Synthesis, Characterization, and Antimicrobial Activity Studies of New Schiff Base Tetradentate Ligands and Their Manganese (II) Complexes

Two Schiff base tetradentate ligands 4 and 5 were synthesized by condensation reactions of 4-hydroxy-3-methoxy-5-((2-nitrophenyl)diazenyl) benzaldehyde 1 with 1,2-diaminoethane 2 and 1,2-diaminobenzene 3, respectively. Treatment of synthesized ligands with the manganese (II) chloride MnCl2 6 gave two complexes 7 and 8 of general formula ML. The synthesized ligands and their complexes were characterized by FTIR, UV-Vis, Mass spectroscopy, and elemental analysis. The biological activity of the synthesized compounds were tested. It was found that ligand 5 and the complexes 7 and 8 possess antibacterial activity against the gram –ve Proteus mirabilis.