Abstract

Synthesis, Characterization and Bioactivity Study of Novel Benzamides and their Copper and Cobalt Complexes

Author(s): Elija Khatiwora, Pranaya Joshi, Vedavati G. Puranik, Dipti Darmadhikari, Anjali Athawale, N. R. Deshpande and R. V. Kashalkar

Metal complexes of four new benzamides, [N-(3’-nitrophenyl) (piperidin-1"-yl) methyl] benzamide, [N-(piperidin-1"-yl) (p-tolyl) methyl] benzamide, [N-(4’-chloro-phenyl) (piperidin-1"-yl) methyl] benzamide and [N-(4’-methoxy-phenyl) (piperidin-1"-yl] benzamide derived by the condensation of benzamide, piperidine and substituted benzaldehydes have been synthesized. The structural features of the newly synthesized compounds have been determined from their micro analytical, IR, NMR, UV-Vis, Mass, and ESR spectral and thermal analysis data. [N-(piperidin-1"-yl) (p-tolyl) methyl] benzamide ligand was analysed by single crystal X-ray diffraction. All the Cu (II) complexes exhibited octahedral and Co (II) complexes showed tetrahedral geometry. Magnetic susceptibility measurements and low conductance data provided evidence for the monomeric and non-electrolytic nature of the complexes, respectively. The electrochemical behavior of the complexes in acetonitrile at room temperature was studied. All synthesized compounds were evaluated for in vitro antibacterial activity against the bacterial strains: Escherichia coli, Klebseilla pneumoniae, Bacillus subtilis, Staphylococcus aureus, Bacillus cereus, Proteus mirabilis and Pseudomonas aeruginosa. The results were compared with standard antibiotic ampicillin and streptomycin. The copper complexes exhibited better activities than that of the free ligands and standard ampicillin against all bacteria. As compared to streptomycin, these were more active against bacteria Bacillus cereus, ProteuS mirabilis and Pseudomonas aeruginosa.