摘要:
Four new biflavonoids [pyranoamentoflavone 7,4"'-dimethyl ether (1), pyranoamentoflavone 7,4'-dimethyl ether (2), 6"-(3-methyl-2-butenyl)amentoflavone (8), and 6"-(2-hydroxy-3-methyl-3-butenyl)amentoflavone (4)], as well as three known biflavonoids, [pyranoamentoflavone (5a), amentoflavone (6), and 2,3-dihydroamentoflavone (7)] have been isolated from the leaves of Calophyllum venulosum. The structures of the new compounds were established by spectroscopic data and chemical modification.