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首次应用变温实验方法和￣（１３）Ｃ核自旋弛豫方法研究了抗癌药β－榄香烯小分子的内部运动状况。结果表明β－榄香烯分子的六元环在所研究的温度范围（２９８～３１８Ｋ）内几乎是刚性的。该分子的整体滚动自扩散活化能为１４ｋＪ／ｍｏｌ．其六元环外侧链基团ＣＨ＿２＝ＣＣＨ＿３－和ＣＨ＿２＝ＣＨ－的整体内旋转扩散活化能均为１９ｋＪ／ｍｏｌ．而与该六元环直接相连的甲基的内旋转扩散活化能为１８ｋＪ／ｍｏｌ．这个数值大大高于连在六元环上不同位置的两个侧链基团ＣＨ＿２＝ＣＣＨ＿３一中甲基的内旋转扩散活化能（其数值分别为了７ｋＪ／ｍｏｌ和２．８ＫＪ／ｍｏｌ）．３个不同位置的甲基的内旋转扩散活化能有很大差别可能是由它们所处的分子空间环境不同而引起的。
The first time the variable temperature experimental method and ~ (13) C nuclear spin relaxation method were used to study the internal movement of anticancer drug β-elemene small molecule. The results show that the six-membered ring of β-elemene molecules is almost rigid within the investigated temperature range (298-318K). The molecular overall rolling self-diffusion activation energy of 14kJ / mol. The six-membered ring outer side chain groups CH_2 = CCH_3- and CH_2 = CH- in the overall rotational diffusion activation energy are 19kJ / mol. The activation energy of the internal rotation diffusion of the methyl group directly connected to the six-membered ring is 18 kJ / mol. This value is much higher than the inner rotational diffusion activation energy of the methyl group of CH_2 = CCH_3, which is two side chain groups attached to the six-membered ring at different positions (the values are 7 kJ / mol and 2.8 kJ / mol, respectively). The three different positions of methyl rotary diffusion activation energy can be very different from the molecular environment in which they are caused by different environments.