Urea derivatives useful as platelet aggregation inhibitors

#1. Field of the Invention

#This invention pertains to urea derivatives which inhibit platelet aggregation in mammals.

#2. Related Art

#A preferred embodiment of the present invention is a compound of the formula I or a pharmaceutically acceptable salt thereof: wherein

#R is selected from the group consisting of hydrogen, lower alkyl radicals of 1 to about 6 carbon atoms, lower alkenyl radicals of 2 to about 8 carbon atoms, alicyclic hydrocarbon radicals of 3 to about 6 carbon atoms, monocyclic or bicyclic aromatic hydrocarbon radicals, and monocyclic or bicyclic heterocyclyl radical in which 1 to about 3 heteroatoms are independently selected from oxygen and nitrogen wherein all of said radicals are optionally substituted with hydroxyl, lower alkoxy, lower alkyl, halogen, nitro, carboxyl, and trifluoromethyl;

#W is selected from the group consisting of hydrogen, lower alkyl radicals of 1 to about 6 carbon atoms, lower alkenyl radicals of 2 to about 6 carbon atoms, alicyclic hydrocarbon radicals of 3 to about 6 carbon atoms, and aromatic hydrocarbon radicals of 6 to about 12 carbon atoms, wherein all of said radicals are optionally substituted with hydroxyl, lower alkoxy, lower alkyl, halogen, nitro, amino, and acyloxy;