Triterpenoid saponins of Acanthopanax nipponicus leaves

Five new triterpenoid saponins, nipponosides A-E (1, 3-6), were isolated fr om Acanthopanax nipponicus leaves, along with a known saponin, kalopanaxsap onin G (2). Nipponosides A-E were characterized as the 28-O-alpha-L-rhamnop yranosyl(1-->4)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester of 3-oxohederagenin, oleanolic acid 3-O-beta-D-glucopyranoside, gypsogenin 3- O-beta-D-glucopyranoside, 3 beta,23,29-trihydroxyolean-12-en-28-oic acid, a nd 3 beta,20 alpha,2 3-trihydroxy-30-nor-olean-12-en-28-oic acid, respectiv ely. The structures of these new compounds were based on chemical and spect ral methods.