2D-NMR测定人参皂苷Rb_1溶液中的三维空间结构

Determination of Three Dimensional Structure of Ginsenoside Rb_1 in Solution by Two Dimensional Magnetic Resonance Spectroscopy

本文用一维和二维NMR归属了人参皂苷Rb_1的质子化学位移,测定了质子偶合常数,并用相敏NOESY谱测定了分子中质子间的距离.以所测定的化学位移,偶合常数和质子间距等NMR结构参数为初始数据,用自编和改进的分子结构计算程序计算出人参皂苷Rb_1在溶液中的三维空间结构.

In tnis paper, the chemical shifts of ginsenoside-Rb1 were completely assigned by homonuclear correlation spectroscopy, single and double homonuclear RELAY spectroscopy, and the coupling constants were measured by 2D J-resolved spectroscopy and 1D resolution-enhanced spectrum. The inter-proton distances were calculated by phase sensitive NOESY spectrum acoording to 1/γij-6∝Aij(Aij was the integration value of cross peaks in phase sensitive NOESY spectrum), Using the structural parameters measured by NMR methods as initial input data, the three dimensional structure of ginsenoside-Rb1 in solution was calculated by combination of WUPH method with molecular mechanics.