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排序方式: 共有955条查询结果,搜索用时 15 毫秒
771.
Henry W. Orton Jan Stanek Tobias Schubeis Dylan Foucaudeau Claire Ollier Adrian W. Draney Tanguy Le Marchand Diane Cala‐De Paepe Isabella C. Felli Roberta Pierattelli Sebastian Hiller Wolfgang Bermel Guido Pintacuda 《Angewandte Chemie (International ed. in English)》2020,59(6):2380-2384
Narrow proton signals, high sensitivity, and efficient coherence transfers provided by fast magic‐angle spinning at high magnetic fields make automated projection spectroscopy feasible for the solid‐state NMR analysis of proteins. We present the first ultrahigh dimensional implementation of this approach, where 5D peak lists are reconstructed from a number of 2D projections for protein samples of different molecular sizes and aggregation states, which show limited dispersion of chemical shifts or inhomogeneous broadenings. The resulting datasets are particularly suitable to automated analysis and yield rapid and unbiased assignments of backbone resonances. 相似文献
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Fei Lu Julia Rodriguez-Garcia Isabella Van Damme Nicholas J. Westwood Liz Shaw James S. Robinson Geoff Warren Afroditi Chatzifragkou Simon McQueen Mason Leonardo Gomez Laura Faas Kelvin Balcombe Chittur Srinivasan Fiorella Picchioni Paul Hadley Dimitris Charalampopoulos 《Current Opinion in Green and Sustainable Chemistry》2018
774.
Isabella G. Alonso Lais T. Yamane Verônica S. de Freitas-Blanco Luiz F.T. Novaes Michelle Franz-Montan Eneida de Paula Marili V.N. Rodrigues Rodney A.F. Rodrigues Julio C. Pastre 《Tetrahedron》2018,74(38):5192-5199
A 5-step synthesis of spilanthol (affinin) is reported, where the route features complete control of alkene geometry during the assembling of the double bonds, with the use of a Sonogashira cross-coupling reaction, a Z-selective alkyne semi-reduction and a HWE olefination reaction as the key steps. A simplified analogue was also prepared in 4 steps. Both compounds were found to permeate dermatomed pig ear skin through an in vitro Franz-type diffusion cell. The simplified analogue presented a superior anesthetic effect in vivo, using the tail flick model, when compared to spilanthol and to the commercial standard EMLA®. These results suggest that both spilanthol and its analogue could be useful as a topical anesthetic in clinical practice. 相似文献
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Anna Pavlova Diane L. Lynch Isabella Daidone Laura Zanetti-Polzi Micholas Dean Smith Chris Chipot Daniel W. Kneller Andrey Kovalevsky Leighton Coates Andrei A. Golosov Callum J. Dickson Camilo Velez-Vega Jos S. Duca Josh V. Vermaas Yui Tik Pang Atanu Acharya Jerry M. Parks Jeremy C. Smith James C. Gumbart 《Chemical science》2021,12(4):1513
The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an attractive target for antiviral therapeutics. Recently, many high-resolution apo and inhibitor-bound structures of Mpro, a cysteine protease, have been determined, facilitating structure-based drug design. Mpro plays a central role in the viral life cycle by catalyzing the cleavage of SARS-CoV-2 polyproteins. In addition to the catalytic dyad His41–Cys145, Mpro contains multiple histidines including His163, His164, and His172. The protonation states of these histidines and the catalytic nucleophile Cys145 have been debated in previous studies of SARS-CoV Mpro, but have yet to be investigated for SARS-CoV-2. In this work we have used molecular dynamics simulations to determine the structural stability of SARS-CoV-2 Mpro as a function of the protonation assignments for these residues. We simulated both the apo and inhibitor-bound enzyme and found that the conformational stability of the binding site, bound inhibitors, and the hydrogen bond networks of Mpro are highly sensitive to these assignments. Additionally, the two inhibitors studied, the peptidomimetic N3 and an α-ketoamide, display distinct His41/His164 protonation-state-dependent stabilities. While the apo and the N3-bound systems favored Nδ (HD) and Nϵ (HE) protonation of His41 and His164, respectively, the α-ketoamide was not stably bound in this state. Our results illustrate the importance of using appropriate histidine protonation states to accurately model the structure and dynamics of SARS-CoV-2 Mpro in both the apo and inhibitor-bound states, a necessary prerequisite for drug-design efforts.The main protease (Mpro) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an attractive target for antiviral therapeutics. 相似文献
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Isabella M. Burtscher Edvin Johansson Stig Holts Freddy Sthlberg 《Magnetic resonance imaging》1999,17(10):351-1519
A new phantom and evaluation method for experimental evaluation of 1H-magnetic resonance spectroscopy single volume localization techniques regarding signal contamination (C), defined as the part of the signal originating outside the volume of interest, is presented. The quality assessment method is based on a spherical phantom with an oil/water interface in order to reduce susceptibility effects, and applied for stimulated-echo acquisition method (STEAM) and spin-echo (SE) sequences, echo times of 270, 135, and 10 ms, and cubic volumes of interest (VOI) of 13, 1.53, 23, 2.53, and 33 cm3. To be able to mimic measurements of the contamination in three dimensions the physical gradients representing the three orthogonal directions for slice selection were shifted in the pulse sequences. Contamination values in one dimension differed between 6.5% and 8.4% in SE sequences, and between 0.7% and 13.8% in STEAM sequences. In STEAM sequences a decrease of C with increasing VOI size was observed while SE sequences showed comparable C values for the different VOI sizes tested. The total contamination in three dimensions were 19% and 18% in SE and STEAM sequences with a TE of 270 ms, and 7% in a STEAM sequence with a TE of 10 ms, respectively. The presented evaluation method is easily applied to the new phantom and showed high reproducibility. 相似文献