MOROCCAN JOURNAL OF CHEMISTRY, cilt.5, sa.4, ss.560-572, 2017 (ESCI)
A new unsymmetric Schiff base [(2OH) R-CH=N-(C6H4)-CH=N-R'(2OH) R=phenyl, R' = naphthyl] with its Fe(III) and Ni(II) complexes were synthesized by a two step method. Diimine Schiff base and its complexes were characterized by elemental analysis, mass spectra, IR, H-1/C-13-NMR spectra, TGA analysis, electronic and magnetic measurements. The phenol-imine and keto-amine tautomerism of the unsymmetric Schiff base was investigated with NMR techniques and UV-visible spectra in different solvents. Also, the protonation constants of the ligand and the stability constants of its Ni(II) and Fe(III) complexes were determined potentiometrically in 1:1(v/v) ethanol-water mixture at an ionic strength of 0.5 mol.L-1 KCl and at 25.0 +/- 0.1 degrees C. The antifungal, antimicrobial activities and the minimum inhibitory concentration (MIC) values of the compounds were evaluated against Escherichia coli (0157:H7), Micrococcus luteus (NRRLB 4975), Bacillus cereus (RSKK 863) and Candida albicans (ATCC 16231).