Constituents of Chinese Crude Drug"Wujiapi."III. On the Structure of Glycoside G and K of Bei-Wujiapi

The chemical structure of glycoside G (I), C36H56O13, mp 232-233°, [α]19D+30.2°(EtOH) and glycoside K (V), C40H66O16, mp 240-241°, [α]20D -27.58°(MeOH) were isolated from Bei-Wujiapi (cortex of Periploca sepium BGE.) and established to be periplocin and Δ5-pregnene-3β, 20α-diol(20)-β-D-glucopyranosyl (1glu→6glu)-β-D-glucopyranosyl (1glu→2dig)-β-D-digitalopyranoside. It should be noted that glycoside K is the first example of the pregnane type glycoside whose sugar moiety links to the hydroxyl group other than C3-hydroxyl group of the steroidal aglycone.