Aristolactams and dioxoaporphines from Fissistigma balansae and Fissistigma oldhamii.

Investigation of extracts of Fissistigma balansae and Fissistigma oldhamii resulted in the isolation of 11 aristolactams-stigmalactam (1), piperolactam A (2), piperolactam C (3), aristolactam AII (4), aristolactam AIIIa (5), aristolactam BII (6), aristolactam BIII (7), aristolactam FII (8), goniothalactam (9), enterocarpam I (10), and velutinam (11)-as well as two dioxoaporphines, noraristolodione (12) and norcepharadione B (13). The new compound 1 was identified by spectral data interpretation. Compounds 1-13 were subjected to antiplatelet aggregation testing.