Synthesis and characterization of some pyrimidine, purine, amino acid and mixed ligand complexes

MnII, FeIII, CoII, NiII, CuII, ZnII and CdII complexes of barbital, thiouracil, adenine, amino acids (methionine, lysine and alanine) and some mixed ligands were prepared and characterized by elemental analyses, IR, electronic spectra, magnetic susceptibility and ESR spectra. Coordination of the metallic centre to the oxygen and nitrogen atoms of barbital, thiouracil, amino acids and coordinate to amino group and nitrogen atom of adenine occurred. Electronic spectra and magnetic susceptibility measurements were utilized to infer the structure of the complexes which are octahedral for MnII, FeIII, CoII, NiII and CdII and tetrahedral for MnII, CuII, ZnII complexes. ESR spectra were observed for copper complexes with a dx2−y2dx2−y2 ground state with small g|| values indicating strong interaction between the ligands and their metal ions.