A series of artificial receptors, based on a sulfonamido system, have been designed and synthesized. The interaction of these receptors with biologically important anions was determined by UV-vis, (1)H NMR titration and electrochemical experiments. Results indicate that these receptors show high recognition abilities for fluoride (F(-)) or acetate (AcO(-)), moderate affinities for dihydrogen phosphate (H(2)PO(4)(-)) or hydroxyl (OH(-)) and almost no affinities for chloride (Cl(-)), bromide (Br(-)) or iodide (I(-)).
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
March 2009
A new and simple colorimetric sensor with high selectivity for acetate ion based on 1,10-phenanthroline-2,9-dicarboxyaldehyde-di-(p-substitutedphenylhydrazone) receptor 2 has been synthesized. The selectively binding ability of receptor 2 to acetate ion over other anions tested was demonstrated by UV-vis absorption spectroscopy in DMSO. Comparing with other anions studied, the UV-vis absorption spectrum in dimethyl sulfoxide shows significant response toward acetate ion with high selectivity, and meanwhile dramatic color change is observed from yellow to green in the presence of acetate ion (5 x 10(-6)mol/L).
View Article and Find Full Text PDFAn efficient colorimetric sensor with a thiourea moiety as binding sites and p-nitrophenylhydrazine as a signaling unit has been synthesized by only one single-step procedure. Selectivity for anions with the distinct geometry (tetrahedral, trigonal planar and spherical) has been investigated in dry DMSO and even in DMSO/H(2)O (95:5, v/v) solutions through the naked-eye experiment, UV-vis titration and (1)H NMR titration techniques. In particular, the fluoride of toothpaste can be detected qualitatively by the sensor 1.
View Article and Find Full Text PDFA novel phenylhydrazone-based indole anion receptor is synthesized by a simple method, and the receptor binds acetate anions with good selectivity in DMSO solution, which is related to the structure of the receptor matching with the anion. The binding properties of the host are examined by UV-vis changes. The color changes of the host upon the addition of a variety of structurally different anions were also utilized as nake-eyed recognization (from orange to purple, first figure), The hydrogen bonds between recognization sites (phenylhydrazone and indole N-H) and anions were determined on the basis of (1)H NMR experiments.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
August 2008
A novel and neutral anion sensor bearing a urea group as binding sites and 2,4-di nitrophenylhydrazine unit as a molecular architecture and a chromophore was synthesized and the visible color changes, the UV-vis and (1)H NMR spectral responses toward anions were assessed.
View Article and Find Full Text PDFTwo novel artificial receptors based on diamide and bearing phenol group and copper(II) have been synthesized. Their anion-binding properties are evaluated for F(-), Cl(-), Br(-), I(-), AcO(-), H(2)PO(4)(-) and OH(-) by UV-vis and (1)H NMR titration experiments to further elucidate the impact of phenol group and copper(II) on the chemistry of anion-recognition. Results indicate that the interacted model of fluoride anion with receptor 1 is different from other anions and the (1)H NMR signals of receptor 2 occur changes after the addition of fluoride anion.
View Article and Find Full Text PDFA novel artificial receptor, (3'-nitrobenzo)[2,3-d]-(3''-nitrobenzo)[9,10-d]-1,4,8,11-tetraazacyclotetradecane-5,7,12,14-tetraone, was designed and synthesized. The interactions of this receptor with different anions were determined by UV-vis and (1)H NMR titration experiments, and their affinity constants to different anions were compared with those of other similar/different systems. The results indicated that this receptor showed a high selective and recognitive ability for F(-) among F(-), Cl(-), Br(-), I(-), AcO(-), OH(-), and H(2)PO(4)(-).
View Article and Find Full Text PDFTwo novel lanthanum(III) complexes containing 2-methylene-1,10-phenanthroline units bridged by aliphatic diamines were synthesized and characterized by elemental analysis, IR, NMR, thermal analysis and conductance measurements. They have been assayed for anticancer activity in vitro against HL-60 (human leukocytoma) cells, PC-3MIE8 (human prostate carcinoma) cells, BGC-823 (human stomach carcinoma) cells, MDA-MB-435 (human galactophore carcinoma) cells, Bel-7402 (human liver carcinoma) cells, and Hela (human cervix carcinoma) cells. The results show that the two complexes exhibit good cytotoxic activities against different cell lines in general, especially more effective than cisplatin against Bel-7402, BGC-823 and MDA-MB-435 cell lines.
View Article and Find Full Text PDFTwo inhibitor-containing 'half-sandwich' cobalt(II) complexes [(TpPh)Co(X)(CH3OH)m] x nCH3OH ((TpPh) = hydrotris (3-phenylpyrazolyl)borate; 1: X- = N3-, m = 1, n = 2; 2: X- = NCS-, m = 0, n = 0) have been synthesized and used as the catalysts in the bicarbonate dehydration reaction. The structures of 1 and 2 were determined by X-ray diffraction analysis, which shows that N3- and NCS- coordinate to the Co(II) ions of 1 and 2, respectively, with the Co-N bond lengths of 1.992(6) A and 1.
View Article and Find Full Text PDFThe phenanthroline bridging polyaza ligands L1, L2 and L3 can selectively and strongly bind nucleotides at physiological pH, and hence accelerate the hydrolysis rate of the bound ATP. It is interesting that a phosphoramidate intermediate at 2.88 ppm (should be added 5.
View Article and Find Full Text PDFA series of half-sandwich copper(II) complexes [TpPh]CuX ([TpPh] = hydrotris(3-phenyl-pyrazolyl)borate; X- = OH- (1), N3- (2), NCS- (3)) have been synthesized as models for carbonic anhydrase. The structure of 3 was determined by X-ray diffraction analysis. Crystals of 3 (C37H30BCuN9S) are triclinic, space group P1 with a = 11.
View Article and Find Full Text PDFThe interaction of the lanthanum(III) La(III)-L (L=N,N'-bis-(1-carboxy-2-methylpropyl)-1,10-phenanthroline-2,9-dimethanamine) complex with calf thymus DNA was studied by electronic spectra, fluorescence spectra and circular dichroic spectra. The La(III)-L complex was assayed for antitumor activity in vitro against the HL-60 (the human leucocytoma) cells, HCT-8 (the human coloadenocarcinoma) cells, BGC-823 (the human carcinoma of stomach) cells, Bel-7402 (the human liver carcinoma) cells and KB (the human nasopharyngeal carcinoma) cells. The results show that the La(III)-L complex has activity against HL-60 cells, Bel-7402 cells and KB cells.
View Article and Find Full Text PDF