Ligand Field Parameters of Some Transition Metal Ion Complexes of Some Substituted Hydrazones and their Antibacterial Activity

Potentiometric studies have been carried out on transition metal complexes of Mn+2, Co+2, Ni+2, Cu+2, Zn+2 with hydrazones synthesized from 4-amino benzoic acid hydrazide and 2-hydroxy-1acetonephthone/2-hydroxy-1-naphthaldehyde. The dissociation constants of ligand and formation constants of its metal complexes have been determined by Calvin-Bjerrum pH titration technique, as adopted by Irving and Rossotti at 27±0.1oC and at an ionic strength of 0.1M in 60:40 (v/v) dioxane water medium. The order of the stability of complexes is Cu+2 > Ni+2 > Co+2 > Mn+2 > Zn+2 for both the ligand AHNEH and AHNMH. All the metal complexes screened for their antibacterial activity. The result indicates that the growth of the tested organism was inhibited by most of the compounds.