Supramolecular Chemistry Composed of Porphyrins and Cyclodextrins

卟啉和环糊精组成的超分子化学

基本信息

批准号：
14340224
负责人：
KANO Koji
金额：
$ 9.66万
依托单位：
DOSHISHA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

项目摘要

1) Porphyrin Permethylated Cyclodextrin Complexes : We found that some water-soluble tetraarylporphyrins form extremely stable 1:2 inclusion complexes with per-O-methylated β-cyclodextrin (TMe-β-CD). The complexes were formed quantitatively in aqueous solutions even when the concentrations of both host and guest were 10-6 M. The results strongly suggest the possibility of this system to be utilized for preparing various supramolecular systems2) Mechanism for Formation of Porphyrin-TMe-β-CD Complexes : Mechanism for formation of extremely stable porphyrin-TMe-β-CD complexes was studied. As a result, it was clarified that TMe-β-CD can alter its shape according to the shape of a guest resulting in "induced-fit type complexation" as is found in biological systems. The optimum van der Waals contacts between the host and the guest are achieved by the induced-fit type inclusion.3) Formation of Heteroporphyrin Arrays : A very convenient method to prepare heteroporphyrin arrays was developed by … More applying the results on complexation of water-soluble porphyrins and TMe-β-CD. A scaffold is the tetraphenylporphyrin whose para-positions of the peripheral phenyl groups are attached by per-O-methylated β-cyclodextrin moieties. Such a porphyrin-cyclodextrin conjugate can form heteroporphyrin array just by mixing with another porphyrin solution. Very efficient energy transfer from zinc complex of water-soluble anionic porphyrin (ZnTPPS) to the free base porphyrin of the conjugate was achieved just by mixing the solution of the conjugate with that of ZnTPPS.4) Met-Myogbbin Model : Fe(III) complex of the anionic porphyrin (Fe(III)TPPS) forms a very stable 1:2 inclusion complex with TMe-β-CD. Such a complex can act as a met-myoglobin model whose Fe(III) center is bound to various anions in aqueous media. The fact that no anion binding to Fe(III)TPPS occurs in aqueous solution in the absence of TMe-β-CD, TMe-β-CD seems to show the function similar to proteins in biological system. High selectivity was found in anion binding to Fe(III)TPPS/FMe-β-CD complex; namely N3- is selectively bound to the complex. Hydrophilicity, basicity, and shape of an anion are the factors to determine the stability of the anion-bound Fe(III)TPPS/TMe-β-CD complex.5) Myogbbin Model and Reversible O2 Binding : A met-myoglobin model was constructed by Fe(III)TPPS and a per-O-methylated β-cyclodextrin dimer where two cyclodextrin moieties were linked with a bridge containing a pyridine moiety as a proximal base. We call such a model "met-hemoCD". Met-hemoCD was reduced by dithionite to form hemoCD (Fe(II)TPPS/cyclodextrin dimer), which bound dioxygen reversibly. The half life time of oxy-hemoCD was 30h in pH 6.0 phosphate buffer. The dioxygen affinity was determined to be 17 Torr. HemoCD shows the functions similar to myoglobin. The present system is the first example of the model of myoglobin or hemoglobin that works in aqueous solution. Less

1) 卟啉全甲基化环糊精复合物：我们发现一些水溶性四芳基卟啉与全O-甲基化β-环糊精(TMe-β-CD)形成极其稳定的1:2包合物，即使在水溶液中也能定量形成该复合物。主体和客体的浓度均为10-6 M。结果强烈表明该系统可用于制备各种超分子系统2)卟啉-TMe-β-CD复合物的形成机制：研究了极其稳定的卟啉-TMe-β-CD复合物的形成机制，结果表明TMe-β-CD可以根据形状改变其形状。客体的形状导致“诱导配合型络合”，如在生物系统中发现的那样。主体和客体之间的最佳范德华接触是通过诱导配合型包含物实现的。3) 的形成。异卟啉阵列：应用水溶性卟啉和 TMe-β-CD 络合的结果开发了一种非常方便的制备异卟啉阵列的方法。支架是四苯基卟啉，其外围苯基的对位通过这种全O-甲基化β-环糊精部分只需与另一种卟啉-环糊精缀合物混合即可形成杂卟啉阵列。只需将缀合物溶液与 ZnTPPS 溶液混合即可实现从水溶性阴离子卟啉 (ZnTPPS) 的锌络合物到缀合物的游离碱卟啉的非常能量转移。4) Met-Myogbbin 模型：Fe (III)阴离子卟啉络合物(Fe(III)TPPS)与TMe-β-CD形成非常稳定的1:2包合物，这样的络合物可以起作用。作为铁肌红蛋白模型，其 Fe(III) 中心与水介质中的各种阴离子结合。事实是，在不存在 TMe-β-CD、TMe-β 的情况下，水溶液中不会出现与 Fe(III)TPPS 结合的阴离子。 -CD似乎显示出与生物系统中的蛋白质相似的功能，阴离子与Fe(III)TPPS/FMe-β-CD复合物结合，即N3-选择性地与复合物结合。阴离子的碱度和形状是决定阴离子结合的 Fe(III)TPPS/TMe-β-CD 复合物稳定性的因素。5) Myogbbin 模型和可逆 O2 结合：Fe 构建了met-肌红蛋白模型(III)TPPS和全O-甲基化β-环糊精二聚体，其中两个环糊精部分与含有吡啶部分作为近端碱基的桥连接。这种模型“met-hemoCD”被连二亚硫酸盐还原形成hemoCD（Fe(II)TPPS/环糊精二聚体），其可逆地结合双氧。oxy-hemoCD在pH 6.0磷酸盐缓冲液中的半衰期为30小时。确定的双氧亲和力为 17 Torr，显示出与肌红蛋白相似的功能。在水溶液中起作用的肌红蛋白或血红蛋白较少。