Manjula S. Patil

Transition metal complexes of a new hexadentate macroacyclic N2O4-donor Schiff base: Inhibitory activity against bacteria and fungi

A new hexadentate macroacyclic N(2)O(4) - donor ligand, glyoxal bis(N-nitroso phenylglycine) (gbnp), has been designed and structurally characterized. Manganese(II), cobalt(II), nickel(II), copper(II) and zinc(II) complexes of gbnp have been prepared and characterized by elemental analyses, molar conductance measurements, magnetic moment, spectral (IR, (1)H NMR, electronic and FAB mass) and thermal studies. The molecular dynamics of the ligand was studied by the variable temperature NMR studies, which suggest the presence of two isomeric forms. The antimicrobial activity of all the compounds was studied against Escherichia coli, Bacillus cirroflagellosus, Aspergillus niger and Candida albicans. Among the new complexes, copper(II) complex has the highest potential against all the microorganisms tested.

Synthesis, characterization of copper(II), cobalt(II), nickel(II), zinc(II) and cadmium(II) complexes of [7-hydroxy-4-methyl-8-coumarinyl]glycine and a comparitive study of their microbial activities

A new Mannich base, [7-hydroxy-4-methyl-8-coumarinyl]glycine [MCGH(2)], has been prepared by the condensation of 7-hydroxy-4-methyl-coumarin with glycine and formaldehyde. Its conformational changes on complexation with transition metal ions [copper(II), cobalt(II), nickel(II), zinc(II) and cadmium(II)] have been studied on the basis of elemental analysis, conductivity measurements, spectral (infrared, (1)H NMR, electronic, EPR), magnetic and thermogravimetric studies. The infrared spectral studies of all the complexes reveal that the ligand has coordinated through -NH and two hydroxyl groups. The conductance data of the complexes suggest them to be non-electrolytes. Fluorescence property of the ligand and its metal complexes was studied and concluded that the ligand MCGH(2) can be a potential candidate for the determination of zinc(II) and cadmium(II) at room temperature by fluorimetric method. The antimicrobial activity of all the compounds was studied against Gram negative (Escherichia coli) and Gram positive (Bacillus cirroflagellosus) bacteria and fungi, Aspergillus niger and Candida albicans. It was observed that the coordination of metal ion has a pronounced effect on the microbial activities of the ligand. All the metal complexes have shown higher antimicrobial effect than the free ligand.

Lanthanide(III) and Yttrium(III) Complexes of Benzimidazole-2-Acetic Acid: Synthesis, Characterisation and Effect of La(III) Complex on Germination of Wheat.

The synthesis and characterisation of lanthanide(III) and yttrium(III) nitrate complexes of benzimidazole-2-acetic acid (HBIA) are reported. The complexes have been characterised by elemental analysis, molar conductance, magnetic studies, IR, 1H NMR, UV-visible, EPR, and TG/DTA studies. They have the stoichiometry [Ln3(BIA)2(NO3)7(H2O)4] · 3H2O where Ln=La(III), Pr(III), Nd(II), Sm(III), Eu(III), Gd(III), Tb(III), Dy(III), and Y(III). The effect of La(III) complex on germination, coleoptile, and root length of two local varieties of wheat DWR-195 and GW-349 for different treatment periods has been investigated. The complex was found to exhibit enhanced activity, compared to HBIA or metal salt alone at lower treatment periods.