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301.
Tintori C Manetti F Veljkovic N Perovic V Vercammen J Hayes S Massa S Witvrouw M Debyser Z Veljkovic V Botta M 《Journal of chemical information and modeling》2007,47(4):1536-1544
HIV-1 integrase (IN) is an essential enzyme for viral replication and represents an intriguing target for the development of new drugs. Although a large number of compounds have been reported to inhibit IN in biochemical assays, no drug active against this enzyme has been approved by the FDA so far. In this study, we report, for the first time, the use of the electron-ion interaction potential (EIIP) technique in combination with molecular modeling approaches for the identification of new IN inhibitors. An innovative virtual screening approach, based on the determination of both short- and long-range interactions between interacting molecules, was employed with the aim of identifying molecules able to inhibit the binding of IN to viral DNA. Moreover, results from a database screening on the commercial Asinex Gold Collection led to the selection of several compounds. One of them showed a significant inhibitory potency toward IN in the overall integration assay. Biological investigations also showed, in agreement with modeling studies, that these compounds prevent recognition of DNA by IN in a fluorescence fluctuation assay, probably by interacting with the DNA binding domain of IN. 相似文献
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303.
Anter J de Abreu-Abreu N Fernández-Bedmar Z Villatoro-Pulido M Alonso-Moraga A Muñoz-Serrano A 《Natural product communications》2011,6(1):59-64
Vitis vinifera is a widespread crop all over the world. The biophenols present in grapes have a remarkable influence on wine quality and also confer potential health-protecting properties to this fruit. The aim of the present work was to assess the beneficial properties of skin, seeds and pulp of red table grapes (RTG) (Vitis vinifera, Palieri Cadiz variety). Two potential beneficial activities of red table grapes (RTG) were analyzed: (i) The maintenance of genomic stability studying their genotoxic/antigenotoxic effects, and (ii) the in vitro cytotoxic effect against tumor cells of RTG components. The genotoxic and/or antigenotoxic effect was measured applying the somatic mutation and recombination test on wing imaginal discs of Drosophila melanogaster. The cytotoxic effect was monitored using the HL60 human leukemia model to evaluate the antiproliferative potential of the different parts of RTG. The three major parts (skin, seeds and pulp) are not genotoxic. When antigenotoxicity assays were performed using hydrogen peroxide as the oxidative genotoxin, skin, seed and pulp exerted a desmutagenic effect, with seeds and skin showing the most potent effect. The cytotoxicity tests using HL60 cells indicated that only skin and pulp fractions are able to inhibit the tumor growth, with skin having the lowest IC50 (1.8 mg/mL versus 8 mg/mL of pulp). These results suggest that RTG are potent anti-mutagens that protect DNA from oxidative damage as well as being cytotoxic toward the HL60 tumor cell line. 相似文献
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306.
Bonose-Crosnier de Bellaistre M Nowik W Tchapla A Heron S 《Journal of chromatography. A》2011,1218(6):778-786
Chromatographic study of natural products helps to determine their molecular composition and to identify their sources (biological, geographical, etc.). However, identifying anthraquinoids is still a challenge because this chemical family is composed of more than half a thousand molecules. In the present work, a series of C18 stationary phases were systematically studied to evaluate their separation potential for these compounds in high performance reversed phase liquid chromatography (RPLC). The stationary phases with various physicochemical properties were evaluated with respect to the separation of 30 standards. Selectivity of the studied stationary phases and symmetry of the obtained peaks were chosen as the evaluation criteria. Calculations of symmetry and separation capacity parameters have been proposed. These parameters are not dependent on the dimensions of the columns and were used for the classifications of phases. In conclusion, this study is intended to be a guide as to which stationary phases analysts can use for resolving separation of a complex mixture of anthraquinoids. 相似文献
307.
Mathilde LachiaSébastien Iriart Myriam BaalouchAlain De Mesmaeker Renaud Beaudegnies 《Tetrahedron letters》2011,52(25):3219-3222
We report here the use of the readily accessible ethyl-2-(2-chloroethyl)acrylate as a new very versatile α-cyclopropylester cation synthon, which reacts efficiently and selectively with carbon-, nitrogen-, sulfur- or phosphorus-centered nucleophiles through Michael addition followed by intramolecular capture of the incipient ester enolate to afford funtionalized cyclopropane esters in high yields. 相似文献
308.
Claire Joqueviel Robert Martino Veronique Gilard Myriam Malet-martino Ulf Niemeyer 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract 31P NMR was used to analyze urine from 4 patients treated with cyclophosphamide (CP) over 2 days. CP and most of its phosphorated metabolites (carboxyCP (CXCP), dechloroethylCP (DCCP), alcoCP, ketoCP and phosphoramide mustard (PM)) were assayed. Several other signals (10- 15) corresponding to unknown compounds were observed. Seven new compounds were identified: all were hydrolysis products of CP or its metabolites CXCP, DCCP and PM as reported below. 相似文献
309.
Jessica Barrientos Barria Alexandre Dobroc Hélène Coudert-Alteirac Myriam Raybaut Nicolas Cézard Jean-Baptiste Dherbecourt Thomas Schmid Basile Faure Grégoire Souhaité Jacques Pelon Jean-Michel Melkonian Antoine Godard Michel Lefebvre 《Applied physics. B, Lasers and optics》2014,117(1):509-518
We report on the remote sensing capability of an integrated path differential absorption lidar (IPDIAL) instrument, for multi-species gas detection and monitoring in the 3.3–3.7 µm range. This instrument is based on an optical parametric source composed of a master oscillator-power amplifier scheme—whose core building block is a nested cavity optical parametric oscillator—emitting up to 10 µJ at 3.3 µm. Optical pumping is realized with an innovative single-frequency, 2-kHz repetition rate, nanosecond microchip laser, amplified up to 200 µJ per pulse in a single-crystal fiber amplifier. Simultaneous monitoring of mean atmospheric water vapor and methane concentrations was performed over several days by use of a topographic target, and water vapor concentration measurements show good agreement compared with an in situ hygrometer measurement. Performances of the IPDIAL instrument are assessed in terms of concentration measurement uncertainties and maximum remote achievable range. 相似文献
310.
2-Amino-4-(2-hydroxynaphthyl)-4H-chromene-3-carbonitriles were synthesized by Michael addition of various 3-cyanoiminocoumarins and β-naphthol in good yield. The heterocyclization of these materials in an acidic medium leads new heterocyclic compounds, which have not previously been described, in moderate to good yields and good selectivity. The synthesized compounds were characterized by infrared, 1H NMR, 13C NMR, two-dimensional NMR, and elemental analysis. 相似文献