Synthesis, Characterization, Spectral (FT-IR, 1H, 13C NMR, Mass and UV) and Biological Aspects of the Coordination Complexes of Sulfur Donor Ligands with Some Rare Earth Elements

Abstract

Bio-potent ligands, 2-hydroxy-N-phenylbenzamide hydrazinecarbothioamide(HPHTSCZH2) and 2-hydroxy-N-phenylbenzamide hydrazine carbodithioic benzyl ester (HPHCBESH2) have been synthesized by the condensation of 2-hydroxy-N-phenylbenzamide with hydrazinecarbothioamide and hydrazine carbodithioic benzyl ester, respectively and reacted with hydrated lanthanide chlorides.  The coordination moieties of the ligands have been confirmed by various spectral studies. Elemental analyses suggested  that the complexes have 1:2 stoichiometry which were characterized further by magnetic moment, infrared, EPR, electronic, 1H NMR, 13C NMR and mass spectral studies. TGA studies were also conducted for one of the representative compound to analyze the presence of water molecule. The spectral studies confirmed the proposed framework of the new lanthanide complexes and indicated an octahedral geometry around the central metal atom. On the basis of X-ray powder diffraction study one of the representative  Sm complex was found to have Hexagonal Lattice type, having Lattice Parameters: a = 18.528 Aº,   b = 18.528 Aº and  c = 20.675 Aº and α = 90º, β = 90º and γ =120º. The free ligands and their metal complexes have been tested in vitro against a number of microorganisms in order to assess their antimicrobial properties and in vivo for antifertility activity on male albino rats. Both the ligands and their complexes were found to possess appreciable fungicidal, bactericidal and antifertility activities.