CRYSTAL STRUCTURE OF (20R, 25S)-12β, 25-EPOXY-20, 26-CY-CLODAMMARANE-2α, 3β-DIOL MONOMETHANOL,C_(30)H_(50)O_3·CH_3OH

<正> Gypenosides, a series of dammarane-type saponins from Gynostemma pentaphyllum Makino, were hydrolyzed under 5％ H_2SO_4 catalysis to afford the title compound as a new secondary sapogenin in addition to panaxadiol and 2a-hydroxypanaxadiol. The crystals of the title compound were obtained from methanol solution and a colourless crystal with dimensions of 0.2 × 0.2 × 0.2 mm was used. C_(30)H_(50)O_3