Synthesis, characterization and antimicrobial activities of schiff base derived from thiourea and anisaldehyde and its Mn(II), Fe (II) and Co(II) complexes

Abstract

Complexes of Mn(II), Fe(II) and Co(II) with a Schiff base derived from condensation reaction of thiourea and o-anisaldehyde has been synthesized and characterized analytically and spectroscopically. Melting point of the Schiff base was found to be 160°C and the complexes decomposed within a temperature range of 215 to 275°C. Molarconductances of the complexes were found to be within 1.1 to 3.5W^–1 cm² mol^–1 range. Magnetic moment indicated the complexes to be paramagnetic (4.03 to 5.71BM). Infrared spectrum of the Schiff base showed the azomethine peak at 1601cm^–1 which shifted up to1687cm^–1 in the complexes. The analytical and spectral studies revealed that all the metal(II) complexes are in 1:3 metal ligand ratio, with the Schiff base acting as tetradentate ligand towards the metal ion via azomethine – N, and methoxy –O and two chlorine atoms were further coordinated to the metal(II) ion. The synthesized ligand and its respective metal (II) complexes were screened for their antibacterial activity against Staphylococcus aureus and Escherichia coli strains and antifungal activity against Aspergillus flavus and Mucorindicus. The results revealed that, the Schiff base and the metal (II) complexes showed significant antibacterial and antifungal activities at high concentration.

Keywords: Metal complexes, thiourea, anisaldehyde, characterization, antimicrobial