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Objective To explore an efficient preparation method of pseudo-ginsenoside Rg2, pseudo-ginsenoside Rh1, and pseudo-PPT, as to provide theoretical basis for the preparation of pseudo-ginsenosides and pseudo-PPT. Methods Ginsenosides Re, Rh1, and PPT as raw material, via a simple three-step called acetylation, elimination-addition and saponification achieve the preparation of 20 (E/Z)-pseudo-ginsenoside Rg2, 20 (E/Z)-pseudo-ginsenoside Rh1, and 20 (E/Z)-pseudo-PPT. The detailed structure elucidation of the compounds were obtained by NMR, HR-ESI-MS, and IR. Results The production rates of 20 (E/Z)-pseudo-ginsenoside Rg2, 20 (E/Z)-pseudo-ginsenoside Rh1, and 20 (E/Z)-pseudo-PPT were 41%/13%, 43%/11%, and 56%/15%, respectively. Among them, 20 (Z)-pseudo-PPT was identified as new triterpenoid. Conclusion The method through the price relatively cheap and easy gain reactants ginsenoside Re, ginsenoside Rh1, and PPT prepared active better pseudo-ginsenoside Rg2, pseudo-ginsenoside Rh1, and pseudo-PPT, the method for the preparation of other types of pseudo-ginsenoside provides a new train of thought. At the same time, the method is simple and the yield is high.
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A novel organic-inorganic layered titanosilicate consisting of Ti-containing MWW-type nanosheets and piperidine ligands was constructed. It exhibited an unprecedented high catalytic activity and recyclability in alkene epoxidation.
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0.05).The effective rate on relieving traditional Chinese medical syndrome was 95.0% in the treatment group and 73.3% in the control group,the difference being significant(P0.05).After treatment,the parameters of 24-h dynamic blood pressure were improved in both groups(P
