Synthesis,structure and properties of an imidazolate bridged copper,zinc binuclear complex

A new imidazolate bridged Cu~(2+),Zn~(2+)binuclear complex(dtma) CulmZn (dtma)]ClO_4·2.5H_2O taken as active site model for Cu,Zn-SOD has been synthesized and its crystal structuredetermined.All the bond lengths, bond angles and the distance between Cu and Zn atoms in Cu-Im-Zn core of the model complex are close to those in Cu,Zn-SOD.ESR parameters of the modelcomplex as a function of pH show that the imidazolate bridge is stable in pH range 10—12,and isbroken on Zn side at pH～9.With decreasing pH,the imidazole is released at pH～4 and the dtmaligand dissociates from the Cu containing fragment at pH～2.4.

Synthesis,structure and properties of an imidazolate bridged copper,zinc binuclear complex

A new imidazolate bridged Cu²⁺, Zn²⁺ binuclear complex (dtma) CuImZn (dtma)]ClO₄ · 2.5H₂O taken as active site model for Cu, Zn-SOD has been synthesized and its crystal structure determined. All the bond lengths, bond angles and the distance between Cu and Zn atoms in Cu-Im-Zn core of the model complex are close to those in Cu, Zn-SOD. ESR parameters of the model complex as a function of pH show that the imidazolate bridge is stable in pH range 10–12, and is broken on Zn side at pH ～9. With decreasing pH, the imidazole is released at pH ～4 and the dtma ligand dissociates from the Cu containing fragment at pH ～2.4.