Spectrochim Acta A Mol Biomol Spectrosc
October 2011
Two novel copper(II) thiocyanate complexes with 4-(N,N-dimethylamino) pyridine and N,N-dimethylformamide (1) and with 4-(N,N-dimethylamino) pyridine (2) have been synthesized and characterized. The crystal and molecular structures of complexes 1 and 2 were determined by single-crystal X-ray diffraction. Antioxidative activity tests in vitro showed that complex 1 has significant antioxidative activity against hydroxyl free radicals from the Fenton reaction and also oxygen free radicals, which is better than standard antioxidants like vitamin C and mannitol.
View Article and Find Full Text PDFThe interaction between bovine serum albumin (BSA) and the cobalt(II) complex with salicylaldehyde-2-phenylquinoline-4-carboylhydrazone (Co-SPC) was investigated using fluorescence spectroscopy, UV absorption, and circular dichroism (CD) under simulated physiologic conditions for the first time. Fluorescence data and UV absorption spectra revealed that the intrinsic fluorescence of BSA was strongly quenched by Co-SPC in terms of a static quenching process at a lower concentration of the complex and a combined quenching process at a higher concentration of the complex. Binding constants and binding sites were evaluated.
View Article and Find Full Text PDFThe synthesis and spectral properties of a chemidosimeter 1,4-di[2-(6-ethylamino-3-ethylimino-2,7-dimethyl-3H-xanthen-9-yl) benzoic acid (aminomethyl)-3-phenylthiourea] benzene (1) for Hg(II) ions are reported, and it has been demonstrated that 1 can be used as a fluorescent probe for monitoring Hg(II) ions in living cells.
View Article and Find Full Text PDFThe interaction of 1-phenyl-3-(coumarin-6-yl)sulfonylurea (SU22) with bovine serum albumin (BSA) has been investigated by fluorescence quenching spectroscopy combined with UV-absorption, circular dichroism (CD), Fourier transform infrared (FT-IR) spectroscopy techniques under simulative physiological conditions for the first time. Fluorescence data and UV-absorption spectra revealed that the quenching mechanism of fluorescence of BSA by SU22 was a static quenching process and the number of binding sites was about 0.8858; the thermodynamic parameters (DeltaG=-29.
View Article and Find Full Text PDF1-(4-aminoantipyrine)-3-tosylurea (H2L) and its three lanthanide (III) complexes, M(H2L)3 3NO3 [where M=Nd(III), Sm(III) and Eu(III)], have been synthesized and characterized. In addition, the DNA-binding properties of the three complexes have been investigated by UV-vis (ultraviolet and visible) absorption spectroscopy, fluorescence spectroscopy, circular dichroism (CD) spectroscopy, cyclic voltammetry, and viscosity measurements. Results suggest that the three complexes bind to DNA via a groove binding mode.
View Article and Find Full Text PDFA 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).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
November 2008
1-Cyclohexyl-3-tosylurea (HL) and its two complexes, ML2.2H2O [M=Ni(1), and Cd(2)], have been synthesized and characterized on the basis of elemental analyses, molar conductivities, IR spectra and thermal analyses. In addition, the DNA-binding properties of the ligand and the two complexes have been investigated by electronic absorption, fluorescence, CD spectroscopy and viscosity measurements.
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