Synthesis,characterization, and DNA-binding of a four-coordinate cobalt(II) complex with 1,3-bis(1-ethylbenzimidazol-2-yl)-2-oxopropane

A new four-coordinate cobalt(II) complex with 1,3-bis(1-ethylbenzimidazol-2-yl)-2-oxopropane (Etobb), Co(Etobb)Cl₂, has been synthesized and characterized by elemental analysis, electrical conductivities, infrared, and UV-Vis spectral measurements. The crystal structure has been determined by single-crystal X-ray diffraction. Cobalt(II) is a distorted tetrahedral geometry, surrounded by two nitrogens from Etobb and two chlorides. DNA-binding properties of Etobb and its Co(II) complex have been investigated by electronic absorption, fluorescence, and viscosity measurements. The experimental results suggest that the ligand and its Co(II) complex bind to DNA via intercalation, and the binding affinity of the Co(II) complex to DNA is greater than Etobb.