Phytochemical Constituents of Amomum xanthioides

Seven monoterpenes, three sesquiterpenes, three phenolics and one flavonoid were isolated from the MeOH extract of Amomum xanthioides. Their structures were determined by spectroscopic methods to be caryophyllene oxide (1), bornyl acetate (2), nerolidol (3), spathulenol (4), (-)-borneol (5), (+)-5-endohydroxycamphor (6), vanillic acid (7), protocatechuic acid methyl ester (8), betulabuside A (9), (1R,4S,6R)-6-hydroxyfenchan-2-one-6-O--D-glucopyranoside (10), (1S,4R,6S)-6-hydroxybornan-2-one-6-O--D-glucopyranoside (11), (1R,2S,4S,5R)-angelicoidenol 2-O--D-glucopyranoside (12), 1-O-vanilloyl--D-glucopyranoside (13), and quercetin-3-rhamnopyranoside (14). Compounds 6-14 were isolated for the first time from this plant source. Compounds 3 and 4 exhibited moderate cytotoxicity against four human cancer cell lines in vitro using a SRB bioassay.