Preparation Of Protopanaxadiol Type Ginsenosides 20（R）-Rg₃

Ginsenoside Rgs, as an important physiological activity ingredients in ginseng, which plays an important role in anti-tumor, belongs to protopanaxadiol type saponin. In this paper, to obtain the ginaenoside 20(R)-Rg), the isomer of ginsenoside Rg3 was produced from protopanaxadiol type (PPD) ginsenoside, and the isomer of Rg3 was separated to obtain single ginsenoside Rg3 isomer.50g PPD was transformed to the complex consisted of isomers of ginsenoside Rg3. In the complex consisted of isomers of ginsenoside Rg3, based on the different solubility,7.33g 20(R)-Rg3 with the purity of 64.0% was obtained firstly. And then the mixture of 20(S)-Rg3, Rgs and Rk1 were separated by silica gel column.10.77g 20(S)-Rg3 and 6.98g Rg5(Rk1) were obtained, which were both single point on TLC.20(S)-Rg3,20(R)-Rg3 were purified by crystallization.3g 20(S)-Rg3 and 3g 20(R)-Rg3 were crystallized respectively,which obtainl.98g 20(R)-Rg3 with the purity of 94.58%, and 1.02g 20(S)-Rg3 with the purity above 98%.