The Studies Of Coordination Behavior Of Fourth Period Trace Elements With Biological Ligands

The phase equilibrium properties of ternary systems Cr(NO3)3-His/Met-H2O and CrCl3-His-H2O have been studied at 25℃. The experimental results indicate that eight congruty soluble complexes exist in these systems. These eight complexes have been prepared in water. Eighteen other complexes of different amino acids with transitional element compounds with mole rate of 1:2 have been synthesized in combination solvents. The ingredients of these complexes have been determined through chemical and elemental analysis. The infrared spectroscopic analysis reveal that for the complexes of chromiunm nitrate with metheionine, amino, carboxy and sulfur have all contributed to the coordination effects. Apart from chromium, for the complexs of transitionnal elements with histidine, amino, carboxy and imdazalyl have all participated to coordination beheavior. And for the other complexes, only amino and carboxy have taken part in the coordination effects. X-ray fluoresence analysis show that all the complexes are non-crystaline state. The fluorescence analysis express some changes between the complexes and the amino acids. They all indicate the coordination effects. Thermal analysis results indicate that most of the complexes are decomposition through losting water and part of the amino acid at the same time.The solution enthalpy studies of His, Met, Phe and their complexes with zinc indicate that amino acids and complexes with 1:3 mole rate are endothermic, the complexes with 1:1 and 1:2 mole rate are exothermic. The standard formation enthalpies of aqueous amino acids have been calculated. The thermal effects of the complexes are different in stomach solution from in water at 25℃. The solid-solution reaction thermodynamics of histidine with zinc have been investigated. The tesults show that the complexes could be synthesized under moderate condition. The solution-solution reaction thermodynamics of chromium coloride, sulfate and nitrate with histidine have been studied. The rate constant, reaction order, activation energy, pre-exponential constant, activation free energy, activation enthalpy and active entropy of different reactions have been calculated. The reaction of manganese coloride with histidine is endothermic and the reaction order is 0.5. While the other coloride reactions are exothermic and they are all order one reaction. As the timpeature rised, the thermal effects have increased. Allthese reactions are easily taken place. The thermodynamics studies of taurine with zinc coloride indicate the reaction order is one and the reaction is also easily happened.The complexes of zinc with S2N2 coordinated atoms have been designed and synthesed. The propertses of these complexes have been studied. The alkylating reactions of these complexes have been studied with NMR.