Pyridyl–tetrazole ligands 2-(5-(pyridin-2-yl)-1H-tetrazol-1-yl)acetamide (L1), 2-(5-(pyridin-2-yl)-2H-tetrazol-2-yl)acetamide (L2), 2-(5-(pyridin-2-yl)-1H-tetrazol-1-yl)acetohydrazide (L3) and 2-(5-(p Show more
Pyridyl–tetrazole ligands 2-(5-(pyridin-2-yl)-1H-tetrazol-1-yl)acetamide (L1), 2-(5-(pyridin-2-yl)-2H-tetrazol-2-yl)acetamide (L2), 2-(5-(pyridin-2-yl)-1H-tetrazol-1-yl)acetohydrazide (L3) and 2-(5-(pyridin-2-yl)-2H-tetrazol-2-yl)acetohydrazide (L4) have been prepared and coordinated with CuCl2·2H2O to furnish the corresponding complexes [Cu(L1) 2 ]–[Cu(L4) 2 ]. EPR spectra of the complexes are characteristic of square planar geometries, with nuclear hyperfine spin 3/2. DNA-binding studies using UV–Vis absorption spectroscopy, viscosity and thermal denature studies revealed that all of these complexes are avid binders of calf thymus DNA. The antioxidant properties of the free ligands and the Cu(II) complexes were investigated using the p-nitrosodimethyl aniline hydroxyl radical scavenging method, and [Cu(L4) 2 ] was found to show the highest activity. Show less