Synthesis, characterization, antimicrobial, DNA binding, and oxidative cleavage activities of Cu(II) and Co(II) complexes with 2-(2-hydroxybenzylideneamino)isoindoline-1,3-dione

(E)-2-(2-hydroxybenzylideneamino)isoindoline-1,3-dione (Hbid) was prepared by condensation of N-aminophthalimide and salicylaldehyde and characterized by elemental analysis, IR, 1H-NMR, and mass spectral studies. Mononuclear complexes [(phen)CuII(-Hbid)2H2O] (1), [(phen)CoII(Cl)2(-Hbid)]6H2O (2) (phen = 1,10-phenanthroline) and binuclear complexes [CuII(-Hbid)]2 (3), and [CoII(-Hbid)]2 (4) with Hbid were prepared and characterized by elemental analysis, IR, UV-Vis, molar conductance, and thermogravimetric (TG) techniques. DNA-binding properties of 1-4 were investigated by UV spectroscopy, fluorescence spectroscopy, and viscosity measurements. The results suggest that 1 and 2 bind to DNA by partial intercalation, whereas 3 and 4 find different groove-binding sites. The cleavage of these complexes with super coiled pUC19 has been studied using gel electrophoresis; all the complexes displayed chemical nuclease activity in the absence and presence of H2O2 via an oxidative mechanism. Complexes 1-4 inhibit the growth of both Gram-positive and Gram-negative bacteria.