The mixed ligand complexes of Cu(II), Ni(II) and Co(II) with uridine and amino acids, L-alanine, L-phenylalanine and L-tryptophan were synthesized and characterized by elemental analysis, conductivity data, infrared spectra, electronic spectra and magnetic susceptibility data. In these complexes, the nucleoside (uridine) acts as a monodentate ligand coordinating through O(4) under the conditions of investigation, whereas the amino acids coordinate through the carboxylate oxygen and the amino nitrogen. Distorted octahedral geometry for Cu(II) and octahedral geometries for both Ni(II) and Co(II) are proposed.

Mixed ligand complexes of zinc(II) with uridine and aminoacids L-alanine, L-phenylalanine and L-tryptophan were synthesized and characterized by elemental analysis, conductivity data, electronic, IR, 1H-NMR and 13C-NMR spectra. In these complexes, the nucleoside (uridine) acts as a monodentate ligand coordinating through 0(4) under conditions of investigation whereas the aminoacids coordinate through carboxylate oxygen and amino nitrogen. The results drawn about binding sites of these octahedral complexes are compared with the results obtained from solution studies for a comprehensive understanding of the binding sites in these systems.

Mixed ligand complexes of Zn(II) with cytidine and amino acids, alanine, phenyl alanine and tryptophan were synthesized and characterized by elemental analysis, conductivity data, electronic spectra, IR, 1H NMR and 13C NMR spectra. In these complexes, the nucleoside acts as a monodentate ligand involving only N(3) in metal coordination whereas the amino acids coordinate through carboxylate oxygen and amino nitrogen. Conclusions drawn about binding sites are compared with the results obtained from solution studies. Interestingly the results from solution and solid state are in agreement, thus providing an opportunity to rationalize the binding sites in these systems.