| abstract |
Pyrazolidinedione derivatives of the general formula (I), wherein R1 is hydrogen, optionally substituted alkyl, cycloalkyl, aryl, arylalkyl, heteroaryl, heteroarylalkyl or alkanoyl; and R2 is aryl or heteroaryl; tautomers thereof; geometric isomers thereof and tautomers of these geometri c isomers, including mixtures of individual compounds of formula (I), or tautomers thereof, and their geometric isomers, or tautomers thereof, pharmaceutically acceptable acid addition salts of compounds which are basic ; pharmaceutically acceptable salts of compounds containing acidic groups with bases; pharmaceutically acceptable esters of compounds containing hydroxy or carboxy groups; prodrugs of compounds in which a prodrug forming group is present; as well as hydrates or solvates thereof; are active as platelet adenosine diphosphate receptor antagonists and can be used for the preventio n and/or treatment of peripheral vascular, of visceral-, hepatic- and renal- vascular, of cardiovascular and of cerebrovascular diseases or conditions associated with platelet aggregation, particularly thrombosis, and, respectively, for the manufacture of corresponding medicaments. Some, albeit not all, of the compounds of the above formula (I) are novel. |