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991.
Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2014,189(7-8):1102-1131
AbstractThis article describes the asymmetric synthesis of chiral organophosphorus compounds using methods of enantioselective hydride reduction and hydrogenation of corresponding unsaturated compounds. Many applications in stereoselective synthesis with reference to updated literature findings as well as the author's original research are discussed. The uses of chiral organophosphorus compounds in some asymmetric transformations leading to the formation of phosphorus analogues of important natural compounds were also presented. 相似文献
992.
Evgeny Galenin Vyacheslav Baumer Iaroslav Gerasymov Sergii Tkachenko Oleg Sidletskiy 《Crystal Research and Technology》2015,50(2):150-154
Bismuth germanate shaped crystals have been grown by the EFG (Stepanov) method. The correlation between growth rate, shape of crystals, their optical and scintillation parameters has been analysed. Optical and scintillation characteristics of the EFG crystals are similar to those obtained with Czochralski grown crystals, however, growth rate in EFG is by 2.5 times larger. Also we compare the photochromic effect under UV‐irradiation in EFG and Czochralski grown crystals. Material losses at fabrication of plates, pixels, and rods from EFG shaped plates may be reduced by ∼50% compared to large diameter boules. 相似文献
993.
Dr. Oleg V. Maltsev Dr. Naba K. Nath Prof. Dr. Panče Naumov Prof. Dr. Lukas Hintermann 《Angewandte Chemie (International ed. in English)》2014,53(3):847-850
The chemistry of firefly bioluminescence is important for numerous applications in biochemistry and analytical chemistry. The emitter of this bioluminescent system, firefly oxyluciferin, is difficult to handle. The cause of its lability was clarified while its synthesis was reinvestigated. A side product was identified and characterized by NMR spectroscopy and X‐ray crystallography. The reason for the lability of oxyluciferin is now ascribed to autodimerization of the coexisting enol and keto forms in a Mannich‐type reaction. 相似文献
994.
A Series of Potent CREBBP Bromodomain Ligands Reveals an Induced‐Fit Pocket Stabilized by a Cation–π Interaction 下载免费PDF全文
Timothy P. C. Rooney Dr. Panagis Filippakopoulos Dr. Oleg Fedorov Dr. Sarah Picaud Wilian A. Cortopassi Duncan A. Hay Dr. Sarah Martin Dr. Anthony Tumber Dr. Catherine M. Rogers Dr. Martin Philpott Dr. Minghua Wang Dr. Amber L. Thompson Dr. Tom D. Heightman Dr. David C. Pryde Dr. Andrew Cook Prof. Dr. Robert S. Paton Dr. Susanne Müller Prof. Dr. Stefan Knapp Dr. Paul E. Brennan Prof. Dr. Stuart J. Conway 《Angewandte Chemie (International ed. in English)》2014,53(24):6126-6130
The benzoxazinone and dihydroquinoxalinone fragments were employed as novel acetyl lysine mimics in the development of CREBBP bromodomain ligands. While the benzoxazinone series showed low affinity for the CREBBP bromodomain, expansion of the dihydroquinoxalinone series resulted in the first potent inhibitors of a bromodomain outside the BET family. Structural and computational studies reveal that an internal hydrogen bond stabilizes the protein‐bound conformation of the dihydroquinoxalinone series. The side chain of this series binds in an induced‐fit pocket forming a cation–π interaction with R1173 of CREBBP. The most potent compound inhibits binding of CREBBP to chromatin in U2OS cells. 相似文献
995.
Dr. Christofer Lendel Dr. Morten Bjerring Dr. Anatoly Dubnovitsky Robert T. Kelly Dr. Andrei Filippov Prof. Dr. Oleg N. Antzutkin Prof. Dr. Niels Chr. Nielsen Prof. Dr. Torleif Härd 《Angewandte Chemie (International ed. in English)》2014,53(47):12756-12760
Oligomeric and protofibrillar aggregates formed by the amyloid‐β peptide (Aβ) are believed to be involved in the pathology of Alzheimer’s disease. Central to Alzheimer pathology is also the fact that the longer Aβ42 peptide is more prone to aggregation than the more prevalent Aβ40. Detailed structural studies of Aβ oligomers and protofibrils have been impeded by aggregate heterogeneity and instability. We previously engineered a variant of Aβ that forms stable protofibrils and here we use solid‐state NMR spectroscopy and molecular modeling to derive a structural model of these. NMR data are consistent with packing of residues 16 to 42 of Aβ protomers into hexameric barrel‐like oligomers within the protofibril. The core of the oligomers consists of all residues of the central and C‐terminal hydrophobic regions of Aβ, and hairpin loops extend from the core. The model accounts for why Aβ42 forms oligomers and protofibrils more easily than Aβ40. 相似文献
996.
New Functional Cyclic Aminomethylphosphine Ligands for the Construction of Catalysts for Electrochemical Hydrogen Transformations 下载免费PDF全文
Dr. Elvira I. Musina Vera V. Khrizanforova Igor D. Strelnik Murad I. Valitov Yulia S. Spiridonova Dr. Dmitry B. Krivolapov Dr. Igor A. Litvinov Dr. Marsil K. Kadirov Dr. Peter Lönnecke Prof. Dr. Evamarie Hey‐Hawkins Prof. Dr. Yulia H. Budnikova Prof. Dr. Andrey A. Karasik Prof. Dr. Oleg G. Sinyashin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(11):3169-3182
Eight‐membered cyclic functional bisphosphines, namely 1,5‐di‐aryl‐3,7‐di(2‐pyridyl)‐1,5‐diaza‐3,7‐diphosphacyclooctanes (aryl=2‐pyridyl, m‐tolyl, p‐tolyl, diphenylmethyl, benzyl, (R)‐(+)‐(α‐methyl)benzyl), with 2‐pyridyl substituents on the phosphorus atoms have been synthesized by condensation of 2‐pyridylphosphine, formaldehyde, and the corresponding primary amine. The structures of some of these bisphosphines have been investigated by X‐ray crystallography. The bisphosphines readily form neutral P,P‐chelate complexes [(κ2‐P,P‐L)MCl2], cationic bis‐P,P‐chelate complexes [(κ2‐P,P‐L)2M]2+, or a five‐coordinate complex [(κ2‐P,P‐L)2NiBr]Br. The electrochemical behavior of two of the nickel complexes, and their catalytic activities in electrochemical hydrogen evolution and hydrogen oxidation, including the fuel‐cell test, have been studied. 相似文献
997.
Vakakis Alexander F. Gendelman Oleg V. Bergman Lawrence A. Mojahed Alireza Gzal Majdi 《Nonlinear dynamics》2022,108(2):711-741
Nonlinear Dynamics - Following a brief review of current progress in the field of nonlinear targeted energy transfer (TET), we discuss some general ideas and methods in this field and describe... 相似文献
998.
Ivan N. Bardasov Anastasiya U. Alekseeva Viktor A. Tafeenko Oleg V. Ershov 《合成通讯》2013,43(23):3343-3351
The one-pot reaction of aromatic aldehydes, malononitrile dimer, and triethylamine unexpectedly led to ammonium salts of not previously assumed 5,7-diamino-4-aryl-2-(dicyanomethyl)-1,4-dihydro-1,8-naphthyridine-3,6-dicarbonitriles, but the isomeric 5,7-diamino-4-aryl-2-(dicyanomethyl)-1,4-dihydro-1,6-naphthyridine-3,8-dicarbonitriles. Following neutralization and dehydrogenation led to the new, annulated with pyridine ring tricyanopyridines (TCPy). 相似文献
999.
Eugene S. Gladkov Sergey M. Desenko Irina S. Konovalova Ulrich Groth Oleg V. Shishkin Elena V. Vashchenko Valentin A. Chebanov 《Journal of heterocyclic chemistry》2013,50(Z1):E189-E192
Three‐component heterocyclization of 4‐amino‐5‐carboxamido‐1,2,3‐triazole, thiopyran‐3‐one‐1,1‐dioxide, and aromatic aldehydes under ultrasonic and microwave irradiation was studied. Regardless of the reaction parameters, 5,6,7,9‐tetrahydro‐4H‐thiopyrano[3,2‐d][1,2,3]triazolo[1,5‐a]pyrimidine‐8,8‐dioxides were isolated as sole reaction products whose structures were proven with help of NMR data and X‐ray analysis. 相似文献
1000.
Oleg V. Mikhailov Marina A. Kazymova Tatyana A. Shumilova Svetlana S. Solovieva 《Transition Metal Chemistry》2004,29(7):732-736
Novel complexing processes in the CuII-thiocarbohydrazide-diacetyl triple system proceeding to a copper(II)hexacyanoferrate gelatin-immobilized matrix system in contact with aqueous-alkaline (pH 12) solutions containing thiocarbohydrazide and diacetyl, have been studied. It has been shown that mild template synthesis of copper(II) coordination compounds with (N,S,N,S)- and (N,N,N,N)- tetradentate ligands - 4,5-dimethyl-2,3,6,7-tetraazaoctadien-3,5-dithiohydrazide-1,8 and 3,10-dithio--6,7,13,14-tetramethyl-1,2,4,5,8,9,11,12-octaazacyclotetradecatetraene-1,5,7,12 take place, respectively. At the same time, the complexing process in the system under examination, when it occurs in aqueous-ethanol solution between CuCl2 and the organic compounds indicated, leads to copper(II) coordination compounds with another (N,S,N,S)-tetradentate ligand - 3,9,10,16-tetramethyl-6,13--dimercapto-2,17-dioxo-4,5,7,8,11,12,14,15-tetraazaoctadecahexaene - 3,6,8,10,12,15. In both cases, thiocarbohydrazide and diacetyl are ligand synthons in these complexing processes. 相似文献