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11.
Indoles and pyrrole were subjected to hetarylation with imidazole and benzimidazole in the presence of aliphatic, aromatic, and heteroaromatic carboxylic acid chlorides. The resulting N,N-diacylimidazolinyl- and N,N-diacylbenzimidazolinylindoles were converted to 2-(3-indolyl)-1,3-diacylimidazolium and N,N-diacylbenzimidazolium salts by the action of trityl perchlorate.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 238–247, February, 1977.  相似文献   
12.
1.  It has been determined experimentally that for a given level of power input, the limiting surface area Smax achieved in size-reduction increases, and the rate constant for the size-reduction of metal halide crystals decreases with increasing bond energy of the crystal lattice in the order KCl < nacl="">< naf="">< lif.="">
2.  A parameter is proposed for describing the size-reduction of metal halides both in the step in which destruction is overcome, and in the process in which dynamic equilibrium is established between the processes of particle dispersion and aggregation.
3.  Relationships have been obtained that make it possible to calculate precisely Smax for any metal halide with the NaCl structure by using the Smax value of any other metal halide regardless of its defect structure.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 7, pp. 1466–1470, July, 1989.  相似文献   
13.
The reaction of 4-(3-indolyl)pyrimidine methiodide with alkali gives a stable anhydro base, which reacts under mild conditions with methyl iodide to give 1-methyl-4-(1-methyl-3-indolyl)pyrimidinium iodide. On the basis of the calculated molecular diagrams of both compounds it was concluded that they have high reactivities. The reaction of the anhydro base with an aqueous methanol solution of KOH, concentrated NH4OH, hydrazine hydrate, and a mixture of malonic acid dinitrile with triethylamine leads to 3-acetylindole, 4-(3-indolyl)pyrimidine, 3(5)-(3-indolyl)pyrazole, and 2-amino-3-cyano-6-(3-indolyl)pyridine, respectively. 1-Methyl-4-(1-methyl-3-indolyl)pyrimidinium iodide under the same conditions gives similar compounds that contain a methyl group attached to the indole nitrogen atom. The structures of the synthesized compounds were confirmed by their IR, UV, PMR, and mass spectra.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 212–218, February, 1982.  相似文献   
14.
The synthesis of 6-oxodibenzo[a,g]quinolizinium perchlorate — an analog of the alkaloid berberine — and a number of its derivatives, including mesoionic compounds, was accomplished on the basis of a 1-unsubstituted 3-(2-methylenecarboxyaryl)-2-benzopyrylium salt. The interconversions of the compounds obtained in this research were studied.See [1] for communication 26.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1381–1387, October, 1982.  相似文献   
15.
Oxazolo[3,2-f]xanthines were synthesized by the reaction of 7-acylalkyl-8-bromo-3-methyl- and -1,3-dimethylxanthines with sodium benzoate in dimethylformamide. Their alkylation with methyl iodine was studied. The reaction of oxazolo[3,2-f]xanthines with primary amines leads to the previously described imidazo[1,2-f]xanthines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 534–537, April, 1988.  相似文献   
16.
1-Amino-2-R-benzimidazoles are oxidized by lead tetraacetate to give, depending on the substituent in the 2-position, either to 1,1-azobenzimidazoles (R=H, CH3, C6H5, Cl, N(CH3)2) or 3-R-benzo-1,2,4-triazines (R=NH2, NHCH3, NHC6H5, OH). The factors affecting the course of the reaction are discussed. The physicochemical properties of the 1,1-azobenzimidiazoles obtained have been examined.For preliminary communication, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1486–1499, November, 1989.  相似文献   
17.
Previously undescribed pyrimidine betaines with cycloammonium and triphenylphosphonium cations were obtained. A study of the UV, IR, PMR, and mass spectra made it possible to draw a conclusion regarding the noncyclic structure of betaines stabilized by an intramolecular donor-acceptor interaction of the charge-transfer complex (CTC) type.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1687–1690, December, 1978.  相似文献   
18.
sym-Triazolo[3,4-b][1,2,4,5]tetraazepines were obtained by condensation of 4-amino-3-hydrazino-1,2,4-triazoline-5-thione with -dicarbonyl compounds, and 1-[4-amino-1,2,4-triazol-3-yl]-3,5-dialkylpyrazoles were obtained by condensation of the same thione with -dicarbonyl compounds.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 555–559, April, 1978.  相似文献   
19.
The lipid composition of the free fatty acids of the seed oil ofMalva sylvestris from the Ukrainian flora has been studied by chromato-mass spectrometry. The fatty acid composition was represented by 20 compounds, among which malvic and sterculic acids were detected. The presence of terpineols and retinol has been shown.Zaporozh'e Medical Institute. Translated from Khimiya Prirodnykh Soedenii, No. 3, pp. 322–325, May–June, 1994.  相似文献   
20.
The mass spectra of dimethylbenzyl- and dimethyldibenzylpyridines at different ionizing electron energies were investigated. The anomalously low intensities of the molecular ion peaks of 3,4-dibenzylpyridines, as compared with the 2,5-isomers, and the greater probability of the formation of primary (M-2)+ ions in the mass spectra are explained by the synchronous loss of a neutral H2 particle and the formation of cyclic fragment ions from the weakly excited molecular ions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 70–73, January, 1973.  相似文献   
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