On neutron surface waves

It is shown that neutron surface waves do not exist. The difference between the neutron wave mechanics and the wave physics of electromagnetic and acoustic processes, which allows the existence of surface waves, is analyzed.     

Comparative study of the biological activity of organosilicon and organogermanium compounds

The literature data and the results of our own investigations on the comparative study of the biological activity of isostructural organogermanium and organosilicon compounds have been summarized. It has been shown that the series of organogermanium and organosilicon compounds is more active than the carbon analogues, the majority of organogermanium compounds are less toxic than the sila analogues, the biological activity of the compounds under study appears to be similar but can dramatically differ in the degree of activity, and, moreover, in some particular cases sila and germa analogues exhibit the opposite biological effects.     

Synthesis and Stereoisomerization of 2-(1-Alkoxyimino-2,2,2-trifluoroethyl)-5-trimethylsilylfurans

2-(1-Alkoxyimino-2,2,2-trifluoroethyl)-5-trimethylsilylfurans were synthesized by the condensation of 2-(trifluoroacetyl)-5-trimethylsilylfuran with alkoxyamines. According to ¹H and ¹⁹F NMR spectroscopic data, the alkoxyimino group in the E-isomers descreens the H-3 and H-4 protons of the furan ring more strongly than in the Z-isomers, shifting their signals downfield. The fluorine atoms of the α-trifluoromethyl group in the Z-isomer are characterized by a downfield shift in relation to the E-isomer. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 834–838, June, 2005.     

Heteroorganic furan derivatives. 61. Trimethyl(5-methyl-2-furyl)silane and trimethyl(5-methyl-2-furyl)germane

The transformations of trimethyl(5-methyl-2-furyl)silane and trimethyl(5-methyl-2-furyl)germane were studied upon vapor-phase oxidation by atmospheric oxygen on a V-Mo-Ag-O catalyst. Under these conditions, trimethyl(5-formyl-2-furyl)-silane and trimethyl(5-formyl-2-furyl)germane are formed albeit in only 5–7% yield. This low yield is a consequence of the thermal instability of the starting compounds and the aldehydes formed. The oxidation of 2-methyl-5-tert-butylfuran was studied under comparable conditions. The corresponding aldehyde was obtained in 30% yield. A scheme was proposed for the catalytic oxidation of 5-substituted 2-methylfurans.For Communication 60, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 22–24, January, 1987.     

Tetranuclear Heterometallic {Zn2Eu2} Complexes With 1‐Naphthoate Anions: Synthesis,Structure and Photoluminescence Properties

A series of new tetranuclear heterometallic Zn^II‐Eu^III complexes have been synthesized, that is, (bpy)₂Zn₂Eu₂(naph)₁₀ ( 1 ), (bpy)₂Zn₂Eu₂(naph)₈(NO₃)₂ ( 2 ), and (phen)₂Zn₂Eu₂(naph)₈(NO₃)₂ ( 3 ), and other ones, where naph^? is the 1‐naphthoate anion, bpy=2,2′‐bipyridyl, and phen=1,10‐phenanthroline. The solid‐phase complexes consist of large supramolecular ensembles due to stacking interactions between the aromatic ligands. Photoluminescence (PL) measurements were carried out to study PL spectra, lifetimes and quantum yields (QY) of the synthesized complexes at different temperatures. The external QY for the solid phases of complexes under UV excitation was found to exceed 20 %. It has been shown that partial replacement of naphthoate ligands in the coordination environment of Eu³⁺ by NO₃^? anions influences the PL properties. To investigate the behavior of these complexes in solvent, we dissolved complex 3 in MeCN, put it on a transparent glass as a substrate, and studied the PL properties at room temperature.     

Synthesis,structure and biological activity of new 6,6‐dimethyl‐2‐oxo‐4‐{2‐[5‐organylsilyl(germyl)]furan(thiophen)‐2‐yl}vinyl‐5,6‐dihydro‐2H‐pyran‐3‐carbonitriles

New 6,6‐dimethyl‐2‐oxo‐4‐{2‐[5‐alkylsilyl(germyl)]furan(thiophen)‐2‐yl}vinyl‐5,6‐dihydro‐2H‐pyran‐3‐carbonitriles (IC₅₀: 1–6 µg ml^?1) have been prepared by the condensation of corresponding silicon‐ and germanium‐containing furyl(thienyl)‐2‐carbaldehydes with 3‐cyano‐4,6,6‐trimethyl‐5,6‐dihydropyran‐2‐one using piperidine acetate as a catalyst. The obtained carbonitriles were identified using NMR (¹H, ¹³C and ²⁹Si) spectroscopy and GC‐MS. The structure of 6,6‐dimethyl‐2‐oxo‐4‐[2‐(5‐trimethylsilyl)thiophen‐2‐yl]‐5,6‐dihydro‐2H‐pyran‐3‐carbonitrile was studied using X‐ray diffractometry. The influences of the heterocycle and the structure of the organoelement substituent on cytotoxicity and on matrix metalloproteinase inhibition have been studied. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis,structure and cytotoxicity of new 2‐[(3‐aminopropyl)dimethylsilyl]‐5‐furfural diethylacetals and 2‐[(3‐aminopropyl)dimethylsilyl]‐5‐phenylfurans

Novel 2‐[(3‐aminopropyl)dimethylsilyl]‐5‐furfural diethylacetals and 2‐[(3‐aminopropyl)di‐methylsilyl]‐5‐phenylfurans have been synthesized by a hydrosilylation reaction of aliphatic and heterocyclic N‐allylamines in the presence of the Speier's catalyst. The effects of the structure of the amine and nature of organic substituent at the furan ring on the cytotoxicity of the new compounds have been studied. Copyright © 2013 John Wiley & Sons, Ltd.     

Analytical calculation of the neutron spectrum for direct measurement of <Emphasis Type="Italic">NN</Emphasis> scattering at pulsed reactor Yaguar

Analytical calculation of a single-neutron-detector counts per YAGUAR reactor pulse is presented and comparison with coincidence scheme is given. The text was submitted by the authors in English.     

Synthesis and crystal structure of 5-tert-butyldimethylsilyl-2-(2,2,2-trifluoro-hydroxyiminoethyl)furan

The oximation of 5-tert-butylmethylsilyl-2-(trifluoroacetyl)furan with hydroxylamine leads to the exclusive formation of the E-isomer of 5-tert-butyldimethylsilyl-2-(2,2,2-trifluorohydroxyiminoethyl)- furan.     

Reductive transformations of Schiff bases in the synthesis of functionally substituted heteroaromatic amines

Schiff bases synthesized by condensation of 5- and 6-aminoquinolines, 5-amino-2-methylquinoline, nitroanilines, and pyrimidinylaminoanilines with substituted benzaldehydes and pyridinecarbaldehydes were reduced with sodium tetrahydridoborate in acetic acid to obtain the corresponding N-aryl(hetaryl)benzylamines, N-(pyridylmethyl)anilines, and N-(1,2,3,4-tetrahydroquinolyl)benzylamine derivatives. The reduction of arylhetarylimines with hydrazine hydrate in the presence of Raney nickel involved only the azomethine C=N bond, while the nitrogen-containing heteroaromatic ring remained intact. Under analogous conditions, nitrosubstituted Schiff bases and benzyl- and pyridylmethylamines were converted into previously unknown N-(aminobenzyl)quinolinamines and aryl(pyridyl)methyl-substituted phenylenediamines.