Structure and biological profile of transition metal complexes with (E)-4-(2-(pyridin-2-ylmethylene)hydrazinyl)quinazoline

The interaction of the recently reported quinazoline derivative (E)-4-(2-(pyridin-2-ylmethylene)hydrazinyl)quinazoline (L) with a series of metal(II) (= copper(II), nickel(II), cobalt(II) and cadmium(II)) chlorides or nitrates resulted in the formation of mononuclear complexes which were characterized by spectroscopic techniques and single-crystal X-ray crystallography, i.e. [Cu(L)2]Cl2·4H2O (1·4H2O), [Ni(L)2]Cl2·4H2O (2·4H2O), [Ni(L)2](NO3)2·MeOH (3·MeOH), [Co(L)2]Cl2·4H2O (4·4H2O), [Co(L)2](NO3)2·H2O (5·H2O), [Co(L)2](NO3)3·2.5H2O (6·2.5H2O), [Cd(L)(Cl)2]·H2O (7·H2O) and [Cd(L)(CH3OH)(H2O)(NO3)](NO3) (8). The biological profile of the complexes was further assessed in regard to their binding affinity with calf-thymus DNA, their cleavage ability towards pBluescript II KS plasmid DNA in the absence or presence of irradiation of various wavelengths, their interaction with bovine serum albumin and finally, their ability to scavenge 1,1-diphenyl-picrylhydrazyl and 2,2΄-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radicals and to reduce H2O2. Eight metal complexes with (E)-4-(2-(pyridin-2-ylmethylene)hydrazinyl)quinazoline as ligand were prepared, characterized by X-ray crystallography and evaluated for their ability to interact with calf-thymus DNA, to (photo)cleave plasmid-DNA, to bind to bovine serum albumin, to scavenge free radicals and to reduce hydrogen peroxide. [Display omitted] •Eight metal complexes of hybrid quinazoline ligand were prepared and characterized.•Intercalation is the most possible binding mode of the complexes to calf-thymus DNA.•The complexes can photo-cleave plasmid DNA.•The complexes may bind tightly and reversibly to bovine serum albumin.•The complexes exhibit significant ability to reduce H2O2.