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991.
Polyfluorinated diarylacetonitriles were obtained by the reaction of polyfluoroaromatic compounds with acetonitrile in the presence of Me3SnN(SiMe3)2 and CsF. 相似文献
992.
Dr. Dmitry S. Perekalin Dr. Valentin V. Novikov Alexander A. Pavlov Igor A. Ivanov Dr. Natalia Yu. Anisimova Alexey N. Kopylov Dr. Dmitry S. Volkov Dr. Irina F. Seregina Prof. Dr. Michail A. Bolshov Prof. Dr. Alexander R. Kudinov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):4923-4925
Melittin is a membrane‐active peptide from bee venom with promising antimicrobial and anticancer activity. Herein we report on a simple and selective method for labeling of the tryptophan residue in melittin by the organometallic fragment [(C5H5)Ru]+ in aqueous solution and in air. Ruthenium coordination does not disturb the secondary structure of the peptide (as verified by 2D NMR spectroscopy), but changes the pattern of its intermolecular interactions resulting in an 11‐fold decrease of hemolytic activity. The high stability of the organometallic conjugate allowed the establishment of the biodistribution of the labeled melittin in mice by inductively coupled plasma MS analysis of ruthenium. 相似文献
993.
994.
Mol’kova E. A. Shchegravina E. S. Otvagin V. F. Kuzmina N. S. Malysheva Yu. B. Svirshchevskaya E. V. Zaburdaeva E. A. Fedorov A. Yu. 《Russian Chemical Bulletin》2022,71(3):564-571
Russian Chemical Bulletin - A series of colchicine and thiocolchicine derivatives bearing a Michael acceptor moiety in ring A were synthesized. Some of these compounds exhibit cytotoxic activity in... 相似文献
995.
Serkov S. A. Sigai N. V. Kostikova N. N. Fedorov A. E. Gazieva G. A. 《Russian Chemical Bulletin》2022,71(8):1801-1805
Russian Chemical Bulletin - A general and efficient method for the synthesis of S-substituted 5-sulfanylmethyl(ethyl)-1,3,4-thiadiazol-2-amines via cyclocondensation of aryl(benzyl)sulfanylacetic... 相似文献
996.
Debopreeti Mukherjee Pablo Trigo-Mouriño Yuan Jiang Timothy Nowak Vladimir Shchurik Donovon A. Adpressa Michael T. Louie Shane R. Reynolds Michael J. Hohn Mohammad Ahmed Al-Sayah Gregory F. Pirrone Alexey A. Makarov 《Journal of separation science》2022,45(12):2055-2063
Recent advances in the field of cancer biology have accelerated the discovery and development of novel biopharmaceuticals. At the forefront of these drug development efforts are high-throughput screening, compressed timelines, and limited sample quantities, all characteristic of the discovery space. To meet program targets, large numbers of protein variants must be produced, screened, and characterized, presenting a daunting analytical challenge. Additionally, the higher-order structure is paramount for protein function and must be monitored as a critical quality attribute. Matrix-assisted laser desorption/ionization mass spectrometry has been utilized as an ultra-fast, automatable, sample-sparing analytical tool for biomolecules. Our group has published applications integrating hydrogen-deuterium exchange mass spectrometry with matrix-assisted laser desorption/ionization mass spectrometry for the rapid conformational characterization of small proteins, the current work expands this application to monoclonal and bi-specific antibodies. This study demonstrates the ability of the methodology, matrix-assisted laser desorption/ionization hydrogen-deuterium exchange mass spectrometry, to detect conformational differences between bi-specific antibodies from different expression hosts. These conformational differences were validated by orthogonal techniques including circular dichroism, nuclear magnetic resonance, and size-exclusion chromatography hydrogen-deuterium exchange mass spectrometry. This work demonstrates the utility of applying the developed methodology as a rapid conformational screening tool to triage samples for further analytical characterization. 相似文献
997.
Zhirayr Avetisyan Alexey Karapetyants 《Mathematical Methods in the Applied Sciences》2023,46(1):811-829
We introduce and study in a general setting the concept of homogeneity of an operator and, in particular, the notion of homogeneity of an integral operator. In the latter case, homogeneous kernels of such operators are also studied. The concept of homogeneity is associated with transformations of a measure—measure dilations, which are most natural in the context of our general research scheme. For the study of integral operators, the notions of weak and strong homogeneity of the kernel are introduced. The weak case is proved to generate a homogeneous operator in the sense of our definition, while the stronger condition corresponds to the most relevant specific examples—classes of homogeneous integral operators on various metric spaces—and allows us to obtain an explicit general form for the kernels of such operators. The examples given in the article—various specific cases—illustrate general statements and results given in the paper and at the same time are of interest in their own way. 相似文献
998.
999.
1000.
D. Yu. Usachov A. V. Fedorov O. Yu. Vilkov A. V. Erofeevskaya A. S. Vopilov V. K. Adamchuk D. V. Vyalikh 《Physics of the Solid State》2015,57(5):1040-1047
The intercalation of silicon under graphene on the Co(0001) surface, which is accompanied by the formation of a silicon solid solution in cobalt and by the formation of a surface crystalline Co2Si phase, has been investigated using photoelectron spectroscopy. It has been shown that the formation of cobalt silicide leads to a substantial weakening of the hybridization of electronic states of graphene and cobalt and to the recovery of the Dirac spectrum of electronic states of graphene near the Fermi level. This has made it possible to investigate the electron doping of graphene on the cobalt silicide substrate upon deposition of lithium on its surface. It has been found that doping with lithium leads to a significant charge transfer onto graphene, and the electron concentration reaches 3.1 × 1014 cm?2. Moreover, the specific form of the Fermi surface creates favorable conditions for the enhancement of the electron-phonon coupling. As a result, the formed system can be considered as a candidate for the creation of superconductivity in single-layer graphene. 相似文献