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排序方式: 共有531条查询结果,搜索用时 203 毫秒
21.
Emilie Boulard Vivien Zibulski Luisa Oertel Dr. Philip Lienau Dr. Martina Schäfer Dr. Ursula Ganzer Dr. Ulrich Lücking 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(19):4378-4388
A short synthetic approach with broad scope to access five- to seven-membered cyclic sulfoximines in only two to three steps from readily available thiophenols is reported. Thus, simple building blocks were converted to complex molecular structures by a sequence of S-alkylation and one-pot sulfoximine formation, followed by intramolecular cyclization. Seventeen structurally diverse cyclic sulfoximines were prepared in high overall yields. In vitro evaluation of these underrepresented, three-dimensional, cyclic sulfoximines with respect to properties relevant to medicinal chemistry did not reveal any intrinsic flaw for application in drug discovery. 相似文献
22.
Quemet Alexandre Buravand Emilie Peres Jean-Gabriel Dalier Vincent Bejaoui Syriac 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):1051-1061
Journal of Radioanalytical and Nuclear Chemistry - This paper details the different steps for the isotopic determination of UAmO2 discs from analytical irradiation. MARIOS and DIAMINO irradiations... 相似文献
23.
24.
Thomas Michel Emilie Destandau Laëtitia Fougère Claire Elfakir 《Analytical and bioanalytical chemistry》2013,405(4):1431-1431
25.
Dr. Stuart Bogatko Dr. Emilie Cauët Dr. Eric Bylaska Dr. Gregory Schenter Dr. John Fulton Prof. John Weare 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3047-3060
Herein, we report on the structure and dynamics of the aqueous Ca2+ system studied by using ab initio molecular dynamics (AIMD) simulations. Our detailed study revealed the formation of well‐formed hydration shells with characteristics that were significantly different to those of bulk water. To facilitate a robust comparison with state‐of‐the‐art X‐ray absorption fine structure (XAFS) data, we employ a 1st principles MD‐XAFS procedure and directly compare simulated and experimental XAFS spectra. A comparison of the data for the aqueous Ca2+ system with those of the recently reported Zn2+, Fe3+, and Al3+ species showed that many of their structural characteristics correlated well with charge density on the cation. Some very important exceptions were found, which indicated a strong sensitivity of the solvent structure towards the cation′s valence electronic structure. Average dipole moments for the 2nd shell of all cations were suppressed relative to bulk water. 相似文献
26.
Kurt F. Hoffmann Dr. Anja Wiesner Dr. Simon Steinhauer Prof. Dr. Sebastian Riedel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(57):e202201958
Preparation and characterization of the dimeric Lewis superacid [Al(OTeF5)3]2 and various solvent adducts is presented. The latter range from thermally stable adducts to highly reactive, weakly bound species. DFT calculations on the ligand affinity of these Lewis acids were performed in order to rank their remaining Lewis acidity. An experimental proof of the Lewis acidity is provided by the reaction of solvent-adducts of Al(OTeF5)3 with [PPh4][SbF6] and OPEt3, respectively. Furthermore, their reactivity towards chloride and pentafluoroorthotellurate salts as well as (CH3)3SiCl and (CH3)3SiF is shown. This includes the formation of the dianion [Al(OTeF5)5]2−. 相似文献
27.
Thomas Wiesner Dr. Zhu Wu Dr. Jie Han Prof. Dr. Lei Ji Dr. Alexandra Friedrich Dr. Ivo Krummenacher Michael Moos Prof. Dr. Christoph Lambert Prof. Dr. Holger Braunschweig Benjamin Rudin Dr. Hilmar Reiss Olena Tverskoy Dr. Frank Rominger Prof. Dr. Andreas Dreuw Prof. Dr. Todd B. Marder Dr. Jan Freudenberg Prof. Dr. Uwe H. F. Bunz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202201919
Tetraiodotetraazapentacene I4TAP , the last missing derivative in the series of halogenated silylated tetraazapentacenes, was synthesized via condensation chemistry from a TIPS-ethynylated diaminobenzothiadiazol in three steps. Single and double reduction furnished its air-stable monoanion and relatively air-stable dianion, both of which were characterized by crystallography. All three species are structurally and spectroscopically compared to non-halogenated TAP and Br4TAP . I4TAP is an n-channel material in thin-film transistors with average electron mobilities exceeding 1 cm2 (Vs)−1. 相似文献
28.
Rebecca Wiesner Christin Scheller Finja Krebs Hermann Wätzig Imke Oltmann-Norden 《Electrophoresis》2021,42(3):206-218
The development of capillary electrophoresis, especially CE-SDS devices, has led CE-SDS to become an established tool in a wide range of applications in the analysis of biopharmaceuticals and is increasingly replacing its method of origin, SDS-PAGE. The goal of this study was to evaluate the comparability of molecular weight (MW) determination especially by CE-SDS and SDS-PAGE. For ensuring comparability, model proteins that have little or no posttranslational modifications and an IgG antibody were used. Only a minor influence of sample preparation conditions, including sample buffer, temperature conditions, and different reducing agents on the MW determination were found. In contrast, the selection of the MW marker plays a decisive role in determining the accurate apparent MW of a protein. When using different MW markers, the deviation in MW determination can exceed 10%. Interestingly, CE-SDS and 10% SDS-PAGE hardly differ in their trueness of MW determination. The trueness in relation to the reference MW for each protein was calculated. Although the trueness values for the model proteins considered range between 1.00 and 1.11 using CE-SDS, they range between 0.93 and 1.03 on SDS-PAGE, depending on the experimental conditions chosen. 相似文献
29.
Baudat Emilie Gautier Céline Fichet Pascal Destrel Eric Colin Christèle Giuliani Margaux Lambrot Gabriel 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):637-650
Journal of Radioanalytical and Nuclear Chemistry - 90Sr radiochemical method using nitric acid for Sr and Ca separation was optimized using design of experiments methodology. Nitric acid... 相似文献
30.
Zihui Li Hiroaki Sai Kwan Wee Tan Tobias N. Hoheisel Sol M. Gruner Ulrich Wiesner 《Journal of Sol-Gel Science and Technology》2014,70(2):286-291
A novel strategy for fabrication of ordered ceramic–metal nanocomposites was demonstrated by multifunctional block copolymer/metal nanoparticle self-assembly. Hybrid organic–inorganic block copolymer poly(3-methacryloxypropyl-T8-heptaisobutyl-polyhedral oligomeric silsesquioxane-block-N,N-dimethylaminoethyl methacrylate) was synthesized and used as a bi-functional structure directing agent for ligand-stabilized platinum nanoparticles to form ordered organic–inorganic nanocomposites with dense loading of inorganic species in both microphase separated domains. Subsequently, thin films of the hybrid material were converted to ordered silica (ceramic)–platinum (metal) nanocomposites via UV-assisted ozonolysis. This is the first time ordered ceramic–metal nanocomposites were achieved through a bottom-up approach, opening up opportunities for the design and synthesis of a broad range of ordered inorganic–inorganic nanocomposites. 相似文献