E.P.R. study of an imidazolate-bridged Cu-Zn complex of glycylglycine

Department of Chemistry, A.P.S. University, Rewa (M.P.) 486003, India
Journal of Inorganic Biochemistry 01/1998; 72:109-114. DOI: 10.1016/S0162-0134(98)10062-4

ABSTRACT An imidazolate-bridged heterometallic binuclear copper–zinc complex Na[(glygly)Cu–im–Zn(glygly)], where H2glygly is glycylglycine and imH is imidazole, has been synthesized. X-band e.p.r. spectra of the complex at different pH values in frozen solution (50% DMSO, 77 K) suggest that the imidazolate bridged complex is stable in the pH range 7–10. At lower pH (<7) the imidazolate bridge breaks on the copper side. At higher pH (>10), the e.p.r. changes suggest either hydroxylation of the copper centre or breaking of the imidazolate bridge on the zinc side.

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