Synthesis, Characterization and Biological Studies of Trinuclear Nd(III) Salen Capped Complex with 2,4,6-tris(4-carboxybenzimino)-1,3,5-triazine

摘要

A novel trinuclear Nd(III) salen capped complex of 2,4,6-tris(4-carboxybenzimino)-1,3,5-triazine was synthesized for the first time by the reaction of Nd(III) ligand complex with 2,4,6-tris(4- carboxybenzimino)-1,3,5-triazine. The ligand and complex were characterized using UV-Visible, IR, 1H and 13C NMR spectroscopies, elemental analysis, and molar conductivity measurements. The spectral studies indicate that the ligand is hexadentate and coordinates to Nd(III) ions through the oxygen atoms of the carboxylic group. The trinuclear Nd(III) salen capped complex was characterized as being bridged by carboxylate anions to the Nd(III) salen centers and displays a coordination number of eight by involving two hydroxyl groups in the coordination sphere. The in vitro antimicrobial activities of the ligand and its Nd(III) salen capped complex were investigated against Gram-negative bacteria: Escherichia coli (ATCC 6749) and Pseudomonas aeruginosa (ATCC 9027), Gram-positive bacteria: Staphylococcus aureus (ATCC 6538P) and Bacillus cereus (ATCC 14579), and fungi: Candida albicans and Aspergillus niger by the agar well diffusion technique. The ligand was found to be more potent against the test microorganisms relative to the trinuclear Nd(III) salen capped complex. The trinuclear Nd(III) salen capped complex inhibits the growth of Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, and Aspergillus niger at concentrations of 50 μg/mL.