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21.
22.
E. A. Burakova I. V. Saranina N. V. Tikunova V. N. Sil´nikov 《Russian Chemical Bulletin》2015,64(6):1400-1405
Antibacterial activity of tetracationic compounds based on 1,4-diazabicyclo[2.2.2]octane (DABCO) bis-quaternary salts with dodecyl substituents bound by linker groups containing four carbon atoms was studied. All the compounds exhibited activity against the test-strains under study. The gram-positive culture S. aureus was found to be the most sensitive to the influence of compounds in question. The highest activity against S. aureus was exhibited by the compounds containing a but-2-yne or a butane linker; their efficiency exceeded that of the reference compound, antibiotic Ciprofloxacin. For the gram-negative culture P. aeruginosa, the highest activity was exhibited by the compound containing a but-2-yne linker. The compounds with a but-2-yne or a butane linker are stable in the presence of nitrogen-containing nucleophiles, which makes them promising for further studies. 相似文献
23.
L. I. Belen´kii M. Kh. Mamarakhmonov A. N. Subbotin N. D. Chuvylkin 《Russian Chemical Bulletin》2015,64(5):1032-1038
Density functional theory quantum chemical calculations of thermodynamic stabilities in the gas phase and in water were carried out for 1,3,4-oxadiazole and 1,3,4-thiadiazole, 1,2,4-1H-triazole and 1,2,4-4H-triazole, 1,2,3,4-1H-tetrazole and 1,2,3,4-2H-tetrazole molecules, and for cationic and bipolar (carbenoid) intermediates formed by these molecules in electrophilic substitution reactions (with proton as model electrophile) and the results obtained are compared. Differences in the chemical behavior of pairs of isomeric 1H- and 4H-1,2,4-triazoles and 1H- and 2H-tetrazoles are analyzed. 相似文献
24.
O. A. Luk´yanov G. V. Pokhvisneva T. V. Ternikova G. A. Smirnov 《Russian Chemical Bulletin》2015,64(5):1062-1064
Chlorides and anhydrides of carboxylic (including dicarboxylic) acids react with salts of 1-methoxy-3-methyl-1-triazene 2-oxides to give the corresponding 3-acyl-1-methoxy-3-methyl-1-triazene 2-oxides. 相似文献
25.
Rozhkov A. V. Basova G. V. Korshunov A. O. Bochkarev L. N. Glukhova T. A. Il´ichev V. A. 《Russian Chemical Bulletin》2015,64(8):1949-1954
Russian Chemical Bulletin - New norbornene monomer, viz., 5-[(bicyclo[2.2.1]hept-5-en-2-ylmethoxy)methyl]-8-[(dimesitylboryl)oxy]quinoline (1), was synthesized. The copolymers based on monomer 1... 相似文献
26.
Khisamutdinov G. Kh. Karpychev Yu. V. Zhbanova Yu. S. Kondyukov I. Z. Kashaev V. A. Il´in V. P. 《Russian Chemical Bulletin》2015,64(8):1967-1970
Known methods for the synthesis of 2,3-bis(nitroxymethyl)-2,3-dinitrobutane-1,4-diol dinitrate and its intermediates were investigated. New procedures were developed for the preparation of these compounds. 2,3-Bis(nitroxymethyl)-2,3-dinitrobutane-1,4-diol dinitrate was studied by X-ray diffraction.
相似文献27.
S. A. Nalet´ko M. G. Pervova M. I. Kodess M. S. Toporova T. I. Gorbunova A. Ya. Zapevalov V. I. Saloutin 《Russian Chemical Bulletin》2017,66(6):1011-1017
The CoCl2-catalyzed reactions of fluorinated 1,2-oxi- and thiiranes with acyl chlorides were studied. It was found that a regioselective heterocycle opening reaction resulted in two isomers having normal and abnormal structure in a ratio predetermined by the substituents in both the starting heterocycles and acyl chlorides. 相似文献
28.
O. V. Pokidova N. S. Emel´yanova N. I. Shkondina A. I. Kotel´nikov L. A. Syrtsova N. A. Sanina S. M. Aldoshin 《Russian Chemical Bulletin》2017,66(5):821-827
The decomposition of two neutral binuclear nitrosyl iron complexes (NICs) of the µ-S structural type and general composition [Fe2(SR)2(NO)4]0 was studied in comparison. The exchange reaction of the thiophenol or 2-aminothiophenol thiolate ligand by glutathione (GSH) in neutral NICs was studied. The reaction system was analyzed by spectrophotometry to prove the presence of a new NICs with the GS– ligand in it. It was found that, unlike the earlier studied binuclear cationic NICs of the µ-S type and general composition [Fe2(µ-SR)2(NO)4]2+SO4?nH2O with cysteamine and penicillamine ligands in which both thiolate ligands exchange by GS–, in these neutral complexes both thiolate ligands are de-tached by only one GSH ligand is attached. A water molecule is inserted into the second free site. It is assumed that the antitumor activity of the neutral NICs can be determined not only by their NO-donor activity but also by their ability to exchange the thiolate ligand by GS–, i.e., "to remove" GSH from the medium as in the case of cationic NICs. The discovered reaction can prevent, most likely, the S-glutathionylation of important metabolites in the presence of GSH and is very significant for metabolism of NICs. 相似文献
29.
Neshev N. I. Sokolova E. M. Kozub G. I. Kondrat´eva T. A. Sanina N. A. 《Russian Chemical Bulletin》2017,66(8):1510-1514
Russian Chemical Bulletin - The NO-donating and hemolytic activity of the binuclear tetranitrosyl iron complexes (TNIC) with thiolate ligands of the composition [Fe2(SR)2(NO)4], where R is... 相似文献
30.
Wijnands F. Pendry J. B. Garcia-Vidal F. J. Bell P. M. Roberts P. J. Moreno L. Marti´n 《Optical and Quantum Electronics》1997,29(2):199-216
We present a new formalism for calculating the Green's function for Maxwell's equations. As our aim is to apply our formalism
to light scattering at surfaces of arbitrary materials, we derive the Green's function in a surface representation. The only
requirement on the material is that it should have periodicity parallel to the surface. We calculate this Green's function
for light of a specific frequency and a specific incident direction and distance with respect to the surface. The material
properties entering the Green's function are the reflection coefficients for plane waves at the surface. Using the close relationship
between the Green's function and the density of states (DOS), we apply our method to calculate the spontaneous emission rate
as a function of the distance to a material surface. The spontaneous emission rate can be calculated using Fermi's Golden
Rule, which can be expressed in terms of the DOS of the optical modes available to the emitted photon. We present calculations
for a finite slab of cylindrical rods, embedded in air on a square lattice. It is shown that the enhancement or suppression
of spontaneous emission strongly depends on the frequency of the light.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献