SAPONINS FROM VIETNAMESE GINSENG, PANAX-VIETNAMENSIS HA-ET-GRUSHV COLLECTED IN CENTRAL VIETNAM .3.

Five new dammarane saponins derived from four new aglycones were isola ted from the rhizomes and roots of Panax vietnamensis HA et GRUSHV. On the basis of physicochemical and spectral evidence, the structures of these compounds were established as 6-O-beta-D-glucopyranosyl -epoxyd ammarane-3beta,6alpha,12beta,24alpha-tetrol (1), beta-D-xylopyranosyl- (1-->2)-beta-D-glucopyranosyl -epoxydammarane-3beta,6alpha,12beta,24al pha-tetrol (2), 6-O-beta-D-glucopyranosyl dammarane-3beta,6alpha,12bet a,20(S),24xi,25-hexol (5), -beta-D-glucopyranosyl]-20-O-beta-D-glucopy ranosyl dammarane-3beta,12beta,20(S),24xi,25-pentol (8) and beta-D-xyl opyranosyl-(1-->2)-beta-D-glucopyranosyl -epoxydammarane-3beta,6alpha, 12beta,25xi,26-pentol (10). The trivial names, vina-ginsenoside-R10, - R11, -R12, -R13 and -R14, respectively, were assigned to the new sapon ins.