Abstract
Further investigation on the saponins of the flower-buds of Panax ginseng C. A. Meyer has resulted in the isolation and structural elucidation of a pair of new 24-epimers of dammarane type saponins named ginsenoside I and II. The structures of the epimers were characterized on the basis of chemical and spectral evidence as 3-O-[β-D-glucopyranosyl-(1 → 2)-β-D-glucopyranosyl]-20-S-O-β-D-glucopyranosyl-3β12β20(S)-trihydroxy-24ξ-hydroperoxydammar-25-ene, except for their C-24 configurations. Ginsenoside I is a new triterpene glycoside, and ginsenoside II is a known compound first isolated from a natural plant.