Synthesis and reactivity studies on new copper(II) complexes: DNA binding, generation of phenoxyl radical, SOD and nuclease activities.

Tridentate ligand PhimpH binds to Cu(II) centre after deprotonation affording a new family of complexes [Cu(Phimp)(H(2)O)](2)(ClO(4))(2) (1), [Cu(Phimp)(2)] (2) and [Cu(Phimp)(L)] (3-5) where L are CH(3)COO(-), SCN(-) and NO(2)(-) respectively. The molecular structures of complexes 1 x CH(3)CN and 3 were determined by X-ray crystallography. Electrochemical studies depicted Cu(II)/Cu(I) couple in the range of -0.50 to -0.65 V vs. Ag/AgCl. EPR spectral studies for complexes 4 and 5 indicated the order of covalent character in 4 > 5 with d(x(2)-y(2)) ground state. Novel copper complexes were synthesized by a tridentate ligand having phenolato, pyridine and azomethine nitrogen donors. Phenoxyl radical complexes were generated; DNA interaction, SOD and nuclease activities were investigated. [corrected] 2010 Elsevier Masson SAS. All rights reserved.