Flavan-4-ol Glycosides from the Rhizomes of Abacopteris penangiana.

Four new flavan-4-ol glycosides, abacopterins A-D (1-4), were isolated from a methanol extract of the rhizomes of Abacopteris penangiana, together with two known compounds, triphyllin A (5) and 6,8-dimethyl-7-hydroxy-4'-methoxyanthocyanidin-5-O-beta-D-glucopyranoside (6). Their structures were elucidated by extensive spectroscopic analysis and chemical methods. The cytotoxic activity of 1-5 against HepG2 human hepatoma cells was investigated.