Antiplatelet activity of BRX-018, (6aS,cis)-malonic acid 3-acetoxy-6a9-bis-(2-methoxycarbonyl-acetoxy)-6,6a,7,11b-tetrahydro-indeno[2,1-c]chromen-10-yl ester methylester.

Brazilin (7,11b-dihydrobenz[b]indeno[1,2-d]pyran-3,6a,9,10 (6H)-tetrol), the major component of Caesalpinia sappan L., was reported to show antiplatelet activity through the inhibition of phospholipase A2 (PLA2) activity and the increase in intracellular free Ca2+ concentration ([Ca2+]i). To search more potential antiplatelet agent, brazilin derivatives were synthesized and examined for their effects on the platelet aggregation.