Synthesis, crystal structure and DNA interaction studies on mononuclear zinc complexes

A new family of mononuclear Zn(II) complexes [Zn(Pyimpy)2](ClO4)2 (1), [Zn(Pyimpy)(Cl)2] (2), [Zn(Pyimpy)(SCN)2] (3) and [Zn(Pyimpy)(N3)2] (4) were synthesized using designed tridentate ligand Pyimpy having NNN donors (Pyimpy: (2-((2-phenyl-2-(pyridin-2-l)hydazono)methyl)pyridine)). Complexes were characterized by different spectroscopic studies and it has been found out that all complexes exhibited strong fluorescent emission at room temperature. Molecular structures of [Zn(Pyimpy)2](ClO4)2·C6H5CH3·0.5H2O (1·C6H5CH3·0.5H2O) and [Zn(Pyimpy)(Cl)2]·CH3CN (2·CH3CN) were determined by X-ray crystallography and ligand coordinated Zn(II) ions was described as distorted octahedral and distorted square pyramidal, respectively. DNA binding properties of these complexes were investigated by absorption spectral, fluorescence quenching and circular dichroism spectral studies.