Study of Coordination Mode of Bidentate Ligands Derivative of 2-Benzoylpyridine Thiosemicarbazone, 2-Benzoylpyridine semicarbazone, and 2-Benzoyl thiophene thiosemicarbazone and their Co(II) complexes : Synthesis, Characterization, and their Biological Ac

Meenakshi Gupta, Bhupendra Kumar Sarma, S.Chandra, Sangeeta Gupta, Sanjay Singhal


Objective: To study the synthesis, characterization and biological activity of Co(II) complexes.

Material and Method: All the complexes and ligands were prepared by reflux for 7-8 hrs. Ethyl alcohol was used as solvent and pH was adjusted in the range of 3-4 in case of 1,3 ligands. Round bottom flask, heating mentle, glass rod, condenser were used for the experiment.

Result: Co(II) complexes of general composition [Co(L2)X2] have been synthesized (from Schiff base ligands of thiosemicarbazone , semicarbazone and 2-benzoylpyridine, 2-benzoylthiophene) where L = 2-benzoylpyridinethiosemicarbazone ligand (L1), 2-benzoylpyridine and semicarbazone ligand (L2), 2-benzoylthiophenethiosemicarbazone ligand (L3) and X = NO3-, ½SO42-, OAc- and Cl-. All the complexes and ligands under study were characterised by IR, NMR, elemental analysis, mass spectroscopy, EPR and UV spectroscopy and magnetic susceptibility. The various physico chemical technique suggests octahedral geometry for chloro, acetato and nitrato complexes and five coordinated trigonal bipyramidal geometry for sulphato complexes. The magnetic moment values suggests three unpaired electrons and high spin type complexes. The complexes under study were screened against bacteria and pathogenic fungi in vitro.

Conclusion: The synthesised ligands were bidentate and complexes were found more active towards antimicrobial activity than ligands.     

Keywords: Mass, IR, NMR, EPR,  thiosemicarbazide , semicarbazone