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1.
A series of 2-substituted benzimidazoles was synthesized. These products were consecutively converted into 5-nitro- and 5-amino-2-substituted benzimidazoles.Russian People's Friendship University, 117198 Moscow. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 493–500, April, 200.  相似文献   
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9-Methylnaphtho[2,1-b][1,6]naphthyrldine and 2,3-dimethyl-1-azaphenanthrene were obtained on a K-16 dehydrogenating catalyst from N-(1,2,5-trimethyl-4-piperidylidene)--naphthylamine, while N-cyclohexylidene--naphthylamine yielded N-phenyl--naphthylamine and benzo[a]carbazole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1400–1403, October, 1972.  相似文献   
4.
The dissociative ionization of 4-azafluorene and its methyl and phenyl derivatives was investigated. The relative intensity of the [M — CH3]+ ion peak depends on the position of the CH3 group in the 4-azafluorene ring. It was established that the loss of an RCN particle (R=H, CH3, and C6H5) for unsubstituted 4-azafluorene takes place from the M+ and [M — H]+ ion, exclusively from the [M — H]+ ion for the methyl-substituted compounds, and from the [M — H]+ and [H — 2H]+ fragments for the phenyl-substituted derivatives. Randomization of the deuterium ions in the 9,9-d2-4-azafluorene molecular ion was observed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–250, February, 1978.  相似文献   
5.
The Favorskii reaction with 1,2,5-trimethyl-4-piperidone and ethyl- and naphthylacetylenes gave the corresponding piperidols, the hydrogenation of which gave 1,2,5-trimethyl-4-nbutyl(or 2-naphthylethyl)-4-piperidols. 4-Phenyl- and 4-butyl-2,5-dimethylpyridine were condensed with formaldehyde, and some of the transformations of the resulting-hydroxyethyl derivatives were studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 349–352, March, 1973.  相似文献   
6.
The synthesis of noncondensed dipiperidylbenzene and tripiperidyl systems has been effected. Some derivatives of compounds of this series have been obtained.  相似文献   
7.
It is established that the surface of a monochromator for a point X-ray source in diffractometers is the surface of revolution of a circle arc around the straight line connecting the X-ray source and detector. It is shown that scattering occurs at the points of intersection of the monochromator surface with the set of ellipsoids of revolution, in whose focuses the X-ray source and detector are located. A formula is obtained for calculating the misorientation angle of mosaic blocks. The limits of variation in the angle for Fe \(K_{\alpha _1 } \), Cu \(K_{\alpha _1 } \), and Mo \(K_{\alpha _1 } \) radiations are determined. It is shown that there is no unified continuous reflecting monochromator surface, and the true reflecting surface is fractal.  相似文献   
8.
Derivatives of 1-hydroxy-2,5-dimethylpiperid-4-one substituted at the hydroxy and the carbonyl groups have now been prepared and the IR spectra of some of them have been studied. 1-Nitroso-2,5-dimethylpiperid-4-one has been prepared from 2,5-dimethylpiperid-4-one and subjected to various reactions at the nitroso- and the carbonyl groups. The IR spectra of the N-nitroso-compounds prepared are discussed.  相似文献   
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We consider a 2-periodic function f continuous on and changing its sign at 2s points y i [–, ). For this function, we prove the existence of a trigonometric polynomial T n of degree n that changes its sign at the same points y i and is such that the deviation |f(x) – T n(x)| satisfies the second Jackson inequality.  相似文献   
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