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Mathematical Notes - 相似文献
3.
V. I. Shvedov I. A. Kharizomenova A. N. Grinev 《Chemistry of Heterocyclic Compounds》1975,11(6):664-665
2,3-Polymethylene-4-oxo-3,4-dihydrothieno[2,3-d]pyrimidine derivatives were obtained by reaction of esters of α-aminothiophene-β-carboxylic acids with lactame or α-aminothiophene-Β-carboxylic acids with lactims. Desulfuration of the thienopyrimidines obtained in this manner is a convenient method for the synthesis of pyrrolo-, pyrido-, and azepino[1,2-a]pyrimidine derivatives. 相似文献
4.
V. I. Shvedov V. K. Vasil'eva I. A. Kharizomenova A. N. Grinev 《Chemistry of Heterocyclic Compounds》1975,11(6):666-668
A method is proposed for the synthesis of isatin analogs — 4,5-dioxothieno[2,3-b] pyrroles and 5,6-dioxothieno[3,2-b]pyrroles — by reaction of oxalyl chloride with amino-substituted α-amino- and Β-aminothiophene. The thiosemicarbazones of 4-ary1-5,6-dioxothieno[3,2-b]pyrroles were synthesized. n]mis|See [1] for communication X. 相似文献
5.
The corresponding 6- and 3-formyl derivatives were obtained by formylation of 2-methyl-3-carbethoxy-5-methoxy- and 2-methyl-5-methoxyindole derivatives.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–341, March, 1971. 相似文献
6.
L. M. Alekseeva G. G. Dvoryantseva I. V. Persianova Yu. N. Sheinker M. V. Mezentseva V. I. Shvedov A. N. Grinev 《Chemistry of Heterocyclic Compounds》1976,12(5):576-582
The protonation of pyrrolo [1,2-] pyrimidine and 6, 7, 8, 9-tetrahydropyrimido [1, 2-] indole derivatives in CF3COOH (at –15 to +25° C) and in CF3COOH/H2SO4 (at 25°) was studied by PMR spectroscopy. The investigated compounds form monocations, the structure of which corresponds to the addition of a proton to the carbon atom of th pyrrole fragment in the position to the bridge nitrogen atom.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 686–692, May, 1976. 相似文献
7.
V. I. Shvedov V. K. Vasil'eva A. N. Grinev N. P. Kostyuchenko 《Chemistry of Heterocyclic Compounds》1971,7(6):707-709
2-Methyl-3-ethoxycarbonyl-4-(N,N-dimethylhydrazino)thiophene (II) and 2-methyl-3-ethoxy-carbonyl-4-(N-phenylhydrazino)thiophene (III) are formed by the action of substituted hydrazines — N,N-dimethylhydrazine and phenylhydrazine — on 2-methyl-3-ethoxycarbonyl-4-hydroxythiophene (I). At the same time, the thiophene ring of hydroxythiophene I undergoes hydrazinolysis under the influence of hydrazine hydrate to form 3-mercaptomethyl-4-ethoxycarbonyl-5-methylpyrazole (IV). Structure IV was proved by IR, UV, and PMR spectroscopy and by hydrogenolysis of IV to the known 3,5-dimethyl-4-ethoxycarbonylpyrazole (V).Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 759–761, June, 1971. 相似文献
8.
V. I. Shvedov I. A. Kharizomenova L. B. Altukhova A. N. Grinvev 《Chemistry of Heterocyclic Compounds》1970,6(3):400
Continuing investigations in the field of the synthesis of condensed heterocyclic systems containing pyrrole and indole fragments ¦1–3¦, we have condensed of 2-aminopyrrole derivatives with various 1, 3-dicarbonyl compounds. The reaction took place at the boil in solutions in pyridine or acetic acid, and also without a solvent at 150–160° C, forming in a single stage derivatives of pyrrolo[1, 2-a]pyrimidine (I–III) and pyrrolo[2, 1-b]-tetrahydroquinazoline (IV–VI). The condensation of 2-aminopyrrole with acetoacetic and substituted acetoacetic esters led to 4-oxo derivatives of pyrrolo[1, 2-]pyrimidine (VII and VIII). 相似文献
9.
V. I. Shvedov G. N. Kurilo A. A. Cherkasova A. N. Grinev 《Chemistry of Heterocyclic Compounds》1973,9(8):965-967
The cyclization of the di(phenylhydrazone) of methyl -phenyl-,-dioxobutyrate with hydrazines has given phenylhydrazones of methyl indol-2-ylglyoxylates, which have been reduced to methyl -aminoindol-2-ylacetates. Some reactions of these compounds have been studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1040–1042, August, 1973. 相似文献
10.
V.?V.?Shpe?zman N.?N.?Peschanskaya P.?N.?Yakushev A.?S.?Smolyanski? A.?S.?Shvedov V.?G.?Cheremisov 《Physics of the Solid State》2010,52(2):265-270
Development of deformation jumps in the creep of poly(methyl methacrylate) (PMMA) has been studied. The structural levels
of deformation have been determined from the creep rate oscillation periods (deformation jumps) measured by the interferometric
method. Special attention is given to a new method of data processing, which enables one to reveal previously undetectable
nanoscale deformation jumps. By the example of PMMA specimens preliminarily exposed to γ radiation with doses D=55–330 kGy and unexposed specimens, the presence of nanoscale deformation jumps with the values dependent on the dose D and time of creep has been shown. The obtained results confirm the existence of 10–20-nm domains in amorphous polymers and
make it possible to study the multilevel organization of the deformation process, starting from the nanoscale. 相似文献