OBJECTIVETo isolate the bibenzyl derivatives from the tuber of Arundina graminifolia and evaluate the anti-tumor activity of these compounds in vitro.

METHODThe constituents have been extracted by 95% alcohol and then isolated by column chromatography on silica gel and Sephedax LH-20. The structures were determined by UV, IR, NMR and MS spectral analysis.

RESULTSix constituents have been isolated, and their structures have been established as 2,7-dihydroxy-1-(p-hydroxylbenzyl)-4-methoxy-9, 10-dihydrophenanthrene (1), 4,7-dihydroxy-1- (p-hydroxylbenzyl)-2-methoxy-9,10-dihydrophenanthrene (2), 3, 3'-dihydroxy-5-methoxybibenzyl (3), (2E) -2- propenoic acid-3-(4-hydroxy-3-methoxyphenyl) -tetracosyl ester (4), (2E) -2-propenoic acid-3- (4-hydroxy-3- methoxyphenyl) -pentacosyl ester (5) and pentadecyl acid (6), respectively.

CONCLUSIONAll compounds except for 3 were isolated from the tuber of A. graminifolia for the first time. Compound 3 with bibenzyl ring opening exhibits stronger anti-tumor activity than that of compounds 1 and 2 with bibenzyl ring closing.