Synthesis, Characterization and Biological Activity of Salicylaldehyde-Thiosemicarbazone and Its Metal Complexes

Abstract

The Cr (III), Co (II), Ni (II) and Cu (II) complexes of the ligand salicylaldehyde thiosemicarbazone (STSC) were prepared and different analytical techniques such as Atomic Absorption Spectroscopy (AAS), Ultra Violet Spectroscopy (UV) and Infra-Red Spectroscopy (IR) were used to characterize the obtained products. The obtained result of the ligand alone and the metals as complexes indicate the existence of monoanionic tridentate nature of ligand, which undergo coordination to metal ions with oxygen, nitrogen and sulfur (ONS) donor atom sets. The antimicrobial activity of the ligand salicylaldehyde thiosemicarbazone and its Cr (III), Co (II), Ni (II) and Cu (II) complexes were conducted against various microbes like the species Staphlococcus aureus, Escherichia coil and Candida albicans, effect of the investigated compounds have been tested by the disc diffusion method. A comparative study of inhibition values of the Schiff base ligands and their complexes indicated that the biological activity for the ligand alone was lower than the complexes form. The ligand have no activity against Staphlococcus aureus, Escherichia coil and Candida albicans , the complexes have highly activity against Staphlococcus aureus, Escherichia coil, complex of Ni (II) have activity against Escherichia coil, and complex of Cr (III) have activity against Staphlococcus aureus, the complex of Co(II) has no activity against Staphlococcus aureus, Escherichia coil and Candida albicans .