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排序方式: 共有1413条查询结果,搜索用时 468 毫秒
61.
62.
Dr. Jérémie Topin Claire A. de March Dr. Landry Charlier Prof. Dr. Catherine Ronin Prof. Dr. Serge Antonczak Dr. Jérôme Golebiowski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10227-10230
A joint approach combining free‐energy calculations and calcium‐imaging assays on the broadly tuned human 1G1 olfactory receptor is reported. The free energy of binding of ten odorants was computed by means of molecular‐dynamics simulations. This state function allows separating the experimentally determined eight agonists from the two non‐agonists. This study constitutes a proof‐of‐principle for the computational deorphanization of olfactory receptors. 相似文献
63.
Henry W. Orton Dr. Jan Stanek Dr. Tobias Schubeis Dylan Foucaudeau Claire Ollier Dr. Adrian W. Draney Dr. Tanguy Le Marchand Dr. Diane Cala-De Paepe Prof. Dr. Isabella C. Felli Prof. Dr. Roberta Pierattelli Prof. Dr. Sebastian Hiller Dr. Wolfgang Bermel Dr. Guido Pintacuda 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(6):2400-2405
64.
Angus Campbell Dr. Ian Mat Som Dr. Claire Wilson Prof. Dr. J. Stephen Clark 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1155-1160
Six members of the asbestinin family of marine diterpene natural products have been synthesized in an efficient and stereoselective manner from a single oxa-bridged intermediate. Five of these natural products have not been synthesized previously and the structures of four of them have been confirmed as those proposed originally or following revisions to the original structures. The fifth natural product—asbestinin-21—has been shown to be a diastereomer of the compound that had been proposed previously. 相似文献
65.
Jinny Claire Lee Hye Yun Kim Sejin Lee Jisu Shin Hyunjin Vincent Kim Kyeonghwan Kim Seungyeop Baek Donghee Lee Hanna Jeon DaWon Kim Seung‐Hoon Yang Gyoonhee Han Keunwan Park Jaeho Choi Jinwoo Park Jason A. Moss Kim D. Janda YoungSoo Kim 《Angewandte Chemie (International ed. in English)》2020,59(28):11491-11500
Amyloid‐β (Aβ) oligomers are implicated in Alzheimer disease (AD). However, their unstable nature and heterogeneous state disrupts elucidation of their explicit role in AD progression, impeding the development of tools targeting soluble Aβ oligomers. Herein parallel and anti‐parallel variants of Aβ(1–40) dimers were designed and synthesized, and their pathogenic properties in AD models characterized. Anti‐parallel dimers induced cognitive impairments with increased amyloidogenesis and cytotoxicity, and this dimer was then used in a screening platform. Through screening, two FDA‐approved drugs, Oxytetracycline and Sunitinib, were identified to dissociate Aβ oligomers and plaques to monomers in 5XFAD transgenic mice. In addition, fluorescent Astrophloxine was shown to detect aggregated Aβ in brain tissue and cerebrospinal fluid samples of AD mice. This screening platform provides a stable and homogeneous environment for observing Aβ interactions with dimer‐specific molecules. 相似文献
66.
Lorne Tallet Emilie Frisch Mgane Bornerie Claire Medemblik Benoît Frisch Philippe Lavalle Gilles Guichard Cline Douat Antoine Kichler 《Molecules (Basel, Switzerland)》2022,27(5)
There is an urgent need to develop new therapeutic strategies to fight the emergence of multidrug resistant bacteria. Many antimicrobial peptides (AMPs) have been identified and characterized, but clinical translation has been limited partly due to their structural instability and degradability in physiological environments. The use of unnatural backbones leading to foldamers can generate peptidomimetics with improved properties and conformational stability. We recently reported the successful design of urea-based eukaryotic cell-penetrating foldamers (CPFs). Since cell-penetrating peptides and AMPs generally share many common features, we prepared new sequences derived from CPFs by varying the distribution of histidine- and arginine-type residues at the surface of the oligourea helix, and evaluated their activity on both Gram-positive and Gram-negative bacteria as well as on fungi. In addition, we prepared and tested new amphiphilic block cofoldamers consisting of an oligourea and a peptide segment whereby polar and charged residues are located in the peptide segment and more hydrophobic residues in the oligourea segment. Several foldamer sequences were found to display potent antibacterial activities even in the presence of 50% serum. Importantly, we show that these urea-based foldamers also possess promising antifungal properties. 相似文献
67.
Marie‐Claire Giel Christopher J. Smedley Emily R. R. Mackie Taijie Guo Jiajia Dong Tatiana P. Soares da Costa John E. Moses 《Angewandte Chemie (International ed. in English)》2020,59(3):1181-1186
The boom in growth of 1,4‐disubstituted triazole products, in particular, since the early 2000’s, can be largely attributed to the birth of click chemistry and the discovery of the CuI‐catalyzed azide–alkyne cycloaddition (CuAAC). Yet the synthesis of relatively simple, albeit important, 1‐substituted‐1,2,3‐triazoles has been surprisingly more challenging. Reported here is a straightforward and scalable click‐inspired protocol for the synthesis of 1‐substituted‐1,2,3‐triazoles from organic azides and the bench stable acetylene surrogate ethenesulfonyl fluoride (ESF). The new transformation tolerates a wide selection of substrates and proceeds smoothly under metal‐free conditions to give the products in excellent yield. Under controlled acidic conditions, the 1‐substituted‐1,2,3‐triazole products undergo a Michael addition reaction with a second equivalent of ESF to give the unprecedented 1‐substituted triazolium sulfonyl fluoride salts. 相似文献
68.
Hossein Vahabi Laurent Ferry Claire Longuet Rodolphe Sonnier Claire Negrell-Guirao Ghislain David José-Marie Lopez-Cuesta 《European Polymer Journal》2012,48(3):604-612
The influence of phosphonated groups on thermal degradation and flammability has been investigated in the case of two chemically modified PMMA. Thermogravimetric analysis as well as pyrolysis combustion flow calorimetry have been used to define the efficiency of phosphorus in both condensed and vapor phases. A theoretical study was also performed to determine the contribution of phosphonated groups to the effective heat of combustion, residue content and heat release capacity. Empirical and theoretical approaches agreed to highlight that PMMA modified with monophosphonated comonomer is more efficient in both condensed and vapor phases in terms of flammability and char formation. These results were attributed to the ability of phosphonate groups to interact with ester groups and also to the weakness of the P–C–N bonds. Moreover, this study proposes a method for designing the chemical environment of phosphonate group in polymers to achieve better flame retardancy. 相似文献
69.
Fave C Hissler M Sénéchal K Ledoux I Zyss J Réau R 《Chemical communications (Cambridge, England)》2002,(16):1674-1675
In plane parallel arrangement and enhancement of NLO-activity are observed upon coordination of heteroditopic dipoles containing a phosphole ring on square-planar d8-palladium centre. 相似文献
70.
Double-quantum filtered MAS NMR spectra of an isolated homonuclear spin-1/2 pair are considered, at and away from rotational resonance conditions. The pulse sequence used is the solid-state NMR equivalent of double-quantum filtered COSY, known from solution-state NMR. The 119Sn spin pair in [(chex3Sn)2S] is characterized by a difference in isotropic chemical shielding smaller than the two chemical shielding anisotropies and by direct dipolar and isotropic J-coupling constants of similar magnitudes. At rotational resonance, one-dimensional double-quantum filtered 119Sn lineshapes yield the relative orientation of the two 119Sn chemical shielding tensors. Good double-quantum filtration efficiencies are found at and away from rotational resonance conditions, despite the presence of large chemical shielding anisotropies. Numerical simulations illustrate the interplay of the direct dipolar and J-coupling pathways and identify the latter as the main pathway even at rotational resonance conditions. 相似文献