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S. V. Shorshnev S. E. Esipov N. I. Yakushkina N. A. Kluyev V. G. Zhil'nikov A. I. Chernyshev 《Chemistry of Heterocyclic Compounds》1987,23(9):1002-1009
The conversion of pyrimido[5,4-e]-1,2,4-triazinediones to imidazo[4,5-e]-1,2,4-triazinones is a multistage process including the hydrolysis of the C(5)-N(6) amide bond, the closure of the ureido group to the imidazolidinone ring, decarboxylation, acid oxidation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1252–1259, September, 1987. 相似文献
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S. V. Shorshnev S. E. Esipov A. I. Chernyshev A. F. Pozharskii V. V. Kuz'menko A. V. Gulevskaya 《Chemistry of Heterocyclic Compounds》1990,26(2):191-200
It was shown that pyrimido[4,5-e]-1,2,4-triazine-6,8-diones enter the reversed azadiene synthesis reaction with ketones and vinyl ethyl ether in the presence of diethylamine or boron trifluoride etherate, and also with enamines. As a result of the reaction, pyrido[2,3-d]pyrimidine-2,4-diones are formed in good yield. Pyrimido[5,4-e]-1,2,4-triazine-5,7-diones do not undergo such reactions with acetone. The reasons for the unique behavior of the isomeric pyrimidotriazinediones in the reaction with acetone are discussed.For a preliminary communication, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 224–233, February, 1990. 相似文献
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Sh. A. Samsoniya M. V. Trapaidze S. V. Dolidze N. A. ésakiya L. N. Kurkovskaya N. N. Suvorov 《Chemistry of Heterocyclic Compounds》1988,24(9):992-999
Electrophilic-substitution reactions for 3H,8H-indolo[4,5-e]- and -[5,4-e]indole were studied. Mono- and disubstituted compounds were isolated as a result of formylation and acetylation, whereas only monosubstitution products were isolated in the case if diazo coupling. It is shown that in the dimethylaminomethylation of 3H,8H-indolo[4,5-e]indole steric factors hinder the formation of a disubstituted compound, while the formation of \-substitution products is hindered in the case of diazo coupling of 3H,8H-indolo[4,5-e]- and-[5,4-e]indole.See [1] for Communication 24.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1205–1212, September, 1988. 相似文献
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Dmitry B. Vinogradov Alexei N. Izmest'ev Angelina N. Kravchenko Natalya G. Kolotyrkina Galina A. Gazieva 《Journal of heterocyclic chemistry》2024,61(1):137-145
A method for the regioselective synthesis of imidazo[4,5-e][1,3]thiazino[2,3-c][1,2,4]triazine derivatives has been developed by the reaction of imidazotriazinethiones with ethyl phenylpropiolate upon treatment with potassium carbonate or sodium methoxide in methanol. The synthesis was accomplished by Michael-type addition of the imidazotriazinethiones to the triple bond of ethyl phenylpropiolate followed by subsequent intramolecular cyclization. 相似文献
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Samsoniya Sh. A. Trapaidze M. V. Dolidze S. V. Ésakiya N. A. Suvorov N. N. Kolesnikov A. M. Mikhailenko F. A. 《Chemistry of Heterocyclic Compounds》1984,20(3):283-288
New heterocyclic systems, viz., 3H,8H-indolo[4,5-e]indole and 3H,8H-indolo-[5,4-e]indole, which were also obtained from the corresponding pyruvic acid dihydrazones, were synthesized by cyclization of ethyl pyruvate 2,7- and 2,6-naphthylenedihydrazones and subsequent saponification and decarboxylation of the cyclization products. The syn-syn, syn-anti, and anti-anti forms of the dihydrazones were isolated and characterized.See [1] for Communication 19.Translated from Khimiya Geterotsiklcheskikh Soedinenii, No. 3, pp. 352–357, March, 1984. 相似文献
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Tolshchina S. G. Vyakhireva A. G. Ignatenko N. K. Ishmetova R. I. Ganebnykh I. N. Slepukhin P. A. Rusinov G. L. 《Russian Chemical Bulletin》2009,58(6):1281-1290
The intramolecular cyclization of (6-R-1,2,4,5-tetrazin-3-yl)hydrazones of ketones (R is 3,5-dimethylpyrazol-1-yl, 4-methylimidazol-1-yl, or 2-alkylidenehydrazino) giving rise to the previously unknown 3,7-dihydro-1,2,4-triazolo[4,3-b]-1,2,4,5-tetrazines, including spiro compounds, was studied. The reactivity and the yields of the reaction products depend on the structure of the alkylidene fragment and the nature of the substituent in the tetrazine ring.
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When dissolved in liquid ammonia 5-chloro-1,2-dihydropyrimido[5,4-e]-1,2,4-triazine ( 1 ) and 5-methoxy-pyrimido[5,4e]-1,2,4-triazine ( 4 ) quickly convert into 5-aminopyrimido[5,4-e]-1,2,4-triazine ( 2 ). When 2 is kept in liquid ammonia containing an excess of potassium permanganate, 3,5-diaminopyrimido[5,4-e]-1,2,4-triazine ( 5 ) is formed. 相似文献
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The new compound 7-methylpyrazolo[4,5-e][1,2,4]thiadiazin-3(2H,4H)-one1,1-dioxide (5) was synthesized and its novel mono N2- or N4-substituted derivatives 6 and 7 were prepared by regioselective N-alkylation of 5 with different molar ratios of NaH and alkyl halides. Based on the regioselective alkylation conditions found a facile one-pot synthesis of N2,N4-disubstituted pyrazolo[4,5-e][1,2,4] thiadiazines 8 was developed. The structures of the newly synthesized compounds were confirmed by IR,(1)H-NMR, (13)C-NMR and MS spectral analysis. 相似文献
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Iradj Lalezari 《Journal of heterocyclic chemistry》1976,13(6):1249-1251
Substituted 2,5-dihydro-3[3-methyI(or phenyl)-5-aminopyrazolyl]-1,2,4-triazin-5-ones reacted with orthoesters to yield exclusively 1,2,4-triazino[2,3-e]pyrazolo[1,5-a]-1,3,5-triazin-5-ones. The structure elucidation was supported by independent synthesis of the isomeric 1,2,3-triazino-[4,3-e]pyrazolo[1,5-α]-1,3,5-triazin-7-one as well as by spectroscopical methods. 相似文献
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Maria Rosaria Del Giudice Anna Borioni Carlo Mustazza Franco Gatta 《Journal of heterocyclic chemistry》1994,31(6):1503-1507
A number of 2-aryl-substituted pyrido[3,2-e] and [4,3-e][1,2,4]triazolo[1,5-c]pyrimidines and [1,2,4]triazolo[1,5-c]pteridines 11,12a,b,e , their corresponding 5-carbonyl derivatives 7,8a,b,e and some pyrimido[5,4-e][1,2,4]triazolo[1,5-c]pyrimidin-5-ones 7,8c,d have been synthesized, according to different pathways. The new tricyclic heterocycles were prepared with the aim of studying their possible benzodiazepine receptors affinity. 相似文献
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A. Monge Vega I. Aldana M. M. Rabbani E. Fernandez-Alvarez 《Journal of heterocyclic chemistry》1980,17(1):77-80
This paper describes the synthesis of the previously unknown 11H-1,2,4-triazolo[4,3-b]pyridazino[4,5-b]indoles (2) and 11H-tetrazolo[4,5-b]pyridazino[4,5-b]indoles (3) from 4-hydrazino-5H-pyridazino[4,5-b]indoles (1) , as well as the synthesis of 1,2,4-triazolo[3,4-f]-1,2,4-triazino-[4,5-a]indoles (10) from 2-indolecarbohydrazide (4) . Compounds 2 were obtained by acylation of compounds 1 , followed of thermal cyclization and compounds 3 by treating compounds 1 with nitrous acid. The reactions of compound 4 with formic acid or ethyl orthoformiate gave 1,2-dihydro-1-oxo-1,2,4-triazino[4,5-a]indole (6) . Treating this last compound with phosphorus oxychloride or phosphorus pentasulfide, followed by hydrazine, gave 1-hydrazino-1,2,4-triazino-[4,5-a]indole (9) . Acylation of this last compound, followed of cyclization gave compounds 10 . All the compounds were characterized by elemental analysis and ir and 1H-nmr spectra. 相似文献
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The hydrochlorides of the title compounds are obtained in moderate yields by refluxing 2-chloro-3-aminopyridine or 3-amino-4-chloropyridine, respectively, with an alkyl. Aralkyl-, or aryl isothiocyanate in absolute ethanol solution. A proof is presented that the 2-aminothiazolopyridine hydrochloride and not the isomeric o-chloropyridylthiourea is the product of this reaction. The free-bases may be obtained from the hydrochlorides with aqueous sodium bicarbonate. A mechanism for the formation of the thiazole ring is briefly considered. The interactions of 2-chloro-3-aminopyridine with l-substituted-5-mereapto-1H-tetrazoles are also described. 相似文献
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A. A. Karapetyan M. S. Aleksanyan A. Sh. Oganisyan A. S. Noravyan Yu. T. Struchkov 《Journal of Structural Chemistry》1994,35(5):747-749
Institute of Fine Organic Chemistry, Armenian Academy of Sciences. A. N. Nesmeyanov Institute of Organoelement Compounds,
Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 5, pp. 197–199, September–October, 1994. 相似文献