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排序方式: 共有2266条查询结果,搜索用时 15 毫秒
81.
Jacopo Sgrignani Filomena De Luca Hayarpi Torosyan Jean-Denis Docquier Da Duan Beatrice Novati Fabio Prati Giorgio Colombo Giovanni Grazioso 《Journal of computer-aided molecular design》2016,30(10):851-861
β-Lactamases are bacterial enzymes conferring resistance to β-lactam antibiotics in clinically-relevant pathogens, and represent relevant drug targets. Recently, the identification of new boronic acids (i.e. RPX7009) paved the way to the clinical application of these molecules as potential drugs. Here, we screened in silico a library of ~1400 boronic acids as potential AmpC β-lactamase inhibitors. Six of the most promising candidates were evaluated in biochemical assays leading to the identification of potent inhibitors of clinically-relevant β-lactamases like AmpC, KPC-2 and CTX-M-15. One of the selected compounds showed nanomolar K i value with the clinically-relevant KPC-2 carbapenemase, while another one exhibited broad spectrum inhibition, being also active on Enterobacter AmpC and the OXA-48 class D carbapenemase. 相似文献
82.
Jumpei Taguchi Takumi Takeuchi Rina Takahashi Fabio Masero Hajime Ito 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(22):7377-7381
Potassium acyltrifluoroborates (KATs) were prepared through copper(I)‐catalyzed borylation of aldehydes and subsequent oxidation. This synthetic route is characterized by the wide range of aldehydes accessible, favorable step economy, mild reaction conditions, and tolerance of various functional groups, and it enables the facile generation of a range of KATs, for example, bearing halide, sulfide, acetal, or ester moieties. Moreover, this method was applied to the three‐step synthesis of various α‐amino acid analogues that bear a KAT moiety on the C‐terminus by using naturally occurring amino acids as the starting material. 相似文献
83.
Ramachandra S Schuermann KC Edafe F Belser P Nijhuis CA Reus WF Whitesides GM De Cola L 《Inorganic chemistry》2011,50(5):1581-1591
Two luminescent ruthenium complexes containing tripod-type end groups linked through a rigid spacer to a phenanthroline derivative, able to confer an axial geometry to the complexes, are described. One of the compounds is functionalized with thioacetate groups in order to link the metal complex to metallic surfaces. The photophysical and electrochemical behavior of the complexes are studied in solution and on conductive substrates and, furthermore, self-assembled monolayers are investigated in a junction using gold and an indium gallium eutectic, as electrodes, and by time-resolved confocal microscopy. The results show that the complexes form very stable and well-ordered monolayers because of the tripod system, which can anchor the complex almost perpendicular to the surfaces. 相似文献
84.
Fabio D’Agostino Elvira Oliveri Emanuela Bagnato Francesca Falco Salvatore Mazzola Mario Sprovieri 《Analytica chimica acta》2014
The aim of this work was to develop a new method to determine the mercury (Hg) concentrations in phosphate rock using a dedicated analytical instrument (the DMA80 Tricell by Milestone) that employs an integrated sequence of thermal decomposition followed by catalyst conversion, amalgamation and atomic absorption spectrophotometry. However, this instrument underestimates Hg concentrations when phosphorite and apatite rocks are investigated with a classic thermal decomposition treatment that complies with US EPA method 7473. 相似文献
85.
Fabio BonaLuisella De Vitis Saverio FlorioLudovico Ronzini Luigino Troisi 《Tetrahedron》2003,59(9):1381-1387
2-Chloroalkylthiazolyllithiums, prepared by deprotonating the 2-chloroalkylthiazoles with n-BuLi at −78°C in THF, add to ketones or imines affording in ‘one-pot’ oxiranes and aziridines in a Z stereoselective manner. 相似文献
86.
Maurizio Canetti Santolo Taglialatela ScafatiAdriana Cacciamani Fabio Bertini 《Polymer Degradation and Stability》2012,97(1):81-87
Polypropylene has been compounded with a commercial organoclay both in the absence and in the presence of hydrogenated oligo(cyclopentadiene) (HOCP) as a compatibiliser. The characteristics and the properties of the nanocomposites were evaluated and compared. HOCP favours the intercalation of the polypropylene in the organoclay galleries and enables a more homogeneous dispersion of the nanoclay throughout the polymer matrix. In the compatibilised nanocomposite, the diluent effect ascribed to the HOCP component is associated with the nucleating action of the nanoclay, resulting in the development of the β-crystalline form of the polypropylene. The presence of HOCP preserves the molecular weight of the polymer during the processing and gives good overall mechanical properties to the compatibilised nanocomposite. The thermo-oxidative degradation of the polypropylene is strongly delayed in the compatibilised nanocomposite. 相似文献
87.
Fabio Rodrigues Gustavo M. do Nascimento Paulo S. Santos 《Macromolecular rapid communications》2007,28(5):666-669
Polyaniline is a model molecular system in the study of conductive polymers. Ionic liquids, on the other hand, are becoming more and more a very convenient alternative for conventional organic solvents. The dissolution of polyaniline‐emeraldine base (PANI‐EB) in imidazolium ILs leads to its doping, as indicated by optical and resonance Raman spectroscopies. In this study, it is proposed that the interaction of PANI‐EB and imidazolium ILs involves the specific interaction of the quinoid moiety of the former with the imidazolium ring of the latter, an interpretation that is also based on N K‐edge XANES measurements of neat PANI‐EB, neat ILs, and of their solutions.
88.
Ma. Carmen García-González Eduardo Hernández-Vázquez Fabio A. Vengochea-Gómez Luis D. Miranda 《Tetrahedron letters》2018,59(9):848-852
1,4- or 1,5-migration of a double bond of dehydroalanines under palladium catalysis is reported. The process occurred with several highly-substituted dehydroalanines under mild typical Heck reaction conditions. Although this was one of the first reports of a palladium-catalyzed 1,5-olefin migration, the outcome of the reaction was susceptible to the starting material. Mechanistically, the process involved a five- (1,4-migration) or six-membered ring (1,5-migration) organopalladium intermediate, which cleaved a C–N bond in an β-amino elimination process. 相似文献
89.
90.
A new approach for target quantitative analysis for comprehensive two-dimensional gas chromatography (GC × GC), interval Multi-way Partial Least Square (iNPLS) is presented and evaluated in this paper. In iNPLS, the two-dimensional chromatogram is split in small sections; each of these pieces is treated as an independent new chromatogram. Separated conventional NPLS calibration models for the concentration of the target analyte are built for each of the pieces of the whole chromatogram, and the best model is selected for quantitative analysis. An algorithm for iNPLS running on MatLab platform was written, preliminarily evaluated with using solutions of model compounds with different chemical properties and subsequently applied to quantify some allergens in perfume samples. The results were found to be adequate, and good precision and accuracy was obtained even for poorly resolved peaks. 相似文献