Synthesis, Characterization, Antioxidant Activity, and DNA-Binding Studies of 1-Cyclohexyl-3-tosylurea and Its Nd(III), Eu(III) Complexes

• Published in: Chemical & Pharmaceutical Bulletin Vol. 56; no. 4; pp. 541 - 546
• Main Authors: Xi, Pin-Xian, Xu, Zhi-Hong, Liu, Xiao-Hui, Chen, Feng-Juan, Huang, Liang, Zeng, Zheng-Zhi
• Format: Journal Article
• Language: English
• Published: TOKYO The Pharmaceutical Society of Japan 01.04.2008; Pharmaceutical Society of Japan; Pharmaceutical Soc Japan; Japan Science and Technology Agency
• Subjects: 1-cyclohexyl-3-tosylurea; antioxidant activity; Antioxidants - chemical synthesis; Antioxidants - pharmacology; Chemical Phenomena; Chemistry; Chemistry, Medicinal; Chemistry, Multidisciplinary; Chemistry, Physical; Circular Dichroism; Differential Thermal Analysis; Dimethyl Sulfoxide; DNA - chemistry; DNA - drug effects; Europium - chemistry; Free Radical Scavengers - chemistry; groove binding; Hydroxyl Radical - chemistry; Life Sciences & Biomedicine; Ligands; Magnetic Resonance Spectroscopy; Niobium - chemistry; Pharmacology & Pharmacy; Physical Sciences; rare earth complex; Science & Technology; Spectrometry, Fluorescence; Spectrometry, Mass, Fast Atom Bombardment; Spectrophotometry, Infrared; Spectrophotometry, Ultraviolet; Superoxides - chemistry; Urea - analogs & derivatives; Urea - chemical synthesis; Urea - pharmacology; Viscosity; rare earth complex; DEOXYRIBONUCLEIC-ACID; LIGANDS; CRYSTAL; AGENTS; CLEAVAGE; 1-cyclohexyl-3-tosylurea; antioxidant activity; NI(II); groove binding
• ISSN: 0009-2363; 1347-5223
• DOI: 10.1248/cpb.56.541

A new ligand, 1-cyclohexyl-3-tosylurea (H2L), was prepared by condensation ethyl N-(3-tossulfonyl) carbamate and cyclohexanamine. Its two lanthanide(III) complexes, Ln(H2L)3·3NO3 [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.