Chemical constituents from Mucuna membranacea

Antiplatelet-directed fractionation of the ethanolic extract from the root of Mucuna membranacea Hayata resulted in the isolation of friedelin (1), friedelanol (2), beta-sitosterol (3a) & stigmasterol (3b), trans-p-coumaric acid (4), protocatechuic acid (5), vanillic acid (6), and flavonoids -- geraldol (7), 3'-methoxydaidzein (8), genistein (9), daidzein (10), cyclosin (11), formononetin (12), orbol (13), isoformononetin (14), pratensein (15) and luteolin (16). Their structures were elucidated on the basis of spectral methods. Compounds 7 and 8 were tested for the antiplatelet aggregation activity and appeared to be specific against collagen-induced platelet aggregation with a IC50 values of 61.5 and 12.3 mu M, respectively.