Abstract: Five steroidal chemical compounds were isolated from the fresh rhizomes of Dioseorea zingiberensis Wright gathered from Sichuan Province. Their chem ieal structures have been elucidated as diosgenin palmitate [Ⅰ]; β-sitosterol [Ⅱ]; gra- cillin [Ⅲ]; protogracillin [Ⅳ] and 3-O-{α-L-rhamnopyranosyl (1→3)-[β-D-glucopy- ranosyl (1→2)]-β-D-glucopyranosyl}-26-O-{β-D-glucopyranosyl}-diosgenin [Ⅴ]. [Ⅴ]is a new steroidal saponin, named protozingiberensissaponin.

Key words: Dioscorea zingiberensis Wright, Steroidal saponin, Protogracillin, Protozingiberensissaponin