Abstract
A SERIES of thirteen metal complexes was synthesized by reaction a new acetohydrazide oxime ligand with some metal ions (Cu2+, Ni2+, Co2+, Mn2+, Fe3+, Zn2+, Ru3+, UO22+ and VO3-). The ligand, N'-((3-(hydroxyimino) butan-2-ylidene)-2-(phenylamino) acetohydrazide was prepared by refluxing an equimolar amount of phenyl amino acetohydrazide with 2,3-butanedione monoxime. The synthesized compounds were characterized using elemental and thermal analyses, NMR, IR, U.V spectroscopy, magnetic and conductance measurements. The results demonstrated that complexes (2), (3), (5-7), (10) and (12) were formed in 1L: 1M molar ratio. Complexes (4), (8), (9), (13) and (14) were found to afford M2L formulae while complex (11) adopted ML(2)formulae. The ligand acted as a neutral (bidentate [11], tridentate [6,7], monobasic (tridentate [2,3,5,12]), dibasic (tridentate [10], tetradentate[4,8,9,13,14]) chelating to the metal ions via nitrogen atoms of aceto-amino and azomethine groups, carbonyl oxygen atom in its enolic or ketonic form and/or protonated or deprotonated oximino nitrogen atom, adopting an octahedral, tetrahedral or square planar geometry around metal ions. The antimicrobial activity of the ligand, as well as the metal complexes, was examined using Amphotericin B and Amoxicillin as drug-standards against Aspergillus niger (A. niger) and Escherichia coli (E. coli), respectively. The ligand demonstrates a high cytotoxicity against A. niger whereas it recorded a moderate activity against E. coli. It is interestingly found that zinc(II) complex (6), copper(II) complexes (8) and (10) recorded higher activities than the Amphotericin B drug with 122%, 116% and 111.1% percentages respectively against A. niger. Zinc(II) complex (6) was also the most sensitive complex against E. coli with (94.1 %) comparable to Amoxicillin.