STUDIES ON THE CONSTITUENTS OF CLEMATIS SPECIES .6. THE CONSTITUENTS OF CLEMATIS STANS SIEB ET ZUCC

From the roots of Clematis stans three new oleanane-type triterpenoid saponins named clemastanoside A, B and C, and two new lignan glycoside s named clemastanin A and B, have been isolated together with three kn own triterpenoid saponins, huzhangoside B, C and D, and three known li gnan glycosides, (+)-lariciresinol 4-O-beta-D-glucopyranoside, (+)-lar iciresinol 4'-O-beta-D-glucopyranoside and (+)-pinoresinol 4,4'-O-bis- beta-D-glucopyranoside. In addition, from the leaves, four new oleanan e-type triterpenoid saponins, named clemastanoside D, E, F and G have been isolated together with five known triterpenoid saponins, hederasa ponin B, kizutasaponin K-12, huzhangoside B, sieboldianoside B and huz hangoside D, and three known flavonoids, isoquercitrin, rutin and quer cetin 3-O-beta-D-glucuronopyranoside. The structures of the new compou nds were elucidated based on chemical and physicochemical evidence as follows: clemastanoside A, ibopyranosyl-(1-->3)-alpha-L-rhamnopyranosy l-(1--> 2)-alpha-L-arabinopyranosyl oleanolic acid eta-D-glucopyranosy l-(1-->6)-beta-D-glucopyranosyl ester (terminal rhamnosyl 4-O-acetate of huzhangoside B); clemastanoside B and C, 3-O-beta-D-xylopyranosyl- and -L-rhamnopyranosyl-(1-->2)-beta-D-galactopyranosyl oleanolic acid eta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, respectively ; clemastanoside D, L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl hederagenin 28-O-beta-D-glucopyranosyl ester; clemastanoside E, F and G, terminal rhamnosyl 4-O-, 3-O- and 2-O-acetate of L-rhamnopyranosyl -(1-->2)-alpha-L-arabinopyranosyl hederagenin eta-D-glucopyranosyl-(1- ->6)-beta-D-glucopyranosyl ester, respectively; clemastanin A, thoxy-3 ',4,9,9'-tetrahydroxy-4',7-epoxy-5,8-lignan 3'O-beta-D-glucopyranoside ; clemastanin B, +)-lariciresinol4,4'-O-bis-beta-D-glucopyranoside.