Studies on the Constituents of Hedera rhombea BEAN. IV. On the Hederagenin Glycosides. (2)

Abstract

On the basis of chemical and physicochemical evidence, the structures of two new hederagenin bisdesmosides, named Kizuta saponins K₈ (X) and K₁₁ (I), which were isolated from the stem and bark of Hedera rhombea BEAN (Araliaceae), were established to be as follows : X, 3-O-α-L-arabinopyranosyl-hederagenin 28-O-α-L-rhamnopyranosyl-(1→4)-6-O-acetyl-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester ; I, 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-hederagenin 28-O-α-L-rhamnopyranosyl (1→4)-6-O-acetyl-β-D-glucopyranosyl-(1→6)-β-D-glucopyranosyl ester. A glucoside mixture (XIII) was considered to be a mixture of the β-D-glucopyranosides of campesterol (trace), stigmasterol and β-sitosterol based on chemical and physicochemical evidence.