Transition metal complexes of novel Schiff base

Abstract

New metal(II)/(III) complexes with novel Schiff base, resulted from the condensation of propane-1,3-diamine with bisaldehyde, as tetradentate ligand have been synthesized and characterized using elemental analyses, spectra (IR, 1H NMR and ESR), molar conductance, magnetic moment, and thermal studies. The IR data suggest the coordination mode for the Schiff base ligand which behaves as a tetradentate with the metal ions. Based on the elemental analysis, magnetic studies, electronic, and ESR data, octahedral geometry was proposed for the complexes. The ESR spectra of the Cu(II) complex in powdered form showed an axial symmetry with 2B1g as ground state and hyperfine structure. The thermal stability and degradation of the Schiff base ligand and its metal complexes were studied by TG. The molar conductance in DMF solution indicates that all complexes are electrolytes. The free Schiff base ligand and its metal complexes were tested for their in vitro antimicrobial activity against gram-positive and gram-negative organisms. The results showed that the synthesized complexes exhibited higher antimicrobial activity than their free Schiff base ligand. Of all the studied complexes, the Cu(II) and Co(II) complexes exhibited high antimicrobial activity at low micromolar inhibitory concentrations compared to the other complexes, amikacin standard, and the free Schiff base ligand.