A pair of new diarylheptanoid enantiomers from bulbils of Dioscorea opposite Thunb.

Nine compounds were isolated and identified as (±)-diosniponol G (1), neo-olivil (2), isolariciresinol (3), bombasin (4), isoschaftoside (5), saponarin (6), apigenin 6-C-α-L-arabinopyranosyl-7-O-β-D-glucopyranoside (7), 2-hydroxy-3, 5, 7-trimethoxy-9, 10-dihydrophenanthrene (8), and albibrissinoside B (9) from bulbils of Dioscorea opposite Thunb. by multiple column chromatographic methods including Diaion HP-20, MCI gel CHP-20, and Sephadex LH-20. Compound 1 was a new pair of diarylheptanoid enantiomers, and the other compounds were isolated from D. opposite for the first time. The α-glucosidase inhibitory activities of the isolates were screened, and no compound exhibited significantly inhibitory activity against α-glucosidase at the concentration of 100 μmol·L^-1.