Synthesis, Spectroscopic Characterization and Antimicrobial Activity of Novel Azo-acetohydrazide Metal Complexes

A novel azo-ligand was synthesized by condensation of 2-hydroxy-5-(p-tolyldiazenyl) benzaldehyde, with 2-(phenylamino) acetohydrazide. The ligand as well as its complexes have been characterized by various spectroscopic and analytical techniques. The spectral data confirmed that the ligand adopted either a neutral bidentate or a dibasic tridentate mode, bonded to the metal ions through the oxygen atom of the carbonyl group, azomethine nitrogen atom and/or deprotonated phenolic oxygen atom forming either a tetragonally distorted octahedral, an octahedral or a square planer geometry. X-ray powder diffraction analysis of complexes [Cu(H2L)2Cl2].2H2O and [Cu(L)(H2O)3] indicated that the complexes are crystalline in nature and have monoclinic structures. The antibacterial as well as the antifungal activities of the ligand and its complexes were evaluated against Escherichia coli and Aspergillus niger by well- diffusion method. The results showed that complex [VO(H2L)2(SO4)]H2O exhibits the highest antifungal activity while complex [Cu(L)(H2O)3] exhibits the highest antibacterial activity among the tested complexes