wherein bone resorption is a factor, such as osteoporosis.
This invention is also a pharmaceutical composition comprising compounds as described hereinafter and a pharmaceutically carrier.
This invention is also a method of treating diseases which are mediated by the vitronectin receptor. In a particular aspect, the compounds of this invention are useful for treating atherosclerosis, restenosis, inflammation, cancer and diseases wherein bone resorption is a factor, such as osteoporosis.
DETAILED DESCRIPTION
This invention comprises novel compounds which are more potent inhibitors of the vitronectin receptor than the fibrinogen receptor. The novel compounds comprise a dibenzocycloheptene core in which a nitrogen-containing substituent is present on one of the aromatic six-membered rings of the dibenzocycloheptene and an aliphatic substituent containing an acidic moiety is present on the seven-membered ring of the dibenzocycloheptene. The dibenzocycloheptene ring system is believed to orient the substituent sidechains on the six and seven membered rings so that they may interact favorably with the vitronectin receptor. It is preferred that about twelve to fourteen intervening covalent bonds via the shortest intramolecular path will exist between the acidic group on the aliphatic substituent of the seven-membered ring of the dibenzocycloheptene and the nitrogen of the nitrogen-containing substituent on one of the aromatic six-membered ring of the dibenzocycloheptene.
Specific compounds of this invention are:
(±)-10,11-Dihydro-3-[3-(4-amino-2-pyridylamino)-1-propyloxy]-5H-dibenzo[a,d]cycloheptene-10-acetic acid;
(±)-10,11-Dihydro-3-[2-[6-(ethylamino)-2-pyridyl]-1-ethoxy]-5H-dibenzo[a,d]cycloheptene-10acetic acid; and
(±)-10,11-Dihydro-3-[3-(4-methyl-2-pyridylamino)-1-propyloxy]-5H-dibenzo[a,d]cycloheptene-10-acetic acid;
or pharmaceutically acceptable salts thereof.
In cases wherein the compounds of this invention may have one or more chiral centers, unless specified, this invention includes each unique nonracemic compound which may be synthesized and resolved by conventional techniques.
Also included in this invention are prodrugs of the compounds of this invention. Prodrugs are considered to be any covalently bonded carriers which release the active parent drug (compounds of the instant invention) in vivo.
The compounds of this invention inhibit the binding of vitronectin and other RGD-containing peptides to the vitronectin receptor. Inhibition of the vitronectin receptor on osteoclasts inhibits osteoclastic bone resorption and is useful in the treatment of diseases wherein bone resorption is associated with pathology, such as osteoporosis and osteoarthritis.
In another aspect, this invention is a method for stimulating bone formation which comprises administering a compound which causes an increase in osteocalcin release. Increased bone production is a clear benefit in disease states wherein there is a deficiency of mineralized bone mass or remodeling of bone is desired, such as fracture healing and the prevention of bone fractures. Diseases and metabolic disorders which result in loss of bone structure would also benefit from such treatment. For instance, hyperparathyroidism, Paget's disease, hypercalcemia of malignancy, osteolytic lesions produced by bone metastasis, bone loss due to immobilization or sex hormone deficiency, Behcet's disease, osteomalacia, hyperostosis and osteopetrosis, could benefit from administering a compound of this invention.
Additionally, since the compounds of the instant invention inhibit vitronectin receptors on a number of different types of cells, said compounds would be useful in the treatment of inflammatory disorders, such as rheumatoid arthritis and psoriasis, and cardiovascular diseases, such as atherosclerosis and restenosis. The compounds of the present invention may be useful for the treatment or prevention of other diseases including, but not limited to, thromboembolic disorders, asthma, allergies, adult respiratory distress syndrome, graft versu

Affiliated with

Also associated with

Rating

Vitronectin receptor antagonists does not yet have a rating. At this time, there are no reviews or comments for this patent.

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

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2610022