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981.
Karel Pomeisl Marcela Krečmerová Radek Pohl Robert Snoeck Graciela Andrei 《Tetrahedron》2019,75(39):130529
With respect to the strong antiviral activity of (S)-1-[3-hydroxy-2-(phosphonomethoxy)propyl]-5-azacytosine various types of its side chain fluorinated analogues were prepared. The title compound, (S)-1-[3-fluoro-2-(phosphonomethoxy)propyl]-5-azacytosine (FPMP-5-azaC) was synthesised by the condensation reaction of (S)-2-[(diisopropoxyphosphoryl)methoxy)-3-fluoropropyl p-toluenesulfonate with a sodium salt of 5-azacytosine followed by separation of appropriate N1 and O2 regioisomers and ester hydrolysis. Transformations of FPMP-5-azaC to its 5,6-dihydro-5-azacytosine counterpart, amino acid phosphoramidate prodrugs and systems with an annelated five-membered imidazole ring, i.e. imidazo [1,2-a][1,3,5]triazine derivatives were also carried out. 1-(2-Phosphonomethoxy-3,3,3-trifluoropropyl)-5-azacytosine was prepared from 5-azacytosine and trifluoromethyloxirane to form 1-(3,3,3-trifluoro-2-hydroxypropyl)-5-azacytosine which was treated with diisopropyl bromomethanephosphonate followed by deprotection of esters. Antiviral activity of all newly prepared compounds was studied. FPMP-5-azaC diisopropyl ester inhibited the replication of herpes viruses with EC50 values that were about three times higher than that of the reference anti-HCMV drug ganciclovir without displaying cytotoxicity. 相似文献
982.
Yabin Wen Ruth I. J. Amos Mohammad Talebi Roman Szucs John W. Dolan Christopher A. Pohl Paul R. Haddad 《Electrophoresis》2019,40(18-19):2415-2419
983.
Katrin Paschke Gunnar Blume Nils Werner André Müller Bernd Sumpf Johannes Pohl David Feise Peter Ressel Alexander Sahm Roland Bege Julian Hofmann Daniel Jedrzejczyk Günther Tränkle 《Optical Review》2018,25(1):149-159
Watt-class visible laser light with a high luminance can be created with high-power GaAs-based lasers either directly in the red spectral region or using single-pass second harmonic generation (SHG) for the colors in the blue–yellow spectral region. The concepts and results of red- and near infrared-emitting distributed Bragg reflector tapered lasers and master oscillator power amplifier systems as well as their application for SHG bench-top experiments and miniaturized modules are presented. Examples of these high-luminance light sources aiming at different applications such as flying spot display or holographic 3D cinema are discussed in more detail. The semiconductor material allows an easy adaptation of the wavelength allowing techniques such as six-primary color 3D projection or color space enhancement by adding a fourth yellow color. 相似文献
984.
An efficient cooling mechanism of magnetically trapped, highly excited antihydrogen (H) atoms is presented. This cooling, in addition to the expected evaporative cooling, results in trapping of a large number of H atoms in the ground state. It is found that the final fraction of trapped atoms is insensitive to the initial distribution of H magnetic quantum numbers. Expressions are derived for the cooling efficiency, demonstrating that magnetic quadrupole (cusp) traps provide stronger cooling than higher order magnetic multipoles. The final temperature of H confined in a cusp trap is shown to depend as approximately 2.2T(n0)n(0)(-2/3) on the initial Rydberg level n0 and temperature T(n0). 相似文献
985.
The emission of silver ions from the apex of an amorphous electrolyte tip has been investigated by field ion microscopy. The ion emission patterns show discrete nanometer-sized spots. We present evidence that they represent the termination of bulk ion conduction pathways at the solid-vacuum interface. The analysis of the signals from individual emission sites suggests the existence of a network of such pathways in the solid. Auto- and cross-correlation measurements of the currents from individual sites provide quantitative information on the microscopic dynamics of charge transport in solid electrolytes as well as on the lateral extent of the pathway network. 相似文献
986.
Ohne Zusammenfassung 相似文献
987.
H. Pohl 《Fresenius' Journal of Analytical Chemistry》1965,212(2):333-334
Ohne Zusammenfassung 相似文献
988.
K. Cruse H. Sperlich H. Freytag Martha Wildau Th. Breyhan und H. Pohl 《Fresenius' Journal of Analytical Chemistry》1955,146(1):52-59
Ohne Zusammenfassung 相似文献
989.
K. Brodersen G. Denk H. Specker H. Pohl F. Weigel A. Kurtenacker und H. Zellner 《Fresenius' Journal of Analytical Chemistry》1955,144(5):367-377
Ohne Zusammenfassung 相似文献
990.
K. Brodersen A. Kurtenacker H. Specker H. -F. Kurandt H. Pohl H. Schmidt und G. Denk 《Fresenius' Journal of Analytical Chemistry》1955,148(5):369-376
Ohne Zusammenfassung 相似文献