人参皂甙Re结构与振动光谱的密度泛函理论研究  

Structure and Vibrational Spectroscopy of Ginsenoside Re:Density Functional Theory Study

作　　者：尚小红[1] 惠歌[1] 赵雨[2] 王旭[1] 赵大庆[2] 吴凤清[3] 赵冰[1] 

机构地区：[1]吉林大学超分子结构与材料国家重点实验室,吉林长春130012 [2]长春中医药大学新药研发中心,吉林长春130117 [3]吉林大学化学学院,吉林长春130021

出　　处：《光谱学与光谱分析》2009年第10期2765-2768,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(20573041);吉林省科技厅重点项目(20060902-02;20075020)资助

摘　　要：利用密度泛函理论方法(B3LYP/6-31G)对人参中的有效成分人参皂甙Re(Ginsenoside Re)的两种异构体20-(R)-Re和20-(S)-Re的平衡几何构型进行了优化,对其振动频率进行了计算,二者的空间结构有明显的不同,振动光谱也有一定的区别。这些变化是因为20号手性碳4个取代基空间取向不同导致两种异构体的堆积方式不同,从而导致红外和拉曼光谱峰位以及峰形变化。根据理论上计算出来的红外强度与拉曼活性及相对应的频率,对实验得到的红外光谱和拉曼光谱进行了指认,发现计算值1541,1456和1424cm-1等谱峰,可作为区分两种异构体的特征谱峰。计算的振动频率同拉曼光谱的实验结果较好吻合。这一结果表明,振动光谱可以用来对人参有效成分进行鉴定。Density functional theory was used to optimize the geometry structure of two isomers of ginsenoside, Re, 20-（R）-R and 20-（S）-Re. The ginsenoside Re is an active constituent in ginseng. The calculated results show that there is an obvious difference in space structure between 20-（R）-R and 20-（S）-Re. The main reason for that can be the difference in the space orientation of the four constituents in the 20th carbon （chiral）, which leads to the different stacking mode and causes the difference in vibrational spectra in the two isomers. The experimental IR and Raman spectra were assigned according to the calculated frequency, theoretical IR intensity and Raman active. The calculated vibrational peaks at 1 541, 1 456 and 1 424 cm^-1 can be used to distinguish the two isomers. The result shows a good agreement between the calculated and the experimental Raman spectra. The vibrational spectra can be used to identify the active constituent in ginseng.

关 键 词：人参皂甙 Re 振动光谱 密度泛函 DFT 

分 类 号：O657.3[理学—分析化学]