A series of novel binuclear transition metal complexes was synthesized by reaction of a Schiff base ligand 2-((1-methyl-2-((2-oxo-1,2-dihydro-pyrimidin-4-yl)imino)propylidene)amino)acetic acid) (L a H) derived from 4-amino-1H-pyrimidin-2-one, diacetyl, glycine and the corresponding chloride salt of Cu(II), Ni(II), Co(II) and Zn(II) metals in a 1:1 (metal:ligand) mole ratio. The compounds were characterized by elemental analyses, molar conductance measurements, magnetic moment measurements and various spectral studies viz. IR, UV-Vis, 1 H-NMR, 13 C-NMR, EPR and ESI-MS. The molar conductance measurements revealed the non-electrolytic nature of the metal complexes. Electronic absorption spectral data, electronic paramagnetic resonance parameters and magnetic moment values revealed an octahedral geometry for the binuclear metal complexes. A cyclic voltammetric study of Ni(II) complex shows a couple of one-electron anodic responses near 0.70 and 1.10 V. The in vitro biological activity of the Schiff base ligand and the binuclear complexes was assessed against bacteria (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Salmonella typhi) and fungi (Candida albicans and Candida parapsilosis) to ascertain their antibacterial and antifungal properties.

Some noble heterobinuclear complexes of transition metal ions with bis(salicylaldehyde)malonyl-dihydrazone in the presence of 5-nitroindazole Cu(II) / Ni(II)- chloride of the type [ML1M‘L2Cl2] or [ML1FeL2Cl2]Cl, where M = Ni(II), Cu(II) and M' = Mn(II), Co(II), have been prepared. All the complexes have been characterized by IR, UV vis and EPR spectroscopy, elemental analysis, magnetic moment and molar conductance measurement. Spectral studies and magnetic moment measurement in DMF suggest the covalent nature of the complexes, except the [ML1FeL2Cl2]Cl complex which is 1:1 electrolyte. An octahedral geometry is proposed for M‘ and square planer for M for the heterobinuclear complexes. The low value of magnetic moment and overlapping EPR signals are due to spin crossover since both of the metals have unpaired electrons with same molecular symmetry. The lowering of the magnetic moment has been discussed. The biological activity (antifungal and antibacterial) of the represented compounds has been studied.

CH3COO-and L = ligand) of a Schiff base ligand derived from 1-amino-5-methyl-2,6-pyrimidine-dione and 2,3-butanedione have been synthesized and characterized by elemental analysis, molar conductance measurements, magnetic moment measurements, IR, UV-visible, 1 H NMR, EPR and mass spectral studies. Electronic spectral data and magnetic moment values indicate octahedral geometry for all the metal complexes. In vitro antimicrobial activity of ligand and its metal complexes were also studied against bacteria (Bacillus subtilis and Escherichia coli) and fungi (Aspergillus niger and Aspergillus flavus) which show antimicrobial activity of ligand and binuclear metal complexes.