Two new steroidal saponins from the rhizomes of Dioscorea zingiberensis

AimTo investigate the chemical constituents of Dioscorea zingiberensis C. H. Wright.MethodsThe compounds were isolated by various chromatographic techniques, and the structures of the new steroidal saponins were elucidated by extensive 1D- and 2D-NMR, MS, and IR spectral analysis.ResultsThe 70% EtOH extract of the rhizomes of Dioscorea zingiberensis afforded two new steroidal saponins, zingiberenosides A (1) and B (2), along with eight known analogues, 3β, 26-dihydroxy-25(R)-furosta-Δ5, 20(22)-diene-3-O-α-L- rhamnopyranosyl-(1→2)-O-β-D-glucopyranoside (3), methyl parvifloside (4), deltoside (5), methyl deltoside (6), zingiberensis new saponin (7), deltonin (8), progenin III (9) and diosgenin-diglucoside (10).ConclusionTwo new steroidal saponins were isolated from Dioscorea zingiberensis and their structures determined.