人参皂苷Rh2的C-20构型确证

目的确证人参次苷H主成分人参皂苷Rh2的结构与空间构型。方法单晶X-射线衍射，HPLC、13C—NMR比较与其C-20的R型异构体的差异。结果HPLC保留时间显示人参皂苷H中主成分人参皂苷Rh2与酸降解尺型异构体不同，二者是两种不同成分；13C-NMR数据与文献报道的20（S）-人参皂苷Rh2一致。单晶X-射线衍射结构分析也证实其为20（S）人参皂苷Rh：。结论人参次苷H主成分为20（S）-人参皂苷Rh2。

Determination of C-20 steric configuration for ginsenoside Rh2

Objective To confirm the structure and steric configuration of the main component of secondary-ginsenoside-H, 20（S）-ginsenoside Rh2. Methods Through the single crystal X-ray diffraction analysis, HPLC, and 13C-NMR data analysis compared with R-type epimer after acid degradation treatment. Results The retention time of HPLC show the main component of secondary-ginsenoside-H, ginsenoside-Rh2, and the ginsenoside Rh2 from PQS （Panax quinquefolium saponins from stems and leaves） after acid degradation treatment to be two different epimers. 13C-NMR spectroscopic data showed the ginsenoside Rh2 separated from secondary-ginsenoside-H has the same data with reported in literatures. And the single crystal X-ray diffraction analysis of chemical structure also prove to be 20 （S）-ginsenoside Rh2. Conclusion The C-20 of ginsenoside Rh2 epimer, a main component of secondary-ginsenoside H, is S-type.