Synthesis And Biological Studies Of A Tripodal Schiff Base Derived From 1,3,5-Tribromomethylbenzene And Its Trinuclear Ce(IV) and Nd(III) Salen Capped Complexes

Abstract

A tripodal Schiff base ligand, 1,3,5-tris(4-(4-carboxyphenyliminomethyl) phenoxy methyl) benzene (TT) was synthesized in a two-step reaction involving 1, 3, 5-tribromomethylbenzene. The ligand was used to synthesize Ce(IV) and Nd(III) salen capped complexes. These compounds 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 the Ce(IV)and Nd(III) ions through the oxygen atoms of the carboxylic group. The trinuclear Ce(IV) and Nd(III) salen capped complexes were characterized as being bridged by carboxylate anions to the Ce(IV)and 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 complexes 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. In vitro antimicrobial test indicate that [{Nd(OH)₂(salen)}₃(TT)].3H₂O is more potent against the test microorganisms relative to TT and [{Ce(OH)₂(salen)}₃(TT)].3H₂O.