Studies on saponin from seeds of Trigonella foenum-graecum (Ⅰ) Isolation and structural elucidation for a new saponin A and its secondary glucosides / 中草药

ABSTRACT

Object To investigate the saponin from the seeds of Trigonella foenum graecum Linn (STFG) Methods The total saponin from STFG was extracted and purified by using the absorptive resin, the single saponin was isolated by using the column chromatography as well as dry column chromatography of silica gel H The chemical structure was elucidated by 13 CNMR , FAB MS, DEPT spectroscopic evidence and the results of fraction hydrolysis of acquiring their secondary glucosides Results A new saponin A from the total saponin has been obtained, the fraction hydrolysis carried out and the secondary glucoside Ⅰ and Ⅱ identified by determining the structure of saponin A The chemical structure of saponin A is diosgenin 3 O ? L rhamnopyranosyl(1→4) ? D glucopyranosyl(1→4) ? D glucopyranoside The secondary glucoside Ⅰ is diosgenin 3 O ? D glucopyranoside; Ⅱ is diosgenin 3 O ? D glucopyranosyl(1→4) ? D glucopyranoside Conclusion Glucoside A is a new saponin with three molecules of sugar