Preparation, characterization and Microbicide activities of N'-((3-(hydroxyimino)butan-2-ylidene)-2-(phenylamino)acetohydrazide and its complexes

Abstract

A series of fourteen metal complexes synthesized by reaction a new acetohydrazide oxime ligand with metal ions (CuII, NiII, CoII, MnII, FeIII, ZnII, RuIII, UO2VI and VO2VI). The Ligand, N''-((3-(hydroxyimino)butan-2-ylidene)-2-(phenylamino)acetohydrazide was prepared by refluxing 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) and (10-12) were formed in 1L:1M molar ratio, while complexes (4), (8), (9), (13) and (14) were found to afford M2L formulae. The ligand acted either as a neutral bidentate, neutral, monobasic or dibasic tridentate and dibasic tetradentate ligand chelated 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 aoctahedral, 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 Aspergillum 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, 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.