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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.
The photoreduction processes stimulated either the cw (power density 105–106 W/cm2) or pulsed (pulse energy 3–4 J, pulse duration 200 ns, effective laser spot diameter 1 mm) radiation of a CO2 laser on the surfaces of fused and crystalline quartz, as well as of natural silicates (nepheline KNa3[AlSiO4]4, rhodonite CaMn4[Si5O15], and zircon ZrSiO4), are studied. The X-ray emission analysis of irradiated surfaces showed that the laser irradiation of these materials leads
to the sublimation of silicon oxides and the enrichment of surfaces with constituent metal elements. Laser radiation also
stimulates the formation of silicon and metal nanoclusters on irradiated surfaces. The appearance of these nanoclusters is
confirmed by both photoluminescence and X-ray emission studies of irradiated surfaces. 相似文献