鹅去氧胆酸分子钳对中性分子的识别性能研究  

Recognition of neutral molecules by molecular tweezers based on chenodeoxycholic acid

作　　者：赵志刚[1] 唐晓丽[1] 周彩娥[1] 

机构地区：[1]西南民族大学化学与环境保护工程学院,成都610041

出　　处：《西南民族大学学报（自然科学版）》2006年第4期681-684,共4页Journal of Southwest Minzu University(Natural Science Edition)

摘　　要：利用差紫外光谱滴定法考察了鹅去氧胆酸分子钳1～5对苯胺、对硝基苯胺、对甲氧基苯胺等中性分子的识别性能,测定了主客体间的结合常数(ka)和自由能变化(ΔG°).结果表明,主体对所考察的客体分子显示良好的识别作用,主客体间形成1∶1型超分子配合物,最大结合常数可达1292.51 L.mol-1,识别作用的主要推动力为氢键,范德华力等的协同作用.讨论了主客体间形状、大小匹配和几何互补等因素,对形成超分子配合物的影响,并利用计算机分子模拟作为辅助手段对实验结果与现象进行了解释.Molecular recognition properties of new molecular tweezers based on chenodeoxycholic acid 1~5 are investigated by using aniline,p-methoxyaniline and p-nitroaniline.The association constants(ka) and Gibbs free energy changes(ΔG°) have been determined by UV-visible spectroscopic titration for inclusion complexes of these molecular tweezers with aromatic amines in CHCl3 at 25℃.The results indicate that the supramolecular complexes formed between the hosts and guests consist of 1∶1 host and guest molecules.The greatest association constant reaches 1292.51 L.mol-1.The main driving forces come from the hydrogen bonding,π-π stacking and van der waals force in molecular recognition.The molecular recognition ability is discussed from the vewpoint of the size/shape-fit and geometrical complementary relationship between host and guest molecules.Computer-aided study is employed to elucidate the binding behavior of these molecular tweezers.

关 键 词：鹅去氧胆酸 分子钳 分子识别 紫外光谱法 分子模拟 

分 类 号：O641.3[理学—物理化学]