Studies on the Constituents of Cucurbitaceae Plants. XI. On the Saponin Constituents of Gynostemma pentaphyllum MAKINO (7)

Abstract

New saponins, named gypenosides XLII (1), XLIII (2), XLIV (3), XLV (4) and XLVI (5), besides the known gynosaponin TN-1 (6), -2 (7), gypenoside I (8), II (9), V (10) and VII (11) were isolated from the aerial parts of Gynostemma pentaphyllum MAKINO collected in Tokushima pref. On enzymatic hydrolysis 1, 2, 3, 4 and 5 yielded 20-O-β-D-glucopyranoside of dammar-24-ene-2α, 3β, 12β, 20 (S)-tetraol (6) as a prosapogenin. The configuration of the sugar linkages in each saponin was established on the basis of chemical and spectroscopic evidence.