Synthesis, characterization, antimicrobial and antioxidant activity of 2-hydroxy-4-methoxybenzaldehyde-4-phenylthiosemicarbazone and its Pd(II), Ni(II) and Cu(II) complexes having heterocyclic bases

Abstract

The Schiff base ligand 2-hydroxy-4-methoxybenzaldehyde-4-phenylthiosemicarbazone (HMBPTSC) and its Pd(II) complex was presented. The Cu(II) and Ni(II) mixed ligand complexes with HMBPTSC, heterocyclic bases (2,2-bipyridyl, 1,10-phenthroline) and bisdiphenylphosphinomethane respectively were reported.  The ligand and metal complexes were characterized by LCMS, NMR and FT-IR & UV-Vis studies which clearly indicated the formation of metal complexes. EPR spectral studies were carried out for Cu(II) complexes, and single crystal XRD studies were presented for the Ni(II) complex. The results revealed that Cu(II) complexes were of elongated tetragonal and Ni(II) and Pd(II) were of square planar geometry. The ligand HMBPTSC and all the prepared complexes were tested for their biological activities. The evaluated antimicrobial, antifungal, and antioxidant activity of the ligand and metal complexes were compared with the standard drugs.