Approach toward Artificial Enzyme Models Using Water-soluble Cyclophanes with Hyrophobic Cavities

使用具有疏水空腔的水溶性环芳的人工酶模型的方法

基本信息

批准号：
05557096
负责人：
KOGA Kenji
金额：
$ 3.9万
依托单位：
University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

项目摘要

Studies aiming at application of cyclophanes having diphenylmethane units to artificial enzyme models in aqueous solutions and at membrane surfaces were carried out, and the following results were obtained.1. Catalytic cyclophanes in which an imidazolyl or thiol group as a catalytic functional group was introduced to a cyclophane macrocycle having diphenylmethane units were synthesized, and their abilities to accelerate ester docomposition were compared in aqueous solution (pH 8.65). Although 3.8-fold acceleration was observed for a cyclophane having an imidazolyl group, control experiments with addition of a nonreactive guest or 4-methyl-imidazole without a cyclophane ring showed that the acceleration by the imidazolyl cyclophane was not due to the reaction with a guest included in the cyclophane cavity. These results manifested the necessity of the design of catalytic cylophanes in which the catalytic group is located in close proximity to the reactive site of the included guest.2. An optically active, anionic cyclophane having a C_2-symmetrical structure with two OH groups was synthesized as a new type of chiral hydrophobic cavity that is capable of introducing catalytic functional groups. This cyclophane showed strong complexation to cationic aromatic guests (K_3-10^3M^<-1>) in aqueous solution (pD12.8).3. A series of lipophilic cyclophanes having long alkyl chains were synthesized to achieve molecular recognition at a membrane surface, evaluated as guest-induced changes in membrane potential by using PVC-supported liquid membrane systems. A cyclophane having a definite charged group on one side and a lipophilic alkyl chain on the other side of the benzene rings gave greatest potential changes, indicating an important principle for designing interfacial receptors.

针对含有二苯甲烷单元的环烷在水溶液中和膜表面的人工酶模型中的应用进行了研究，得到了以下结果： 1．合成了将咪唑基或硫醇基作为催化官能团引入到具有二苯基甲烷单元的环烷大环中的催化环烷，并比较了它们在水溶液（pH 8.65）中加速酯合成的能力。尽管观察到具有咪唑基的环烷有 3.8 倍的加速，但添加非反应性客体或不带环芳环的 4-甲基咪唑的对照实验表明，咪唑基环烷的加速不是由于与客体的反应所致。包含在环芳空腔中。这些结果表明了设计催化基团靠近客体反应位点的催化环芳烷的必要性。 2．合成了具有两个OH基团的C_2对称结构的光学活性阴离子环烷作为能够引入催化官能团的新型手性疏水空腔。该环烷在水溶液中与阳离子芳香族客体(K_3-10^3M^<-1>)表现出强烈的络合作用(pD12.8)。3。合成了一系列具有长烷基链的亲脂性环烷，以在膜表面实现分子识别，并通过使用 PVC 支撑的液膜系统评估客体诱导的膜电位变化。苯环一侧具有明确的带电基团，另一侧具有亲脂性烷基链的环烷具有最大的潜在变化，这表明了设计界面受体的重要原则。