Synthesis, Characterization and Antimicrobial Screening of Novel Hydrazide Ligand & It’s Transition Metal Complexes

Abstract

Different transition metal complexes were synthesized from novel 3-bromo-2-[1-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)ethylidene]hydrazide ligand (H2L) and characterized by spectral techniques. The synthesized ligand was found to act mono as well as di deprotonated (OH, NH) manner and stoichiometry of the ligand to metal ions was confirmed to be 1:1 in case of complex using metal chloride salts, whereas 1:2 in case of metal(II) complexes using metal acetate(II) salt. Structures of metal complexes were confirmed by IR, 1H NMR, TGA, XRD, elemental analysis and UV technique which revealed that Mn(II), Co(II), Ni(II), Cu(II) complexes were octahedral geometry and those of Cu(II), Zn(II) showed square planner and tetrahedral geometry around metal ion respectively. Furthermore H2L and its metal complexes were screened for antimicrobial activity which showed that ligand enhanced its biological activity after coordination with metal ions. In particular, Cd(II) and Mn(II) complexes exhibited excellent antifungal activity.

Synthesis, Characterization and Antimicrobial Activity of Ni(II), Zn(II), and Cd(II) Complexes of 3/4-Bromo-Benzoic Acid (Phenyl-Pyridine-2-yl-Methylene)-Hydrazide Ligand

“…The presence of the heterocyclic ring in synthesized ligands extends their pharmacological properties as well as provide an additional binding site to the metal ions [19]. In view of the important role of metal complexes of 2-benzoyl pyridine Schiff bases in biological systems, their structural properties [20][21][22][23] and in continuation of our efforts in the development of new metal complexes [24]; in the present article, we report synthesis, characterization and antimicrobial activity of [Ni(L)2], [Zn(L)Cl], [Zn(L)2], and [Cd(L)2] complexes with 3,4-bromo-benzoic acid (phenyl-pyridin-2-yl-methylene)-hydrazide ligand (Scheme 1). Scheme 1.…”