title: Synthesis, characterization, antioxidant activity, and DNA-binding studies of 1-cyclohexyl-3-tosylurea and its Nd(III), Eu(III) complexes.
abstract: A new ligand, 1-cyclohexyl-3-tosylurea (H(2)L), was prepared by condensation ethyl N-(3-tossulfonyl) carbamate and cyclohexanamine. Its two lanthanide(III) complexes, Ln(H(2)L)(3) . 3NO(3) [Ln=Nd (1), and Eu (2)], have been synthesized and characterized on the base of element analyses, ESI-MS, molar conductivities, IR spectra and thermogravimetry/differential thermal analysis (TG-DTA). In addition, the DNA-binding properties of the ligand and its complexes have been investigated by electronic absorption spectroscopy, fluorescence spectroscopy, circular dichroic (CD) spectroscopy and viscosity measurements. The experiment results suggest that the ligand and its two complexes bind to DNA via a groove binding mode, and the binding affinity of the complex 2 is higher than that of the complex 1 and the ligand. Furthermore, the antioxidant activity (superoxide and hydroxyl radical) of the ligand and its metal complexes was determined by using spectrophotometer methods in vitro. These complexes were found to possess potent antioxidant activity and be better than standard antioxidants like vitamin C and mannitol. In particular, complex 2 displayed excellent activity on the superoxide and hydroxyl radical.
authors: State Key Laboratory of Applied Organic Chemistry and College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, PR China.
authors: Pin-Xian
authors: PX
authors: Xi
authors: Zhi-Hong
authors: ZH
authors: Xu
authors: Xiao-Hui
authors: XH
authors: Liu
authors: Feng-Juan
authors: FJ
authors: Chen
authors: Liang
authors: L
authors: Huang
authors: Zheng-Zhi
authors: ZZ
authors: Zeng
mesh_terms: D000975:Antioxidants / Q000138:chemical synthesis* / Q000494:pharmacology*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D002942:Circular Dichroism; D004247:DNA / Q000737:chemistry* / Q000187:drug effects*; D004055:Differential Thermal Analysis; D004121:Dimethyl Sulfoxide; D005063:Europium / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry; D017665:Hydroxyl Radical / Q000737:chemistry; D008024:Ligands; D009682:Magnetic Resonance Spectroscopy; D009556:Niobium / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013056:Spectrophotometry, Ultraviolet; D013481:Superoxides / Q000737:chemistry; D014508:Urea / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D014783:Viscosity
chemical_list: C529360:1-cyclohexyl-3-tosylurea; D000975:Antioxidants; D016166:Free Radical Scavengers; D008024:Ligands; D009556:Niobium; D013481:Superoxides; D017665:Hydroxyl Radical; D005063:Europium; D014508:Urea; D004247:DNA; D004121:Dimethyl Sulfoxide