Synthesis And Characterization Of New Phenolate-bridged Binuclear Complexes And Their Biological Activity In Cleavage Of DNA

For many years studies on synthetic compounds capable of cleaving nucleic acids and interacting with them have been one of the most vigorous fields in bioinorganic chemistry. Among these reagents, taking transition metal complexes as artificial nuclease systems formed major contents of the research. The importance of using transition metal complexes as models of natural nucleases can be summarized as the follows: First, with the knowledge obtained from the models we can learn the acting mechanisms of natural enzymes and the roles played by the metal ions in their catalytic process. Second, these cleavage reagents with high specificity and recognition can be used as tools of molecular biology in bioengineering. And third lastly, these cleavage reagents can be served as drugs in chemical therapy to treat tumors, AIDS and some genetic diseases. They can also be utilized as structural probes to study the structures of DNA and the interactions between DNA-binding protein and DNA.Based on the aforesaid two points, we chose some new systems of binuclear metal complexes with endogenous alkoxy and phenoxy bridges as our target compounds to mimic the active centers of nucleases. In the thesis, we were successful to synthesize two ligands, namely H₄L1 and H₄L2, which can supply two similar coordination environment for the two metal ions and react as ocadentate ligands with both metal ions to form structures containing N4 coordination sets and two alkoxy late and phenolate bridges. Then we investigated the interactions between the metal complexes and pBR322 DNA, CT DNA and BDNPP (bis(2,4-dinitrophenyl)phosphate), the last is a common model compound of phosphate diester. The contents of the thesis include:1. Starting from 2,6-diformyl-4-substitutedphenols and l,3-diamino-2-hydroxypropane, we have synthesized the new compounds, Zn₂L1, Zn₂L2 Mg₂L1, Mg₂L2, Fe₂L1, Mn₂L2 and Pb₂L2 with the so-called "metal ion template condensation" method and characterized their structures by infrared spectra, UV-Vis spectra, elemental analysis, molar electrolytic conductivity and mass spectrum. Meanwhile, we have got the crystal structure of two...