A new series of Cu (II), Ni (II), Co (II) and Zn (II) complexes have been synthesized from the Schiff base derived from 4-hydroxy-3-methoxybenzylidine-4-aminoantipyrine and 2-aminophenol. The structural features have been determined from their elemental analysis, magnetic susceptibility, molar conductance, Mass, IR, UV-Vis,1H-NMR,13C-NMR and ESR spectral studies. The redox behavior of the copper complex has been studied by cyclic voltammetry. The data confirm that the complexes have composition of ML2type. The electronic absorption spectral data of the complexes propose an octahedral geometry around the central metal ion. All the metal complexes with DNA structure were guided by the presence of inter-molecular C–HO and C–HN hydrogen bonds. The biological activity of the synthesized compounds were tested against the bacterial species such asBacillus subtilis, Staphylococcus aureus, Proteus vulgarisand fungal species such asCandida albicansby thewell-diffusionmethod.

The kinetics of oxidation of aldonitrones by 4-(dimethylamino)pyridinium chlorochromate (DMAPCC) has been studied in aqueous N,N-dimethylformamide in the presence of perchloric acid. The reaction follows first-order kinetics with respect to each of DMAPCC and nitrone. The order with respect to [H + ] was found to be close to zero. The rate of oxidation was unaltered by the variation of [NaClO 4 ] but addition of MnSO 4 decreased the rate. The reaction rate was found to decrease with a decrease in dielectric constant of the medium. Electron-releasing and electron-withdrawing groups perturb the reaction rate with a good Hammett correlation. The oxidation products were found to be benzaldehyde and nitrosobenzene. The reaction was carried out at four different temperatures and the activation parameters have been calculated. On the basis of the experimental findings, a suitable mechanism has been proposed.

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The kinetics of the oxidation of aldonitrones (nitrone) by quinolinium chlorochromate (QCC) was determined in 50 % DMF-water in the absence and presence of oxalic acid in order to study the effect of oxalic acid. It was considered worthwhile to investigate whether it undergoes co-oxidation or just functions as a catalyst in the reaction. The reaction was followed iodometrically. Under the employed experimental conditions, the reaction is first order each with respect to concentration of nitrone, QCC, and oxalic acid and fractional order with respect to H+ concentration. There was no discernible effect with increasing in ionic strength but the rate of oxidation decreased with decreasing dielectric constant of the medium. Addition of MnSO4 had a significant and acrylonitrile no effect on the reaction rate. A mechanism involving protonated nitrone and QCC as the reactive oxidant is proposed. The activation parameters were calculated and are presented.

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