目的：通过理论计算比较五味子中4种木脂素的结构和谱学性质差异。方法：采用密度泛函理论（DFT）B3LYP方法和极化连续模型（PCM），在6-31+G**水平上对气相和甲醇溶剂中的4种木脂素进行理论计算，对它们的分子几何构型、紫外-可见光谱、红外振动光谱和电子结构进行了分析。结果：4种木脂素的几何结构参数在气相和甲醇中计算值相差不大，紫外-可见光谱特征峰除酯甲较高外，其余三者非常接近；红外特征峰彼此相近，在甲醇中峰强度增加，红外光谱与官能团大致符合；4种木脂素都是极性分子，前线轨道分布基本类似，但酯甲最低未占轨道（LUMO）则是由苯甲酰基构成；计算数值与实验值较为符合。结论：通过理论计算值与实验值进行对比分析，用量子化学方法对五味子木脂素类化合物进行理论研究是有效的，并能通过计算来讨论其电荷转移和取代基效应，对理论研究和实验研究具有一定的参考价值。%Objective: To analyze the structures and spectral difference of four kinds of lignans in Schisan-dra Chinensis (Turcz.) Baill. through theoretical calculation.Methods: The geometrical structure, ultraviolet-visible spectrum, infrared vibrational spectrum and electronic structure of four kinds of lignans in Schisandra Chinensis were studied at the level of DFT/B3LYP/6-31+G** in gas phase and methanol, the solvent effects were considered by polarizable continuum model (PCM).Results: The optimized geometrical structure parameters of the lignans were close to each other in gas phase and in methanol. The calculated UV-Vis spectral characteristic peaks were similar to each other but Schisantherin A was higher than the other three. To the IR vibrational spec-tra, the peak strength increased in methanol. All lignans were polar molecules, and only the LUMO of Schisan-therin A located at benzoyl group. All computed data were agreed well with available reported data.Conclusion:The results of deep understanding of the structure and properties of four kinds of lignans in Schisandra Chinensis (Turcz.) Baill. have certain scientiifc signiifcance.
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