SYNTHESIS AND INHIBITORY ACTIVITIES ON PLATELET-AGGREGATION OF SOME FLAVONOID ANALOGS

A series of 26 benzodioxan and benzodioxol derivatives of flavone have been prepared. The activity of the compounds on washed human platelet aggregation induced by adenosine diphosphate (ADP, 5 mu mol/l), colla gen (10 mu g/ml) and calcimycin (20 mu mol/l) was evaluated. The alkox ycarbonyl side chain derivatives inhibited all three types of aggregat ion inducers. Among the tested compounds 1a is the most potent inhibit or of collagen-induced aggregation but possesses a weak activity again st the other t,wo used inducers. The esters IIIb and in particular, II Ic are active against all the three used inducers. These results sugge st that ethoxycarbonyl group is a potent substituent to provide the an tiplatelet action in this series of flavonoids.