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61.
正Phosphorus-containing organic compounds are important feedstock for the synthesis of value-added bioactive molecules. Therefore, the development of highly efficient synthetic methods for the construction of phosphorus-element bonds has drawn huge attention in the past decades [1].Particularly, the formation of P–C bonds from phosphoruscentered radicals has been demonstrated to be one of the most efficient and convenient strategies, which has been widely applied for the synthesis of organic phosphorus compounds in recent years. 相似文献
62.
Lasse Jrgensen Cehofski Anders Kruse Alexander Nrgaard Alsing Benn Falch Sejergaard Jonas Ellegaard Nielsen Anders Schlosser Grith Lykke Sorensen Jakob Grauslund Bent Honor Henrik Vorum 《Molecules (Basel, Switzerland)》2022,27(11)
Aflibercept is a frequently used inhibitor of vascular endothelial growth factor (VEGF) in the treatment of macular edema following central retinal vein occlusion (CRVO). Retinal proteome changes following aflibercept intervention in CRVO remain largely unstudied. Studying proteomic changes of aflibercept intervention may generate a better understanding of mechanisms of action and uncover aspects related to the safety profile. In 10 Danish Landrace pigs, CRVO was induced in both eyes with an argon laser. Right eyes were treated with intravitreal aflibercept while left control eyes received isotonic saline water. Retinal samples were collected 15 days after induced CRVO. Proteomic analysis by tandem mass tag-based mass spectrometry identified a total of 21 proteins that were changed in content following aflibercept intervention. In retinas treated with aflibercept, high levels of aflibercept components were reached, including the VEGF receptor-1 and VEGF receptor-2 domains. Fold changes in the additional proteins ranged between 0.70 and 1.19. Aflibercept intervention resulted in a downregulation of pigment epithelium-derived factor (PEDF) (fold change = 0.84) and endoplasmin (fold change = 0.91). The changes were slight and could thereby not be confirmed with less precise immunohistochemistry and Western blotting. Our data suggest that aflibercept had a narrow mechanism of action in the CRVO model. This may be an important observation in cases when macular edema secondary to CRVO is resistant to aflibercept intervention. 相似文献
63.
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
64.
Lei Ji Stefan Riese Alexander Schmiedel Marco Holzapfel Maximillian Fest Jrn Nitsch Basile F. E. Curchod Alexandra Friedrich Lin Wu Hamad H. Al Mamari Sebastian Hammer Jens Pflaum Mark A. Fox David J. Tozer Maik Finze Christoph Lambert Todd B. Marder 《Chemical science》2022,13(18):5205
Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2′-yl)-o-carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive ‘mixed’ state of 1-(pyren-2′-yl)-o-carborane are very small, and all three excited states are accessible at room temperature. The internal-conversion and reverse internal-conversion between LE and CT states are significantly faster than the radiative decay, and the two states have the same lifetimes and are in thermodynamic equilibrium.Reversible conversion between excited-states is key to many photophysical phenomena. We studied the equilibrium between LE and CT states by time-resolved and temperature-dependent fluorescence, fs- and ns-transient absorption, and LR-TDDFT calculations. 相似文献
65.
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
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