New Metal Complexes of Thiosemicarbazone Mannich base Ligand; Synthesis, Structural Characterisation and Biological Activity

The synthesis of a new tridentate Schiff-base thiosemicarbazone ligand (HL) that derived from the reaction ((R)-2-((4-(dimethylamino)phenyl)((2-nitrophenyl)amino)methyl)-5,5-di methyl- cyclohexane-1,3-dione with thiosemicarbazide is reported. title ligand(E)-2-((R)-2-((R)-(4-(dimethylamino)phenyl)((2-nitrophenyl)amino)methyl)-5,5-dimethyl-3-oxocyclohexylidene)hydrazine-1-carbothioamide selected metal ions Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) gave monomeric complexes. Analytical spectroscopic techniques were used, as required, to characterise prepared compounds. These include; elemental microanalysis, 1H, 13C-NMR mass spectra, FT-IR electronic magnetic susceptibility conductance. analyses revealed formation complexes octahedral arrangement about Co(II); Cu(II) square planar tetrahedral geometry Ni(II) Zn(II); Cd(II)) ions, respectively. Thermal stability (TGA-DSC) HL also explored. antimicrobial activity compounds (ligand complexes) towards several microorganism (bacteria fungi species) examined. collected data was enhanced upon complex formation. Keywords: Thiosemicarbazone ligand, Metal complexes, Structural investigation, stability, Antimicrobial activity.