Construction of Tailormade Sugar Host Molecules Bearing High Polymer Recognition Ability

在生物系统中，生物聚合物如核酸和抗体有效地作为宿主分子来精确识别特定的客体聚合物。对聚合物客体具有如此精确识别能力的人工宿主聚合物的开发具有重要意义，因为这些宿主聚合物可用于构建新型识别装置。在这项研究中，我们研究了三种宿主分子，骨架修饰环糊精（CD）衍生物，部分2,3- o甲基化直链淀粉和γ-环糊精（γ-CD）与各种聚合物的包合形成，以开发能够选择性与特定聚合物络合的宿主分子。骨架修饰的CD衍生物具有β-(1,4)糖苷键，不仅能与聚四氢呋喃（PTHF）和聚ε-己内酯（PCL）等传统聚合物客体形成包合物，还能与聚丙烯酸PAA形成包合物，生成新型伪聚己烷。这是CD-PAA包合物的第一个例子。骨架修饰的CD衍生物可以有效地与主链上有取代基的聚合物客体形成包合物，而不是与线性聚合物形成包合物。部分2,3- o甲基化的直链淀粉与PTHF和PCL在DMSO-H_2O（1:9）溶液中简单混合即可形成包合物。直链淀粉甲基化程度影响其对PTHF和PCL的包合能力：甲基化程度为8%和20%的MAs与这些客体聚合物形成包合物，而甲基化程度超过33%的MAs与客体聚合物形成的包合物很少。γ-CD与等规聚甲基丙烯酸甲酯（it-PMMA）形成包合物比与异规聚甲基丙烯酸甲酯（st-PMMA）形成包合物更有效。γ-CD与st-PMMA之间包合物的形成受γ-CD添加量的强烈影响，γ-CD_st-PMMA包合物的形成需要添加过量的γ-CD。少

In biological systems, biopolymers such as nucleic acids and antibodies effectively function as host molecules to precisely recognize particular guest polymers. The development of artificial host polymers possessing such precise recognition ability towards polymeric guests is of great importance, since these host polymers can be useful for the construction of novel recognition devices. In this study, we examined the inclusion complex formation of three kinds of host molecules, a skeleton-modified cyclodextrin (CD) derivative, partially 2,3-O-methylated amyloses, and γ-cyclodextrin (γ-CD), with various kinds of polymers in order to develop a host molecule capable of selectively complexing with a specific polymer.The skeleton-modified CD derivative, which bears a β-(1,4) glucosidic bond, formed an inclusion complex with not only conventional polymeric guests such as polytetrahydrofuran (PTHF) and poly(ε-caprolactone) (PCL), but also with poly(acrylic acid) PAA to generate novel pseudo-po … More lyrotaxanes. This is the first example of a CD-PAA inclusion complex.The skeleton-modified CD derivative was found to effectively form inclusion complexes with polymeric guests with substituents on the main chain rather than with the linear polymer.Partially 2,3-O-methylated amyloses efficiently formed inclusion complexes with PTHF and PCL by simply mixing them in DMSO-H_2O (1:9) solution. The degree of methylation of amylose affected the inclusion ability towards PTHF and PCL: MAs with 8 and 20% methylation formed inclusion complexes with these guest polymers, while MAs with more than 33% methylation formed few inclusion complexes with the guest polymers.γ-CD was found to form inclusion complexes with isotactic poly(methyl methacrylate) (it-PMMA) more effectively than with syndiotactic poly(methyl methacrylate) (st-PMMA). The formation of an inclusion complex between γ-CD and st-PMMA was strongly influenced by the amount of γ-CD added, and the addition of an excess amount of γ-CD was required for γ-CD_st-PMMA complex formation. Less