酯型脱氧胆酸类分子钳对芳胺及其衍生物的识别

人工受体的设计合成及其性能研究已成为生物有机化学的热点课题之一。近年来，钳形人工受体以鞭灵活的结构及易于将功能团聚集在钳形受体与底物结合的活性部位上等特点引起了人们的特别关注。胆甾不仅在生命科学、医药学等方面有着广泛的应用^1,2]，而且由于其具有刚性疏水骨架、凹形结构及价廉易得等优点，使之成为构筑钳形受体的理想单元^3-5]。我们曾报道了α-猪去氧胆酸分子钳对中性分子芳胺的识别^6]，为了进一步拓展胆甾类钳形受体在分子识别方面的应用，研究钳形受体裂穴大小、形状、微环境效应等对分子识别的影响，我们设计合成了一系列以脱氧胆酸甲酯为spacer，苯衍生物为arm的胆甾类钳形受体1-4（其结构如图1所示），利用紫外分光光度法考察了其对芳胺及其衍生物的识别性能，探讨了识别推动力。

STUDY OF RECOGNTTION OF AROMATIC AMINE BY CHIRAL MOLFCULAR TWEEZERS DERIVED FROM STEROID CHOLIC ACID

Molecular recognition properties of chiral molecular tweezers based on dexoycholic acid 1～4 for the aromatic amine have been investigated by UV-visible spectophotometric titration. The results showed that all these molecular tweezers can form 1:1 supramolecular complexes with aromatic amine. The recognizing ability of these molecular tweezers come mainly from hydrogen bonding,π-π-stacking between aromatic residues and var der Waals interaction. The size/shape-fit and geometrical complementary relationship between receptor and substrate play a crucial role in the inclusion complexation of aromatic amines with receptor 1～4.