A series of novel 2-aminopyrimidine and 2-Substituted-4,6-diaminopyrimidine derivatives have been synthesized and their antiplatelet aggregation activities were assessed against ADP and arachidonic acid-induced platelet aggregation in human plasma using light transmission aggregometry. Among the tested derivatives, compounds Ia, Ib, IB and II16 exhibited the highest antiplatelet aggregation activity (36.75, 72.4, 62.5 and 80 µM). None of the compounds showed satisfactory activity against the aggregation induced by ADP but acceptable activities were observed against the aggregation induced by arachidonic acid. 2- aminopyrimidines were more active than 4,6- diaminopyrimidines in this respect.
Keywords: 2-Substituted-4; 2-aminopyrimidines; 6-diaminopyrimidines; Antiplatelet aggregation.