Geometrical structures, thermal properties and spectroscopic studies of Schiff base complexes: Correlation between ionic radius of metal complexes and DNA binding

A novel series of transition metal complexes of Cu (II), Co (II), Ni (II), Mn (II) and Cd 
(II) were prepared from Schiff base derived from 4-aminoantipyrine and quinoline-2-
carbaldehyde to give 4-((quinolin-2-yl) methyleneamino)-1, 2-dihydro-2, 3-dimethyl-1-
phenylpyrazol-5-one (QMP). The structural features were derived from elemental analysis, 
mass spectroscopy, X-ray, IR, 1 H NMR, electronic spectra, molar conductance magnetic 
susceptibility and thermogravimetric studies. On the basis of the studies the coordination 
sites were proven to be through oxygen of the ring CO and nitrogen of the azomethine 
(HCN) group. The thermodynamic parameters were calculated using Coats–Redfern and 
Horowitz–Metzger methods