<i>J</i>-Based Analysis and DFT-NMR Assignments of Natural Complex Molecules: Application to 3β,7-Dihydroxy-5,6-epoxycholestanes
作者:Jesús Javier Poza、Carlos Jiménez、Jaime Rodríguez
DOI:10.1002/ejoc.200800358
日期:2008.8
four 3β,7-hydroxy-5,6-epoxycholestanes were easily prepared from cholesterol, and their NMR spectroscopic data were experimentally obtained from 1D and 2D NMR experiments. An exhaustive QM-J-based analysis was then performed to replicate the experimental H–H and C–H coupling constants as well as the 13C NMR chemical shifts. The B3LYP GIAO methodology with the 6-311-G(d,p) basis set was chosen and showed
为了重现环氧和羟基官能团的立体化学配置,从胆固醇中很容易制备了四种 3β,7-羟基-5,6-环氧胆甾烷,它们的核磁共振光谱数据是从一维和二维核磁共振实验中获得的。然后进行基于 QM-J 的详尽分析以复制实验 H-H 和 C-H 耦合常数以及 13C NMR 化学位移。选择了具有 6-311-G(d,p) 基组的 B3LYP GIAO 方法,并表明从环 A 和 B 获得的数据足以计算 5,6-环氧基和 7-羟基的正确立体化学. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)