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91.
Matienko Ludmila Zhigacheva Irina Mil Elena Albantova Anastasia Goloshchapov Alexander 《Molecules (Basel, Switzerland)》2022,27(11)
The role of ligands in the regulation of the catalytic activity of Ni-complexes (Ni(acac)2) in green process-selective ethylbenzene oxidation with O2 into α-phenyl ethyl hydroperoxide is considered in this article. The dual function of phenol (PhOH) included in the coordination sphere of the nickel complex as an antioxidant or catalyst depends on the ligand environment of the metal. The role of intermolecular H-bonds and supramolecular structures (AFM method) in the mechanisms of selective catalysis by nickel complexes in chemical and biological oxidation reactions is analyzed. 相似文献
92.
Vasily A. Kezin Elena S. Matyugina Mikhail S. Novikov Alexander O. Chizhov Robert Snoeck Graciela Andrei Sergei N. Kochetkov Anastasia L. Khandazhinskaya 《Molecules (Basel, Switzerland)》2022,27(9)
Pyrimidine nucleoside analogues are widely used to treat infections caused by the human immunodeficiency virus (HIV) and DNA viruses from the herpes family. It has been shown that 5-substituted uracil derivatives can inhibit HIV-1, herpes family viruses, mycobacteria and other pathogens through various mechanisms. Among the 5-substituted pyrimidine nucleosides, there are not only the classical nucleoside inhibitors of the herpes family viruses, 2′-deoxy-5-iodocytidine and 5-bromovinyl-2′-deoxyuridine, but also derivatives of 1-(benzyl)-5-(phenylamino)uracil, which proved to be non-nucleoside inhibitors of HIV-1 and EBV. It made this modification of nucleoside analogues very promising in connection with the emergence of new viruses and the crisis of drug resistance when the task of creating effective antiviral agents of new types that act on other targets or exhibit activity by other mechanisms is very urgent. In this paper, we present the design, synthesis and primary screening of the biological activity of new nucleoside analogues, namely, 5′-norcarbocyclic derivatives of substituted 5-arylamino- and 5-aryloxyuracils, against RNA viruses. 相似文献
93.
Maria E. Nikolaeva Andrey V. Nechaev Elena V. Shmendel Roman A. Akasov Mikhail A. Maslov Andrey F. Mironov 《Molecules (Basel, Switzerland)》2022,27(9)
Upconverting nanoparticles have unique spectral and photophysical properties that make them suitable for development of theranostics for imaging and treating large and deep-seated tumors. Nanoparticles based on NaYF4 crystals doped with lanthanides Yb3+ and Er3+ were obtained by the high-temperature decomposition of trifluoroacetates in oleic acid and 1-octadecene. Such particles have pronounced hydrophobic properties. Therefore, to obtain stable dispersions in aqueous media for the study of their properties in vivo and in vitro, the polyethylene glycol (PEG)-glycerolipids of various structures were obtained. To increase the circulation time of PEG-lipid coated nanoparticles in the bloodstream, long-chain substituents are needed to be attached to the glycerol backbone using ether bonds. To prevent nanoparticle aggregation, an L-cysteine-derived negatively charged carboxy group should be included in the lipid molecule. 相似文献
94.
Polymer-dispersed liquid crystal (PDLC) systems based on polysulfone as carrying matrix and 4-cyano-4?-pentylbiphenyl (5CB) liquid crystal (LC) were obtained as thin transparent films. The PDLC films were prepared by solvent- and thermally induced phase separation methods, with various compositions in the two components. Information on the phase separation was obtained by polarised light optical microscopy, differential scanning calorimetry and scanning electron microscopy. The PDLC composites show well-defined droplets of submicrometric size, around 650 nm for a medium content of LC and around 250 nm for a low one. The droplets show a radial configuration and a homeotropic alignment of the LC molecules within. By contact angle measurement and surface free energy calculations, it was established that self-assembling of aliphatic units of the two composite components, at droplet interface, is the driving force of the homeotropic alignment. Moreover, these data indicated the potential biocompatibility of the studied composites. The photophysical behaviour shows a better light emission of the PDLCs containing bigger droplets. 相似文献
95.
Novel semiflexible polyazomethines containing chromophoric units into azomethine mesogenic core have been synthesised by condensation of a flexible dialdehyde with mesogenic diamines containing fluorene, antraquinone, pyrimidine, azobenzene and benzophenone. The thermotropic behaviour of the resulting polyazomethines was assessed by differential scanning calorimetry, polarised light microscopy and investigations of the miscibility relations. While the pure polyazomethines showed a birefringent viscous texture difficult to be ascribed, by mixing with a liquid crystal dimer, clear Schlieren or marbled textures were observed, indicating a nematic mesophase. The polymers exhibited violet, blue or yellow light emission. 相似文献
96.
Roberta Cavalli Emilio Marengo Otto Caputo Elena Ugazio Maria Rosa Gasco 《Journal of Dispersion Science and Technology》2013,34(7):717-734
The influence of twenty five different alcohols on the formation of warm oil-in-water (O/W) microemulsions was investigated. Selected concentrations of each alcohol were added to fixed amounts of stearic acid, Tween 20 and water at 65 ° C. Fifteen alcohols formed microemulsions, at least at one of the concentrations. A pattern recognition study was performed to elucidate the activities of the alcohols by Principal Component Analysis (PCA). Linear Discriminant Analysis (LDA) was used to classify them. Two classification functions, obtained for alcohols forming / not forming microemulsions, suggest that the formation of warm O/W microemulsion is linked to the nature and the dimension/lipophilicity of the alcohol. 相似文献
97.
Irina L. Odinets Oleg I. Artyushin Elena V. Sharova Ekaterina V. Matveeva Alexandr N. Turanov Vasilii K. Karandashev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):146-149
Abstract The extraction properties of a series of carbamoylmethylphosphine oxides and β-aminophosphine oxides with lanthanide metal ions is presented. Tris[bis(2-diphenyl- phosphorylethyl)-aminoethyl]amine is shown to be highly effective for extraction of Re(VII). 相似文献
98.
Viviana De Luca Paolo Digiamberardino Giovanna Di Pasquale Salvatore Graziani Antonino Pollicino Elena Umana Maria Gabriella Xibilia 《Journal of Polymer Science.Polymer Physics》2013,51(9):699-734
Smart systems adapt to the surrounding environments in a number of ways. They are capable to scavenge energy from available sources, sense and elaborate external stimuli and adequately react. Electro Active Polymers are playing a main role in the realization of smart systems for applications if fields such as bio inspired and autonomous robotics, medicine, and aerospace. This paper focus on the possibility to use Ionic Polymer Metal Composites as a class of materials relevant to the realization of post silicon smart systems. The three main aspects of this new technology, i.e., fabrication methods, modeling, and applications are described with emphasis to most recent results. Attention is given to main challenges and shortcomings to be solved for technology, modelling, and control of IPMC based devices that need to be solved before this new technology can be fully exploited in real world applications. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013 相似文献
99.
Elena B. Averina Yuri V. Samoilichenko Yulia A. Volkova Yuri K. Grishin Victor B. Rybakov Andrei G. Kutateladze Mikhail E. Elyashberg Tamara S. Kuznetsova Nikolai S. Zefirov 《Tetrahedron letters》2012,53(12):1472-1475
Revised regiochemistry for the heterocyclization of electrophilic alkenes with tetranitromethane (TNM) in the presence of triethylamine, providing rapid access to nitroisoxazoles, is reported. The formation of 5-nitroisoxazoles previously incorrectly assigned as 3-nitro regioisomers, has now been established unambiguously by X-ray crystallography. Empirical computations with ACD/CNMR Predictor, based both on hierarchical ordering of spherical environments (HOSE) and an algorithm of artificial neural networks (ANN), and also Density Functional Theory computations of the 13C NMR chemical shifts for the 3- versus 5-nitroisoxazoles are shown to consistently match the spectra of the experimentally observed 5-regioisomers. 相似文献
100.
Jessica Cid Dr. Jorge J. Carbó Dr. Elena Fernández 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(40):12794-12802
Most trivalent boron reagents are electrophiles owing to the vacancy for two electrons to fill the outer orbital of boron; however, interestingly, trivalent boron compounds can change their electrophilic character to a nucleophilic character by only changing the nature of the substituents on the boron atoms. With the help of computational tools, we have analyzed the structural‐ and electronic properties of boryl fragments that were either bonded to main‐group metals or coordinated to transition‐metals/rare‐earth‐metals and we have designed a map that might help to identify certain trends. This trend map will be useful for selecting an appropriate trivalent boron compound, depending on the sought reactivity. 相似文献