Structural and biological studies of mononuclear palladium(II) complexes containing N-substituted thiosemicarbazones

New complexes of Pd(II) with N-substituted thiosemicarbazone (1)-(3) have been synthesised and characterised by elemental analyses, IR, electronic. H-1 NMR spectroscopies. The electrochemical behaviour of the complexes has been tested by using cyclic voltammetry. The crystal structures of the complexes have been determined by single crystal X-ray diffraction technique. In all the complexes the thiosemicarbazone ligand is coordinated to palladium through ONS mode. The complex 1 crystallises in the monoclinic space group P2(1)/c with two molecules per unit cell, has the dimensions of a = 9.4390(19) angstrom, b = 10.645(2) angstrom, c = 13.668(3) angstrom, alpha = 90 degrees, beta = 91.43 degrees and gamma = 90 degrees. The complex 3 crystallises in the monoclinic space group P2(1)/c with four molecules per unit cell, has the dimensions of a = 14.119(3) angstrom, b = 11.155(2) angstrom, c = 18.503(4) angstrom, alpha = 90 degrees, beta = 112.02 degrees and gamma = 90 degrees. The new complexes have been tested for their antibacterial activity against various pathogenic bacteria. From this study, it was found out that the activity of the complex 2 almost reaches the effectiveness of the conventional bacteriocide Streptomycin. (c) 2007 Elsevier Masson SAS. All rights reserved.