Immtmological-adjuvant saponins from the roots of Panax notoginseng

The total saponin extract from the dried roots of Panax notoginseng (BURK.) F. H. CHEN possesses immunological-adjuvant activities. Guided by in vivo immunological tests, further study on this fraction afforded three active dammarane-type saponins. Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods, including 1D- and 2D-NMR. The novel compound (20S)-protopanaxatriol 20-O-beta-D-glucopyranosyl-(1 -> 6)-beta-D-glueopyranoside (1), and the two known compounds ginsenoside Rh, (2) and notoginsenoside K (3) exhibited immunological-adjuvant activities on the humoral immune responses of ICR mice against ovalbumin (OVA).