Dihydrostilbene glycosides from var. assamica and their cytotoxic activity.

Three undescribed dihydrostilbene glycosides, 3,5-dihydroxyldihydrostilbene 4'--[6''--(4'''-hydroxylbenzoyl)]--D-glucopyranoside (), 3,5-dihydroxyldihydrostilbene 4'--(6''--galloyl)--D-glucopyranoside (), and 3,5-dihydroxyldihydrostilbene 4'--[6''--(3''',4'''-dimethoxyl)galloyl]--D-glucopyranoside (), and seven known compounds, kaempferol 3---D-glucopyranoside (), isoquercitrin (), kaempferol 3--L-rhamnoside (), quercitrin (, (6,9)-roseoside (), (-)-epicatechin 3--gallate (), and (-)-epigallocatechin 3--gallate () have been isolated from the methanol extract of the leaves of var. (J.W.Mast.) Kitam. (synnonym of (Mast.) H.T.Chang) (Theaceae). Their structures were elucidated by spectroscopic methods (1 D-, 2 D-NMR) and mass spectra. All compounds were evaluated for cytotoxic activity against human oral cancer (CAL27) and human breast cancer (MDAMB231) cell lines. Compound showed significant cytotoxic activity against CAL27 and MDAMB231 cell lines with IC values of 9.78 ± 0.25 and 3.27 ± 0.18 μM, respectively, compared to those of positive control, capecitabine (IC values of 8.20 ± 0.75 and 5.20 ± 0.89 μM).