title: Syntheses, characterization, biological activities and photophysical properties of lanthanides complexes with a tetradentate Schiff base ligand.
abstract: A tetradentate Schiff base ligand L (N,N'-bis(1-naphthaldimine)-o-phenylenediamine) was prepared from the condensation of 2-hydroxy-1-naphthaldehyde with o-phenylenediamine in a molar ratio of 2:1. New eight lanthanide metal complexes [LnL(NO(3))(2)(H(2)O)(x)](NO(3)) {Ln(III) = Nd, Dy, Sm, Pr, Gd, Tb, La and Er, x = 0 for Nd, Sm, 1 for La, Gd, Pr, Nd, Dy, and 2 for Tb} were prepared. The characterization and nature of bonding of these complexes were elucidated by elemental analysis, spectral analysis ((1)H NMR, FT-IR, UV-vis), molar conductivity measurements, luminescence spectra and thermogravimetric studies. Analytical and spectral data revealed that the ligand L coordinates to the central Ln(III) ions by its two imine nitrogen atoms and two phenolic oxygen atoms with 1:1 stoichiometry. Under the excitation with 329 nm at room temperature, Tb and Dy complexes exhibited characteristic luminescence of the central metal ions attributed to efficient energy transfer from the ligand to the metal center. Most of Ln(III) complexes found to exhibit antibacterial activities against a number of pathogenic bacteria. We found that the antioxident activity of Ln(III) complexes on DPPH(•) is concentration dependent and higher than that of the free ligand L.
authors.affiliation: Department of Applied Chemical Sciences, Jordan University of Science and Technology, Irbid 22110, Jordan. tahaz33@just.edu.jo
authors.forename: Ziyad A
authors.initials: ZA
authors.lastname: Taha
authors.forename: Abdulaziz M
authors.initials: AM
authors.lastname: Ajlouni
authors.forename: Waleed
authors.initials: W
authors.lastname: Al Momani
authors.forename: Abeer A
authors.initials: AA
authors.lastname: Al-Ghzawi
mesh_terms: D000890:Anti-Infective Agents / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D056831:Coordination Complexes / Q000138:chemical synthesis* / Q000737:chemistry* / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D007097:Imines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D028581:Lanthanoid Series Elements / Q000737:chemistry* / Q000494:pharmacology; D008024:Ligands; D008826:Microbial Sensitivity Tests; D008954:Models, Biological; D009281:Naphthalenes / Q000737:chemistry; D010655:Phenylenediamines / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D055668:Photochemical Processes; D012545:Schiff Bases / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000890:Anti-Infective Agents; D056831:Coordination Complexes; D016166:Free Radical Scavengers; D007097:Imines; D028581:Lanthanoid Series Elements; D008024:Ligands; C569551:N,N'-bis(1-naphthaldimine)-o-phenylenediamine; D009281:Naphthalenes; D010655:Phenylenediamines; D012545:Schiff Bases; C062247:2-hydroxy-1-naphthaldehyde; C034193:1,2-diaminobenzene