Prostaglandin, analogue platelet aggregation inhibitor

Tapazole methimazole. taprostene [inn] (CG 4203) is a prostaglandin and synthetic analogue of prostacyclin (PGI2). It is a prostanoid RECEPTOR AGONIST that iS a PLATELET AGGREGATION INHIBITOR and claimed to be cardioprotective. 

Some 1,5-disubstituted imidazoles have been found to exhibit potent inhibitory activity against platelet aggregation and as thromboxane synthetase inhibitors. Hence synthesis of imidazole analogues of prostaglandin require 1,5-orientation. Good yields of these desired isomers are obtained when 4-/-butyldimethylsilyloxymethylimidazole is treated in succession with butyllithium and an... 

Hydantoins and other imidazole analogues of prostaglandins of type 146 and 147 have been synthesized as racemic compounds.355 The less polar diastereoisomer of 146b is a potent inhibitor of platelet aggregation in human platelet-rich plasma. 

A number of 7 oxabicyclo[2.2.1]heptane prostaglandin analogues were synthesized and evaluated as potential thromboxane synthetase inhibitors or thromboxane antagonists. Several of the compounds tested were shown to be TXA2 antagonists, judged from platelet aggregation and thromboxane inhibition tests. Two of the compounds also inhibited arachidonic acid induced bronchoconstriction [266]. 

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