Spectroscopic, Characterization and Biological Studies of Pyridine Carboxyamide Complexes

Newly synthesized carboxyamide ligand N,N'-bis(2-carboxy-1-oxophenelenyl) pyridine 2,6- diamine and their Co(II), Ni(II) and Cu(II) complexes have been synthesized and characterized by various physico-chemical techniques. Vibrational spectra indicate coordination of amide and carboxylate oxygen of the ligand. Mass spectrum explains the successive degradation of the molecular species in solution and justifies ML complexes. The electron paramagnetic resonance of the Cu(II) complex shows g║ > g > 2.03 was observed indicated that unpaired electron most likely reside in the dx 2 -y 2 ( or less likely a dxy) ground state, which is consistent with the proposed square based geometry. Electronic spectra and magnetic susceptibility measurements reveal square planar geometry for metal complexes. Molecular structure of the complexes has been optimized by MM + calculations and supports a square planar geometry. The bio-efficacy of the ligands and its metal complexes has been examined against the growth of bacteria in vitro to evaluate their anti-microbial potential.