Dinuclear Macrocyclic Polyamine Zinc(Ⅱ) Complexes As Enzyme Models In Catalytic Cleavage Of DNA And The Modified BINOL Derivatives In Asymmetric Catalysis

Artificial enzyme is a new challenging field that is quickly developing in chemical biology. Macrocyclic polyamines metal complexes as enzyme models are widely used in chemical biology, medicine and gene therapy. In this thesis, novel macrocyclic polyamines and their zinc complexes have been designed and synthesized. Some useful results have been obtained from the study on their catalytic efficiency in DNA cleavage.A new type of dinuclear macrocyclic polyamine zinc(â…¡) complexes linked with flexible spacers has been synthesized. The structures of these novel dinuclear complexes were consistent with the date obtained from MS, ¹H NMR et al. The catalytic activity of these dinuclear complexes on the cleavage of pUC 19 supercoiled DNA was studied in detail. The results shown that the dinuclear zinc(â…¡) complexes can efficiently catalyze the cleavage of plasmid DNA (pUC 19) under physiological conditions to produce selectively nicked form (Form â…¡). Cooperative activity of the two metal centers was established by comparing the hydrolysis degree of the plasmid DNA in the reaction to the degree in the present of Zn²⁺-cyclen.Asymmetric catalysis has received considerable attention over the past few decades. C₂-symmetrical ligands possessing axial chirality have found particularly wide utility in asymmetric catalysis. BINOL and its derivatives have generated particular interest because their versatile backbone can be modified, therebyaffecting the reaction environment by influencing the properties of the metal center. In this thesis, we discussed the synthesis of two 6,6'-modified BINOL Hgands as well as their application in asymmetric phenylacetylene addition to benzaldehyde and asymmetric diethylzinc addition to benzaldehyde reactions. The results show that these ligands are not suitable for these reactions. We should have obtained some useful information for further investigation.