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991.
Ohne Zusammenfassung 相似文献
992.
Coralie Assailly Clarisse Bridot Dr. Amélie Saumonneau Paul Lottin Dr. Benoit Roubinet Dr. Eva-Maria Krammer Francesca François Federica Vena Dr. Ludovic Landemarre Dr. Dimitri Alvarez Dorta Dr. David Deniaud Dr. Cyrille Grandjean Dr. Charles Tellier Dr. Sagrario Pascual Dr. Véronique Montembault Dr. Laurent Fontaine Dr. Franck Daligault Dr. Julie Bouckaert Dr. Sébastien G. Gouin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(9):3142-3150
Bacterial sialidases (SA) are validated drug targets expressed by common human pathogens such as Streptococcus pneumoniae, Vibrio cholerae, or Clostridium perfringens. Noncovalent inhibitors of bacterial SA capable of reaching the submicromolar level are rarely reported. In this work, multi- and polyvalent compounds are developed, based on the transition-state analogue 2-deoxy-2,3-didehydro-N-acetylneuraminic (DANA). Poly-DANA inhibits the catalytic activity of SA from S. pneumoniae (NanA) and the symbiotic microorganism B. thetaiotaomicron (BtSA) at the picomolar and low nanomolar levels (expressed in moles of molecules and of DANA, respectively). Each DANA grafted to the polymer surpasses the inhibitory potential of the monovalent analogue by more than four orders of magnitude, which represents the highest multivalent effect reported so far for an enzyme inhibition. The synergistic interaction is shown to operate exclusively in the catalytic domain, and not in the flanked carbohydrate-binding module (CBM). These results offer interesting perspectives for the multivalent inhibition of other SA families lacking a CBM, such as viral, parasitic, or human SA. 相似文献
993.
Zohra Benfodda Franck Guillen Hlne Arnion Abdelkader Dahmani Hubert Blancou 《Heteroatom Chemistry》2009,20(6):355-361
This study describes a new and advantageous procedure for the synthesis of alkanesulfonyl chlorides ( 2 ) by the reaction of alkyl thiocyanates ( 1 ) with sulfuryl chloride in a mixture of acetic acid and water. The alkanesulfonyl chlorides were obtained in good yields. © 2009 Wiley Periodicals, Inc. Heteroatom Chem 20:355–361, 2009; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20559 相似文献
994.
Dr. Olivier Galangau Dr. Elsa Caytan William T. Gallonde Dr. Isabelle de Waele Dr. Franck Camerel Prof. Stéphane Rigaut 《欧洲无机化学杂志》2023,26(1):e202200579
In this work, we report our latest results regarding the self-assembly properties of two Ru-acetylides complexes and their corresponding free organic ligands, in solution and in the solid state. The four compounds show mesogenic properties, which we have rationalized thanks to extensive DSC, SAXS, POM, FTIR and molecular dynamic investigations. We clearly establish that hydrogen bonds stabilize the supramolecular structures, and that introducing the metal center and its coordination sphere induces large change in the liquid crystal properties. In addition, for the monoacetylide compound Ru2 , solution-state studies helped us rationalize its supramolecular abilities. In particular, we demonstrate that Ru2 follows an isodesmic growth supramolecular polymerization in aromatic solvent. 相似文献
995.
996.
Franck Schillinger Uwe Hahn Sebastiano Guerra Thi Minh Nguyet Trinh David Sigwalt Michel Holler Iwona Nierengarten Jean-François Nierengarten 《Helvetica chimica acta》2023,106(6):e202300026
Bis- and tris-malonates constructed around a silicon atom have been prepared by reaction of malonate derivatives bearing an alcohol function with di-tert-butylsilyl bis(trifluoromethanesulfonate) and tert-butyl(trichloro)silane, respectively. These compounds have been used for the regioselective bis- and tris-functionalization of C60 under Bingel conditions. By changing the nature of the linker between the central Si atom and the reactive malonate groups, the malonate precursors have been optimized to produce specific bis- and tris-adducts with excellent regioselectivity. A complete understanding of the electronic and stereochemical factors governing the regioselectivity has been obtained by combining computational studies with a complete analysis of the by-products formed during the reactions of the Si-tethered tris-malonates with C60. Finally, desilylation reactions of the resulting fullerene bis- and tris-adducts have been carried out to generate the corresponding acyclic fullerene bis- and tris-adducts bearing alcohol functions. 相似文献
997.
Rita Raachini Dr. Ferdaous Ben Romdhane Dr. Capucine Sassoye Prof. Maya Boutros Prof. Franck Launay 《ChemCatChem》2024,16(2):e202300948
This paper focuses on the hydrogenolysis of 2-phenoxy-1-phenylethanone, modelling a pre-oxidized form of lignin using five catalysts of similar metal content, prepared by impregnation of Ni(II), Rh(III) and both metals onto Aerosil-380 in the presence of NH3, followed by a reduction step. The materials were characterized in the dried as-synthesized state and after consecutive reductive and oxidative treatments, showing the great dispersion of the metal (oxide nanoparticles with sizes<2 nm). Working with 1 mol % of the reduced metal (500 °C) per substrate at 180 °C with isopropanol as H-donor, the most active catalyst, but also the least selective towards phenol, was initially found to be the Ni-based one. Under similar conditions, the lower capacity of the Rh-based catalyst to induce H transfer from isopropanol favoured phenol formation but resulted in much slower C−OAr cleavage. Despite a very high dispersion of the two metals in the bimetallic catalysts, no synergy was found, suggesting that Ni would be segregated at the surface. Finally, the best phenol productivity could be reached by reducing the Ni-based catalyst at 650 °C, which led to a more efficient cleavage of C−OAr bonds. In this way, it was possible to produce 8 times more phenol per hour. 相似文献