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

Abstract New complexes of Pd(II) with N -substituted thiosemicarbazone ( 1 )–( 3 ) have been synthesised and characterised by elemental analyses, IR, electronic, 1 H 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 P 2 1 / c with two molecules per unit cell, has the dimensions of a  = 9.4390(19) A, b  = 10.645(2) A, c  = 13.668(3) A, α  = 90°, β  = 91.43° and γ  = 90°. The complex 3 crystallises in the monoclinic space group P 2 1 / c with four molecules per unit cell, has the dimensions of a  = 14.119(3) A, b  = 11.155(2) A, c  = 18.503(4) A, α  = 90°, β  = 112.02° and γ  = 90°. 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 .