Molecular recognition study on supramolecular system (III) -- Chiral recognition of aromatic amino acids by binuclear Cu(II) complexes with cyclodextrins

摘要

The study of supramolecular species formed by the selective binding of substrate (guest) with a molecular receptor (host) is currently a significant topic in chemistry, biochemistry, and so on. Natural and chemically modified cyclodextrins (CDs) having fairly rigid and well-defined hydrophobic cavities can be taken as a molecular receptor to recognize a wide variety of organic, inorganic, and biological guest molecules, forming host-guest complexes or supramolecular species, which have been applied to several areas of science and technology as an excellent model system mimicking the substrate-specific interaction of enzymes. Our recent study on the molecular recognition thermodynamics of some naphthalene derivatives with natural cyclodextrins and various cyclodextrin derivatives serves our understanding of several weak forces working between receptor and substrate, including van der Waals forces, hydrogen bonding and hydrophobic interactions, giving significant results. The present study deals withthe molecular chiral recognition of aromatic amino acids by binuclear Cu(II) complexes with cyclodextrins, Such a supramolecular architecture is of special interest to us, since it occurs mostly through the weak interactions, including the rich host-guest chemistry of the cyclodextrins and the molecular chiral recognition properties. At the same time, the biological molecular chiral recognition of aromatic amino acids by binuclear copper (II)-cyclodextrins complexes is also helpful to our further understanding of the multiple recognition mechanism and the induced-fit interactive hypothesis in the process of the selective combination substrate by the biological receptor.