Fargosides A - E, triterpenoid saponins from Holboellia fargesii

Abstract

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 were elucidated on the basis of chemical and physicochemical evidence and found to be 3β,20α- dihydroxy-29-norolean-12-en-28-oic acid 3-Ο-β- D-xylopyranosyl-(1→2)]-β-D-glucopyranoside (1), 3β,20α24-trihydroxy-29-norolean-12-en-28-oic acid 23-Ο-β-D-fucopyranosyl-(1→2)-[α-L-arabinopyranosyl- (1→3)]-β-D-glucopyranoside (2), 3β,23-dihydroxy-30-norolean-2,20(29)-dien-28-oic acid 3-Ο-α-L-arabinopyranosyl- (1→2)-[β-D-glucopyranosyluronic acid-(1→3)]-α-L-arabinopyranoside (3), 3β,23- dihydroxy-30-norolean-12,20(29)-dien-28-oic acid 3-Ο-methyl β- D-glucopyranosyluronate-(1→3)-α-L-arabinopyranoside (4), and 3β,23-dihydroxy-olean-12-en-28-oic acid 3-Ο-methyl β-D-glucopyranosyluronate-(1→3)-α-L-arabinopyranoside (5), respectively.