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排序方式: 共有443条查询结果,搜索用时 15 毫秒
1.
Practical synthesis of 1,3-diaryl-substituted 3-isothiocyanatopropan-1-ones based on the reaction of chalcones with thiocyanic acid generated in situ by treatment of thiocyanate ammonium with dilute sulfuric acid has been developed. 相似文献
2.
Babushkina Anastasia A. Mikhaylov Vladimir N. Novikov Alexander S. Sorokoumov Viktor N. Gureev Maxim A. Kryukova Mariya A. Shpakov Alexander O. Balova Irina A. 《Chemistry of Heterocyclic Compounds》2022,58(8-9):432-437
Chemistry of Heterocyclic Compounds - The Richter cyclization was used for the synthesis of 6-halo-3-(hydroxymethyl)cinnolin-4(1H)-ones. X-ray analysis revealed that these compounds exist as dimers... 相似文献
3.
Anastasia O. Kolesnikova Dmitry A. Kornilov Aidar T. Gubaidullin Vladimir D. Kiselev 《国际化学动力学杂志》2020,52(5):301-309
The kinetic parameters and enthalpies of the Diels–Alder reactions between cyclopentadiene and 2,3-dicyano-1,4-benzoquinone leading to the formation of two different monoadducts and bisadduct were determined. The stability of adducts is compared. Monoadduct appears to be thermodynamically more stable than the bisadduct. Comparison with the other Diels–Alder reactions studied previously allows us to conclude that the heat effects upon formation of the considered Diels–Alder adducts are the lowest in comparison with all the studied dienophiles. 相似文献
4.
Johannes Bitzer Steffen Otterbach Kavipriya Thangavel Anastasia Kultaeva Prof. Dr. Rochus Schmid Prof. Dr. Andreas Pöppl Prof. Dr. Wolfgang Kleist 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(25):5667-5675
Metal–organic frameworks containing multiple metals distributed over crystallographically equivalent framework positions (mixed-metal MOFs) represent an interesting class of materials, since the close vicinity of isolated metal centers often gives rise to synergistic effects. However, appropriate characterization techniques for detailed investigations of these mixed-metal metal–organic framework materials, particularly addressing the distribution of metals within the lattice, are rarely available. The synthesis of mixed-metal FeCuBTC materials in direct syntheses proved to be difficult and only a thorough characterization using various techniques, like powder X-ray diffraction, X-ray absorption spectroscopy and electron paramagnetic resonance spectroscopy, unambiguously evidenced the formation of a mixed-metal FeCuBTC material with HKUST-1 structure, which contained bimetallic Fe−Cu paddlewheels as well as monometallic Cu−Cu and Fe−Fe units under optimized synthesis conditions. The in-depth characterization showed that other synthetic procedures led to impurities, which contained the majority of the applied iron and were impossible or difficult to identify using solely standard characterization techniques. Therefore, this study shows the necessity to characterize mixed-metal MOFs extensively to unambiguously prove the incorporation of both metals at the desired positions. The controlled positioning of metal centers in mixed-metal metal–organic framework materials and the thorough characterization thereof is particularly important to derive structure–property or structure–activity correlations. 相似文献
5.
6.
Denis Kudryavtsev Anastasia Isaeva Daria Barkova Ekaterina Spirova Renata Mukhutdinova Igor Kasheverov Victor Tsetlin 《Molecules (Basel, Switzerland)》2021,26(5)
Slow-channel congenital myasthenic syndromes (SCCMSs) are rare genetic diseases caused by mutations in muscle nicotinic acetylcholine receptor (nAChR) subunits. Most of the known SCCMS-associated mutations localize at the transmembrane region near the ion pore. Only two SCCMS point mutations are at the extracellular domains near the acetylcholine binding site, α1(G153S) being one of them. In this work, a combination of molecular dynamics, targeted mutagenesis, fluorescent Ca2+ imaging and patch-clamp electrophysiology has been applied to G153S mutant muscle nAChR to investigate the role of hydrogen bonds formed by Ser 153 with C-loop residues near the acetylcholine-binding site. Introduction of L199T mutation to the C-loop in the vicinity of Ser 153 changed hydrogen bonds distribution, decreased acetylcholine potency (EC50 2607 vs. 146 nM) of the double mutant and decay kinetics of acetylcholine-evoked cytoplasmic Ca2+ rise (τ 14.2 ± 0.3 vs. 34.0 ± 0.4 s). These results shed light on molecular mechanisms of nAChR activation-desensitization and on the involvement of such mechanisms in channelopathy genesis. 相似文献
7.
Dr. Mojtaba Alidoost Anna Mangini Dr. Fabrizio Caldera Dr. Anastasia Anceschi Dr. Julia Amici Dr. Daniele Versaci Dr. Lucia Fagiolari Prof. Francesco Trotta Prof. Carlotta Francia Prof. Federico Bella Prof. Silvia Bodoardo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(6):e202104201
Manufactured globally on industrial scale, cyclodextrins (CD) are cyclic oligosaccharides produced by enzymatic conversion of starch. Their typical structure of truncated cone can host a wide variety of guest molecules to create inclusion complexes; indeed, we daily use CD as unseen components of food, cosmetics, textiles and pharmaceutical excipients. The synthesis of active material composites from CD resources can enable or enlarge the effective utilization of these products in the battery industry with some economical as well as environmental benefits. New and simple strategies are here presented for the synthesis of nanostructured silicon and sulfur composite materials with carbonized hyper cross-linked CD (nanosponges) that show satisfactory performance as high-capacity electrodes. For the sulfur cathode, the mesoporous carbon host limits polysulfide dissolution and shuttle effects and guarantees stable cycling performance. The embedding of silicon nanoparticles into the carbonized nanosponge allows to achieve high capacity and excellent cycling performance. Moreover, due to the high surface area of the silicon composite, the characteristics at the electrode/electrolyte interface dominate the overall electrochemical reversibility, opening a detailed analysis on the behavior of the material in different electrolytes. We show that the use of commercial LP30 electrolyte causes a larger capacity fade, and this is associated with different solid electrolyte interface layer formation and it is also demonstrated that fluoroethylene carbonate addition can significantly increase the capacity retention and the overall performance of our nanostructured Si/C composite in both ether-based and LP30 electrolytes. As a result, an integration of the Si/C and S/C composites is proposed to achieve a complete lithiated Si−S cell. 相似文献
8.
Ilya Kolesnikov Daria Mamonova Dmitrii Pankin Gulia Bikbaeva Anastasia Khokhlova Anna Pilip Anastasia Egorova Vladislav Zigel Alina Manshina 《Photochemistry and photobiology》2023,99(3):929-935
Modern progress in photopharmocology calls for new generation of compounds joining bioactivity, photoswitchable properties and high selectivity of response to light wavelength. Introduced here, phosphonate–fullerene hybrids are the first representatives of such compounds. Phosphonate–fullerene hybrids were synthesized on a base of fullerene C60 and organophosphates with the function of photoswitchable cholinesterase activity—phosphorylated thiazolotriazole and aminomalonate compounds and studied with FTIR, UV–VIS spectroscopy and IPC-micro neurotoxin amperometric analysis. As a result of spectroscopic and bioactivity characterization, it was not only demonstrated butyrylcholinesterase (BuChE) inhibition increase in phosphonate–fullerene hybrids compared with pure phosphonates but also pronounced response of inhibition degree to laser irradiation of hybrids. It was found opposite behavior of hybrids as a result of laser irradiation—BuChE inhibition drop-off for thiazolotriazole–fullerene and pronounced growth for aminomalonate–fullerene. The other remarkable peculiarity of presented phosphonate–fullerene hybrids is high selectivity of inhibition change degree to laser wavelength (266 or 325 nm). 相似文献
9.
Synthesis and Biological Evaluation of Several Dephosphonated Analogues of CMP‐Neu5Ac as Inhibitors of GM3‐Synthase 下载免费PDF全文
Dr. Paola Rota Dr. Federica Cirillo Dr. Marco Piccoli Dr. Antonio Gregorio Prof. Guido Tettamanti Prof. Pietro Allevi Prof. Luigi Anastasia 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14614-14629
Previous studies demonstrated that reducing the GM3 content in myoblasts increased the cell resistance to hypoxic stress, suggesting that a pharmacological inhibition of the GM3 synthesis could be instrumental for the development of new treatments for ischemic diseases. Herein, the synthesis of several dephosphonated CMP‐Neu5Ac congeners and their anti ‐ GM3‐synthase activity is reported. Biological activity testes revealed that some inhibitors almost completely blocked the GM3‐synthase activity in vitro and reduced the GM3 content in living embryonic kidney 293A cells, eventually activating the epidermal growth factor receptor (EGFR) signaling cascade. 相似文献
10.