MEDICINAL FOODSTUFFS - XIII - SAPONIN CONSTITUENTS WITH ADJUVANT ACTIVITY FROM HYACINTH BEAN, THE SEEDS OF DOLICHOS-LABLAB L. (2) - STRUCTURES OF LABLABOSIDE-D, LABLABOSIDE-E, AND LABLABOSIDE-F

Following the characterization of lablabosides A, B, and C, new oleana ne-type triterpene bisdesmosides, lablabosides D, E, and F, were isola ted from the glycosidic fraction with adjuvant activity obtained from the seeds of Dolichos lablab L. (Leguminosae). Their chemical structur es were elucidated on the basis of chemical and physicochemical eviden ce as follows : 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyr anosyl (1-->2)-beta-D-glucopyranosiduronic -hydroxy-3-methylglutaroyl) -beta-D-glucopyranosyl] 24-epi-hederagenin (lablaboside D), 3-O-[alpha -L-rhamnopyranosyl (1-->2)-beta-D-galactopyranosyl (1-->2)-beta-D-gluc opyranosiduronic acid]-28-O-[alpha-L-rhamnopyranosyl (1-->4)-alpha-L-r hamnopyranosyl (1-->2)-beta-D-glycopyranosyl] 24-epi-hederagenin (labl aboside E), 3-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-galactopyranos yl (1-->2)-beta-D-glucopyranosiduronic acid]-28-O-[alpha-L-rhamnopyran osyl (1-->4)-alpha-L-rhamnopyranosyl (1-->2)-beta-glucopyranosyl] olea nolic acid (lablaboside F).