Co(II), Ni(II), Cu(II) and Zn(II) Complexes of 4-(4-cyanobenzylideneamino)-3-mercapto-5-oxo-1,2,4-triazine: synthesis, characterization and biological studies

A new series of metal complexes have been synthesized with an imine 4-(4-cyanobenzylideneamino)-3-mercapto-5-oxo-1,2,4-triazine which has been derived by the condensation of 4-cyanobenzaldehyde and 4-amino-3-mercapto-5-oxo-1,2,4-triazine. Different techniques like IR, H-1 NMR, electronic spectroscopy, fluorescence, ESR, thermal, conductivity and magnetic measurements were used to investigate the structural features of the synthesized compounds. Based on spectral and thermal techniques, octahedral geometry has been proposed for Co(II), Ni(II) and Zn(II) complexes and square planar for Cu(II) complexes. All the synthesized metal complexes show enhancement in fluorescence intensity in comparison to the ligand. The newly synthesized ligand and metal complexes were also screened for their antimicrobial activities against some bacterial and fungal strains to assess their inhibiting potential in vitro. The activities shown by these complexes were compared with ligand and also with standard drugs. The molar conductivity values indicate that the complexes are non-electrolytes.