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1.
The structure and tautomerism of 2-amino-3, 6-dimethyl-, and 2-amino-3,6,7-trimethylbenzo[1,2-d: 3,4-d']diimidazoles were studied by means of IR and UV spectroscopy. It was found that they exist in the amino form in the crystalline state and in methanol solution.See [1] for communication III.Translated from Khimiya GeterotsiklicheskikhSoedinenii, No. 6, pp. 807–809, June, 1973 相似文献
2.
Misbahul Ain Khan Alice Maria Coimbra Rolim Antonio Elydio Guaroni 《Journal of heterocyclic chemistry》1983,20(2):475-476
The synthesis of the parent ring system and some of the derivatives of 1H-pyrazolo[3,4-d]thieno[2,3-b]pyridine are described. 相似文献
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Branko Stanovnik Borut Furlan Marko Kupper Lidija Male Anton timac Miha Tiler Marko
li
ar 《Journal of heterocyclic chemistry》1988,25(2):393-398
The nucleophilic and electrophilic substitutions of 6-substituted 9,9-dimethyl-9H-imidazo[1,2-b]pyrazolo- [4,3-d]pyridazines 2 , nucleophilic substitutions of 6-substituted 9,9-dimethyl-9H-pyrazolo[4,3-d]-s-triazolo- [4,3-b]pyridazines 7 and some other transformations to give compounds 3 and 8 , respectively, were studied. It was shown that both heterocyclic systems are stable under the conditions employed in these transformations. 相似文献
4.
S. Tumkyavichyus 《Chemistry of Heterocyclic Compounds》1996,32(6):716-720
The reaction of 4-(amino-substituted)-2-methylthio-6-chloropyrimidine-5-carbonitriles with hydrazine and methylhydrazine was used to synthesize 3, 4-diamino-6-methylthio-1H-pyrazolo[3, 4-d]pyrimidines. It was shown that the formation of pyrazolopyrimidines proceeds through intermediate 6-hydrazinopyrimidine-5-carbonitriles.Department of Organic Chemistry, Vil'nyus University, Vil'nyus 2006. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 831–836, June, 1996. Original article submitted February 9, 1996. 相似文献
5.
A simple and efficient synthesis of pyrazolo[3,4-b] quinolines is described. The synthesis involves reaction of 2-amino-3-cyanoquinoline-4-carboxylates(1) with hydrazine hydrate to give regioselectively only pyrazolo[3,4-b]quinolines (2). No formation of pyridazino quinolines (3) is observed. 相似文献
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The synthesis of a number of new 1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid derivatives is described. Most of these compounds have either an alkoxy or a basic substituent in position 4. 相似文献
7.
V. M. Dziomko A. V. Ivashchenko O. N. Garicheva L. V. Shmelev Yu. S. Ryabokobylko G. M. Adamova 《Chemistry of Heterocyclic Compounds》1981,17(7):715-719
New 1-(2-pyrimidinyl)-1H-pyrazolo[3,4-b]pyridine derivatives were obtained. The reactivity in reactions involving nucleophilic substitution of the chlorine atom by amino, arylamino, and hydrazino groups was investigated. Data from the IR, UV, and PMR spectra are presented.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 963–967, July, 1981. 相似文献
8.
Smolobochkin A. V. Gazizov A. S. Garifzyanov A. R. Burilov A. R. Pudovik M. A. 《Russian Chemical Bulletin》2022,71(5):878-884
This review covers and summarizes comprehensive data reported within the period from 2017 to 2021 on the synthetic strategies and approaches to 1H-pyrazolo[3,4-b]pyridine derivatives. Methods for the synthesis are systematized according to the method to assemble the pyrazolopyridine system, whereas their advantages and drawbacks are considered.
相似文献9.
Silvio Massa Antonello Mai Marino Artico Federico Corelli 《Journal of heterocyclic chemistry》1990,27(6):1805-1808
Cyclization of pyrrolidinocarboxamide derivatives of 1-phenyl-5-(1H-pyrrol-1-yl)-1H-pyrazole-4-carboxylic acid and 2-phenyl-3-(1H-pyrrol-1-yl)-1H-pyrazole-4-carboxylic acid afforded imminium salts which were transformed into the corresponding ketones. Further reduction of the latter compounds furnished the title derivatives. 相似文献
10.
E. S. Komarova V. A. Makarov L. M. Alekseeva G. V. Avramenko V. G. Granik 《Russian Chemical Bulletin》2006,55(4):735-740
1-[4-Aminoarylpyrazolo[3,4-b]pyridin-5-yl]pyridinium chlorides undergo cyclization under reflux in tert-butanol in the presence of an excess of potassium tert-butoxide to form tetracyclic derivatives of pyrazolo[3,4-b]pyrido[1′,2′:1,2]imidazo[4,5-d]pyridine. The reaction scheme of the processes is proposed. The structures of the reaction products were confirmed by physicochemical
methods.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 710–714, April, 2006. 相似文献
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G. Kh. Khisamutdinov V. L. Korolev T. N. Parkhomenko V. M. Sharonova E. S. Artem'eva I. Sh. Abdrakhmanov S. P. Smirnov B. I. Ugrak 《Russian Chemical Bulletin》1993,42(10):1700-1702
New methods for the synthesis of 1,2,4-triazolo[4,3-d]-1,2,4-triazolo[3,4-f]furazano[3,4-b]pyrazines with functional substituents of various types are proposed and some properties of these compounds are studied.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 1776–1778, October, 1993. 相似文献
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15.
Ahmad Sami Shawali 《Journal of heterocyclic chemistry》1977,14(3):375-381
A number of substituted 2H-pyrazolo[3,4-d]pyridazines, pyridazin-7(6H)ones, and -pyrid-azine-4,7(5H,6H)diones have been prepared from the 3,4-diacyl-, 3-carbethoxy-4-acyl-, 3-carbethoxy-4-cyano-, and 3,4-dicarbethoxy-pyrazole derivatives and hydrazine hydrate. The structures of the compounds prepared were inferred from their elemental analyses and spectral data. On the basis of spectroscopic data it was concluded that pyrazolopyridazinones have the oxo form, whereas the monohydroxymono oxo structure is preferred for pyrazolopyridazine-diones. 相似文献
16.
When equimolar quantities of salicylaldehyde 2 and ethyl 3-amino-2-butenoate 3 or its constituents (ethyl 3-oxobutanoate and ammonia) were refluxed on a steam-bath for 6 hours with a trace of acetic acid, two products, a pentacyclic pyridine dilactone 4 and 3-acetyl coumarin 5 , resulted in 15% and 45% yields, respectively. The structure of 4 was elucidated as 7-methyl[1]benzopyrano[4,3-d][1]benzoxacino[4,3-b]-pyridine-6,16-dione on the basis of its spectral data. The mechanism of its formation has been discussed. The reaction has been extended to three more substituted salicylaldehydes. 相似文献
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A novel efficient synthesis of 2-hetaryl-4-methyl-6-phenyl-6H-pyrazolo[3,4-d]-1,2,3-triazoles was achieved by the reaction of 5-amino-3-methyl-4-nitroso-1-phenyl-1H-pyrazole with heterocyclic amines followed by air oxidation in the presence of cupric acetate. 相似文献