疎水性内孔を有する水溶性シクロファン類の設計, 合成, 及びその分子認識機能
1988 年 108 巻 2 号 p. 91-108
詳細
1988 年 108 巻 2 号 p. 91-108
Water-soluble cyclophanes constitute a promising group of totally artificial hosts having hydrophobic cavities to capture organic guests in water. A series of novel water-soluble cyclophanes, Cpnn (4, 14) and QCPnn (34), were designed and synthesized with two diphenylmethane skeletons as structural units for well-defined hydrophobic cavities. An X-ray crystallographic study on the host-guest complexes proved the formation of inclusion complexes of well-defined structure; this is the first direct evidence of inclusion complex formation by a water-soluble cyclophane. The formation of well-defined inclusion complexes in water was also confirmed by a detailed proton nuclear magnetic resonance study. The complex formation in water was found to occur with remarkable selectivity towards aromatic guests. This aromatic selectivity was reasonably attributed to the formation of well-defined hydrophobic cavities fitting well with the aromatic rings of the guests. The above findings on the molecular recognition function of CPnn and QCPnn led to rational design and syntheses of host molecules aiming at inclusion of bulky aliphatic guests (51, 52), as well as at chiral recognition (55, 56) and dual binding (60) of aromatic guests.
