SYNTHESIS, SPECTROSCOPIC DETERMINATION AND ANTIMICROBIAL STUDIES OF SCHIFF BASE DERIVED FROM 4-PHENYLTHIOSEMICARBAZIDE WITH 2- ACETYLPYRIDINE AND ITS Co(II) AND Ni(II) COMPLEXES

Abstract

ABSTRACT Condensation of 4-phenylthiosemicarbazide with 2-acetylpyridine in (1:1 molar ratio) ethanol produced Schiff base (2)-N-phenyl-2-[1-(pyridin-2-yl)ethylidene]hydrazine-1-carbothioamide (AP-PTSC). Interaction of the Schiff base with each of Co(II) and Ni(II) metal salts in (2:1 molar ratio) ethanol produced the Schiff base metal(II) complexes. The Schiff base and its Co(II) and Ni(II) complexes were characterized based on melting point/decomposition temperature, solubility, magnetic susceptibility, infrared spectra, molar conductance measurements, elemental and gravimetric analyses. The Co(II) and Ni(II) metal complexes show moderate values of decomposition temperatures The Schiff base and the complexes were soluble in some common organic solvents. Infrared spectral data of the Schiff base and its complexes, indicated coordination of the Schiff base to the metal(II) ion via azomethine nitrogen. The effective magnetic moment of the Co(II) and Ni(II) complexes suggested an octahedral geometry. The molar conductance values of the complexes show that the complexes are electrolytes. The results of the elemental analysis of the ligand and its complexes are in good agreement with the calculated values, suggesting a 1:2 (metal-ligand) ratio. Antimicrobial screenings of the ligand and its complexes were conducted against against gram-positive (Staphylococcus aureus,) and two gram-negative (Salmonella typhii, and Escherichia coli) bacteria specie. Also three fungi mainly (Candida albicans, Mucus indicus and Aspergillus flavus) were used. The results showed that both the ligand and the complexes are active against the specie used.