Nakamura Takashi, Kaneko Yuya, Nishibori Eiji, Nabeshima Tatsuya
Graduate School of Pure and Applied Sciences and Tsukuba Research Center for Interdisciplinary Materials Science (TIMS), University of Tsukuba, 1-1-1 Tennodai, Ibaraki, Tsukuba, 305-8571, Japan.
Nat Commun. 2017 Jul 25;8(1):129. doi: 10.1038/s41467-017-00076-8.
Most biological and synthetic receptors for small organic molecules employ a combination of relatively weak intermolecular interactions such as hydrogen bonds. A host compound that utilizes stronger yet reversible bonding in a synergistic manner could realize precise recognition, but the regulation and spatial arrangement of such reactive interaction moieties have been a challenge. Here, we show a multinuclear zinc complex synthesized from a macrocyclic ligand hexapap, which inwardly arranges labile metal coordination sites for external molecules. The metallomacrocycle forms a unique wavy-stacked structure upon binding a suitable length of dicarboxylic acids via multipoint coordination bonding. The saddle-shaped deformation and dimerization realize the differentiation of the interaction moieties, and change of guest-binding modes at specific metal coordination sites among the many present have been achieved utilizing acid/base as external stimuli.Synergistic use of coordination bonds that are strong and reversible realizes unique molecular recognition in artificial systems. Here, the authors show that a zinc-based metallomacrocyle can bind dicarboxylic acids of suitable length at specific metal sites by shape deformation and dimerization.
大多数用于小分子有机化合物的生物和合成受体采用相对较弱的分子间相互作用（如氢键）的组合。一种以协同方式利用更强但可逆键合的主体化合物可以实现精确识别，但此类反应性相互作用部分的调控和空间排列一直是一个挑战。在此，我们展示了一种由大环配体六聚体合成的多核锌配合物，它为外部分子向内排列不稳定的金属配位位点。该金属大环化合物通过多点配位键结合合适长度的二羧酸后形成独特的波浪状堆积结构。鞍形变形和二聚化实现了相互作用部分的区分，并且利用酸/碱作为外部刺激，在众多存在的特定金属配位位点实现了客体结合模式的改变。对强且可逆的配位键的协同利用在人工体系中实现了独特的分子识别。在此，作者表明基于锌的金属大环化合物可以通过形状变形和二聚化在特定金属位点结合合适长度的二羧酸。
