Synthesis, Characterization, and Antibacterial Activity Evaluation of New Co(II),Ni(II),Cu(II) and Zn(II) Complexes with Tridentate Hydrazones

Abstract

Hydrazones derived from acid hydrazides and 2-benzoylpyridine namely; 2-benzoylpyridineacetyl hydrazine (BPAH),2-benzoylpyridine-4-methylbenzoyl hydrazone (BPMH) and 2-benzoylpyridine picolinoylhydrazone (BPPH) have been synthesized and used to prepar the corresponding Co(II), Ni(II), Cu(II) and Zn(II) complexes. The ligands undergo deprotonation forming neutral mononuclear octahedral bis-complexes of the type [M(L-H)2] where L-H = deprotonated BPAH, BPMH or BPPH, acting as uni-negative tridentate ligands. The complexes isolated were characterized by elemental analyses, (IR, electronic spectra), molar conductance and magnetic susceptibility measurements. The bonding and probable structure of ,the complexes are discussed depending on the basis of the spectral and magnetic data. The ligands, as well as some of their complexes, screened against eight Gram-positive and Gram-negative bacteria, The tested compound exhibited moderate activity with respect to ceftriaxone antibiotic and higher activity than the free ligands.