基于自主研发的500 MHz NMR谱仪的紫杉醇结构解析

中国科学院武汉物理与数学研究所(WIPM)于2010年成功研制了500 MHz(WIPM-I 500)高分辨超导核磁共振(NMR)谱仪,并将其投入实际应用中.然而,关于其二维核磁共振(2D NMR)谱图的准确性及在此基础上对复杂物质的结构解析尚无系统完整的数据报道.该文利用WIPM-I 500型NMR谱仪,对紫杉醇样品进行了1D NMR及2D NMR(包括~1H-~1H COSY、~1H-~1H TOCSY、J-Res、~1H-~(13)C HMQC和~1H-~(13)C HMBC)实验,将谱图分析结果与进口仪器进行了对比.结果表明:利用WIPM-I 500型NMR谱仪能够采集准确的2D NMR谱图,为紫杉醇的正确归属提供了实验基础;而且该文也纠正了文献中对紫杉醇的错误归属.

Structure Elucidation of Taxol Based on Two-Dimensional NMR Spectra Collected on a 500 MHz NMR Spectrometer Built In-House

A 500 MHz NMR spectrometer was successfully built in-house in Wuhan Institute of Physics and Mathematics in 2006, and it had been used for researches in many areas. However, the performance of this spectrometer in acquiring two-dimensional (2D) NMR spectra needed for structure elucidation had not been evaluated until now. In this paper, we acquired all the one-dimensional (1D) and 2D (i.e., 1H-1H COSY, 1H-1H TOCSY, J-Res, 1H-13C HMQC and 1H-13C HMBC) NMR spectra of taxol on this spectrometer, and used these spectra to elucidate the structure of the compound. The results showed that, with the spectra acquired on the 500 MHz NMR spectrometer built in-house, the structure of taxol could be elucidated correctly. We also corrected some incorrect NMR assignments of taxol existing in the literature.