Theoretical studies on the effects of Cu(II) on glycylglycine

B3LYP/6-31++G** method has been applied to study the effects of Cu(Ⅱ) on glycylglycine.16 stable complexes have been found.The coordination type,the relative activity of the coordination atoms and the influence of Cu(Ⅱ) on the glycylglycine properties have been discussed.The results have been found as follows:The interaction between glycylglycine and Cu(Ⅱ) is very strong so the binding energy reaches-1 154.45 kJ/mol;The most stable complex of glycylglcine-Cu(Ⅱ) is a tridentate structure,the coordination atoms are two nitrogen and the carboxyl oxygen,the coordination type is square planar.The activity order of the coordination atoms is carboxyl-Oamino-Nhydroxy-Oimino-Ncarbonyl-O;With the effect on glycylglycine by Cu(Ⅱ),the carboxyl-H and amino-H is prone to be protonated.