Saponins from Leaves of Kalopanax septemlobus (THUNB.) KOIDZ. : Structures of Kalopanax-saponins La, Lb and Lc

Abstract

From leaves of Kalopanax septemlobus (THUNB.) KOIDZ., three new saponins named kalopanax-saponins La (6), Lb (7) and Lc (8) were isolated together with five known saponins, kalopanax-saponins A and B, akeboside Stb, eleutheroside K and saponin Pg. The new sapogenin 9 named kalopanax-genin L1, which is common to 6, 7 and 8, was formulated as 22α-hydroxyhederagenin. On the basis of chemical and spectral data, the structures of these saponins were elucidated as follows : 3-O-α-L-arabinopyranosyl-22α-hydroxyhederagenin (6), 3-O-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-22α-hydroxyhederagenin (7) and 3-O-β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl-22α-hydroxyhederagenin (8).