Pairs Of Salicylaldehyde Diethylene Amine Manganese Complexes Active Theoretical Research

Superoxide dismutase(SOD) has very important purposes in chemistry,biology and medical science,but lower stability,macro molecular weight,lower penetrability,short life and immunogenic property that restrict the application of natural Superoxide Dismutase(SOD),As a conquence,studies on low molecular weight SOD mimics have always been a hotspot.SOD simulation of the chemical understanding of the natural enzyme has become a powerful tool to replace the natural SOD clinical application, showing good prospects.The QSAR model of the bis(salicylaldehyde) ethylenediamino manganese derivatives is established by quantum chemistry,molecular mechanics,statistical analysis methods.The structure and activity relationship is discussed from the electronic structure of these compounds.This work can provide theoretical guidance to predict the activity and design such compounds.The main content of this article:In the first chapter we summarize the background and significance of the issue.In the second chapter we introduce the development of computer chemistry and the research actuality of QSAR(Quantitative Structure-Activity Relationships),the calculation methods and theories of the quantum chemistry are also introduced.The research of this issue is divided into two parts:The first part(the third chapter): The electronic and geometric structures of two kinds of salicylaldehyde diamine manganese complexes has been systemically studied,by using the Density Functional Theory(DFT) method at B3LYP/Lanl2DZ level.Solvent effects of two manganese complexes have been investigated based on Onsager self-consistent reaction field (SCRF) model in different solvent.The calculation results show that:solvent effects have no effect on the order of electronic configuration energy of the system,the calculation to atomic charge has hardly any affect nearly after considering the condition of solvent.With the polarity of the solvent strengthening,the system tends to steady, and the discrepancy of the gap of frontier orbital energy becomes small. The second part(the fourth chapter):The quantitative structure-activity relationship(QSAR) of bis(salicylaldehyde)ethylenediamino manganese derivatives is systematically studied by using the density functional theory(DFT),molecular mechanism(MM+)and regression analysis methods.Via a stepwise regression analysis, some main independent factors which affect the activity of the compounds is selected out,and then the QSAR equation is established.It has been found that the gap of frontier orbital energy(△ξ_L-H) of the compound,the molecule polarizability(a),as well as the total net charge of benzene-ring(ΣQ_A) are the main independent factors contributing to the bioactivity QSAR equation of the model:pIC₅₀=13.818-68.965×△ξ_L-H -0.097×ΣQ_A -0.001×a R²=0.935 SE=0.06136 F=47.807 n=14There is some predictive capability for the bioactivity of bis(salicylaldehyde) ethylenediamino manganese complexes derivatives according to QSAR equation. When designing such compounds,it is necessary to get better biological activity of compounds by choosing the right size substituents,number of substituents and reducing the charge on benzene ring.