抄録
New saponins, named gypenosides XV (1), XVI (2), XVII (3), XVIII (4), XIX (5), XX (6) and XXI (7) were isolated from Gynostemma pentaphyllum MAKINO. On enzymatic hydrolysis, 1, 2, and 3 yielded 20-O-β-D-glucopyranoside of 20 (S)-protopanaxadiol (compound K) (8), and 4, 5, 6 and 7 afforded 20-O-β-D-glucopyranoside of dammar-24-ene-3β, 12β, 20 (S), 26-tetraol (9) as a prosapogenin. The configuration of the sugar linkages in each saponin was established on the basis of chemical and spectroscopic evidence.
