Fargosides A-E, triterpenoid saponins from Holboellia fargesii

Five new triterpenoid saponins, fargosides A, B, C, D, and E, were isolated from the roots of Holboellia fargesii. The structures of fargosides A-E we re elucidated on the basis of chemical and physicochemical evidence and fou nd to be 3 beta ,20 alpha -dihydroxy-29-norolean-12-en-28-oic acid 3-O-beta -D-xylopyranosyl-(1 -->2)-beta -D-glucopyranoside (1), 3 beta ,20 alpha ,2 4-trihydroxy-29-norolean-12-en-28-oic acid 23-O-beta -D-fucopyranosyl-(1 -- >2)-[alpha -L-arabinopyranosyl-(1 -->3)]-beta-upsilon -glucopyranoside (2), 3,beta ,23-dihydroxy-30-norolean-2,20(29)-dien-28-oic acid 3-O-alpha -L-ar abinopyranosyl-(1 -->2)-[beta -D-glucopyranosyluronic acid-(1 -->3)]-alpha -L-arabinopyranoside (3), 3 beta ,23-dihydroxy-30-norolean-12,20(29)-dien-2 8-oic acid 3-O-methyl beta -D-glucopyranosyluronate-(1 -->3)-alpha -L-arabi nopyranoside (4), and 3 beta ,23-dihydroxy-olean-12-en-28-oic acid 3-O-meth yl beta -D-glucopyranosyluronate-(1 -->3)-alpha -L-arabinopyranoside (5), r espectively.