Coordination Compounds of Nickel(II) with 3,5–Dibromo–Salicylaldehyde: Structure and Interaction with Biomolecules

Three neutral nickel(II) complexes of 3,5–dibromo–salicylaldehyde (3,5–diBr–saloH) were synthesized in the presence or absence of 1,10–phenanthroline (phen) or its derivative 2,9–dimethyl–1,10–phenanthroline (neoc) as co–ligands, namely [Ni(3,5–diBr–salo)2(neoc)] (complex 1), [Ni(3,5–diBr–salo)2(phen)] (complex 2) and [Ni(3,5–diBr–salo)2(H2O)2] (complex 3), and were characterized by various techniques. The crystal structure of [Ni(3,5–diBr–salo)2(neoc)] was determined by single-crystal X-ray crystallography. According to employed studying techniques, the complexes interact tightly with calf-thymus DNA by an intercalative fashion. Furthermore, compounds 1–3 bind tightly and reversibly to human and bovine serum albumin.