一种百合甾体皂苷纯度及糖链结构核磁共振法分析

采用多种NMR分析技术,首次对百合甾体皂苷(25R,26R)-26-甲氧基螺甾烷-5-烯-3β-α-L-鼠李糖-(1→2)-[β-D-葡萄糖-(1→6)]-β-D-葡萄糖苷的1H和13C NMR信号进行了全归属,特别是应用选择性的1D TOCSY和1D NOESY核磁共振分析技术,对该化合物1中的氢谱信号严重重叠的糖链进行了详细的分析,提出了一套对甾体皂苷糖链信号进行全归属的核磁共振法.在确认其结构的基础上,建立了核磁共振法(1H NMR)测定该化合物1的纯度,给出了完整的实验条件,线性回归系数为0.9998,重复性实验RSD为0.58％,稳定性实验RSD为0.24％,操作简单、快速准确,且不需要其它对照品,是中药化学对照品纯度研究的一个有益补充.

Determination and Structural Analysis of Sugar Moieties of Lily Steroidal Saponin by NMR

The molecular structure of(25R,26R)-26-methoxyspirostan-5-ene-3-β-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopy ranosyl-(1→6)]-β-D-glucopyranoside,was elucidated by 1D NMR and 2D NMR for the first time,and its complete assignment of 1H and 13C NMR chemical shifts were also obtained.In particular,the analytical method of combining 1D TOCSY and 1D NOESY was applied to analyze overlapped 1H NMR signal of the sugar in detail,and a way to assign NMR signal of the sugar of steroidal saponin completely was established.Meantime,the quantitative determination of the above compound by 1H NMR has been developed in this paper.The optimum experimental conditions has been described.The linear regression coefficient was 0.9998,and RSD was 0.58%,its efficacy has been proved through the experiments of repeatability and linearity.This method is simple,reliable and accurate,and without reference compound.The data obtained could be very important for structure identification and structure-activity relationship research.