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The Fight against the Influenza A Virus H1N1: Synthesis,Molecular Modeling,and Biological Evaluation of Benzofurazan Derivatives as Viral RNA Polymerase Inhibitors 下载免费PDF全文
Dr. Mafalda Pagano Dr. Daniele Castagnolo Dr. Martina Bernardini Anna Lucia Fallacara Ilaria Laurenzana Davide Deodato Dr. Ulrich Kessler Dr. Beatrice Pilger Dr. Lilli Stergiou Dr. Stephan Strunze Dr. Cristina Tintori Prof. Maurizio Botta 《ChemMedChem》2014,9(1):129-150
The influenza RNA polymerase complex, which consists of the three subunits PA, PB1, and PB2, is a promising target for the development of new antiviral drugs. A large library of benzofurazan compounds was synthesized and assayed against influenza virus A/WSN/33 (H1N1). Most of the new derivatives were found to act by inhibiting the viral RNA polymerase complex through disruption of the complex formed between subunits PA and PB1. Docking studies were also performed to elucidate the binding mode of benzofurazans within the PB1 binding site in PA and to identify amino acids involved in their mechanism of action. The predicted binding pose is fully consistent with the biological data and lays the foundation for the rational development of more effective PA–PB1 inhibitors. 相似文献
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Ilaria Cristofolini Alberto Molinari Giovanni Straffelini Palloma Vieira Muterlle 《Materials & Design》2011
Aim of this work is proposing a systematic design approach for wear resistant components produced by Powder Metallurgy (PM). Wear is a cause of failure for many industrial PM parts. Gears and cams, for example, are subjected to rolling and rolling–sliding wear, dry or lubricated depending on the applications. The design criteria are mostly empirical, thus resulting fully conservative, sometimes excessively conservative. A need for defining design criteria for wear resistant PM parts is thus revealed, to exploit at best the specific characteristics of both technology and materials. 相似文献
65.
Fortunati E Latterini L Rinaldi S Kenny JM Armentano I 《Journal of materials science. Materials in medicine》2011,22(12):2735-2744
New nanocomposite films based on a biodegradable poly (DL-Lactide-co-Glycolide) copolymer (PLGA) and different concentration
of silver nanoparticles (Ag) were developed by solvent casting. In vitro degradation studies of PLGA/Ag nanocomposites were
conducted under physiological conditions, over a 5 week period, and compared to the behaviour of the neat polymer. Furthermore
the silver ions (Ag+) release upon degradation was monitored to obtain information on the properties of the nanocomposites during the incubation.
The obtained results suggest that the PLGA film morphology can be modified introducing a small percentage of silver nanoparticles
that do not affect the degradation mechanism of PLGA polymer in the nanocomposite. However results clearly evinced the stabilizing
effect of the Ag nanoparticles in the PLGA polymer and the mineralization process induced by the combined effect of silver
and nanocomposite surface topography. The Ag+ release can be controlled by the polymer degradation processes, evidencing a prolonged antibacterial effect. 相似文献
66.
Kotoni D Ciogli A Molinaro C D'Acquarica I Kocergin J Szczerba T Ritchie H Villani C Gasparrini F 《Analytical chemistry》2012,84(15):6805-6813
A new chiral stationary phase for ultrahigh-pressure liquid chromatography (UHPLC) applications was prepared by covalent attachment of the Whelk-O1 selector to spherical, high-surface-area 1.7-μm porous silica particles. Columns of varying dimensions (lengths of 50, 75, 100, and 150 mm and internal diameters of 3.0 or 4.6 mm) were packed and characterized in terms of permeability, efficiency, retention, and enantioselectivity, using both organic and water-rich mobile phases. A conventional HPLC Whelk-O1 column based on 5.0-μm porous silica particles and packed in a 250 mm × 4.6 mm column was used as a reference. Van Deemter curves, generated with low-molecular-weight solutes on a 100 mm × 4.6 mm column packed with the 1.7-μm particles, showed H(min) (μm) and μ(opt) (mm/s) values of 4.10 and 5.22 under normal-phase and 3.74 and 4.34 under reversed-phase elution conditions. The flat C term of the van Deemter curves observed with the 1.7-μm particles allowed the use of higher-than-optimal flow rates without significant efficiency loss. Kinetic plots constructed from van Deemter data confirmed the ability of the column packed with the 1.7-μm particles to afford subminute separations with good efficiency and its superior performances in the high-speed regime, compared to the column packed with 5.0-μm particles. Resolutions in the time scale of seconds were obtained using a 50-mm-long column in the normal phase or polar organic mode. The intrinsic kinetic performances of 1.7-μm silica particles are retained in the Whelk-O1 chiral stationary phase, clearly demonstrating the potentials of enantioselective UHPLC in terms of high speed, throughput, and resolution. 相似文献
67.
Rosso Ilaria Antonini Massimiliano Galletti Camilla Saracco Guido Specchia Vito 《Topics in Catalysis》2004,30(1-4):475-480
Topics in Catalysis - Ru-based catalysts supported on A zeolites and alumina were synthesised, characterised (XRD, SEM-EDS, TPR) and tested under realistic conditions for the preferential oxidation... 相似文献
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Sulfolobus solfataricus protein disulphide oxidoreductase: insight into the roles of its redox sites
Limauro D Saviano M Galdi I Rossi M Bartolucci S Pedone E 《Protein engineering, design & selection : PEDS》2009,22(1):19-26
Sulfolobus solfataricus protein disulphide oxidoreductase (SsPDO)contains three disulphide bridges linking residues C41XXC44,C155XXC158, C173XXXXC178. To get information on the role playedby these cross-links in determining the structural and functionalproperties of the protein, we performed site-directed mutagenesison Cys residues and investigated the changes in folding, stabilityand functional features of the mutants and analysed the resultswith computational analysis. The reductase activity of SsPDOand its mutants was evaluated by insulin and thioredoxin reductaseassays also coupled with peroxiredoxin Bcp1 of S. solfataricus.The three-dimensional model of SsPDO was constructed and correlatedwith circular dichroism data and functional results. Biochemicalanalysis indicated a key function for the redox site constitutedby Cys155 and Cys158. To discriminate between the role of thetwo cysteine residues, each cysteine was mutagenised and thebehaviour of the single mutants was investigated elucidatingthe basis of the electron-shuffling mechanism for SsPDO. Finally,cysteine pK values were calculated and the accessible surfacefor the cysteine side chains in the reduced form was measured,showing higher reactivity and solvent exposure for Cys155. 相似文献