共查询到20条相似文献,搜索用时 12 毫秒
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E. N. Ulomskiy N. R. Medvedeva A. V. Shchepochkin O. S. Eltsov V. L. Rusinov O. N. Chupakhin E. G. Deeva O. I. Kiselev 《Chemistry of Heterocyclic Compounds》2011,47(9):1164-1169
The reaction of 3-R-5-amino-1,2,4-triazoles with the ethyl ester of 2-fluoroacetoacetic acid gave 2-R-fluoro[1,2,4]triazolo[1,5-a]pyrimidin-7(4H)-ones. The reaction of a 3-R-1,2,4-triazolyl-5-diazonium salt with the ethyl ester of 2-fluoroacetoacetic acid and subsequent
cyclization of the triazolylhydrazones lead to 7-R-3-fluoro[1,2,4]triazolo[5,1-c][1,2,4]triazin-4(1H)-ones. 相似文献
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V. L. Gein T. M. Zamaraeva N. V. Nosova M. I. Vakhrin P. A. Slepukhin 《Russian Journal of Organic Chemistry》2012,48(3):419-422
Three-component reaction of N-methyl- or N,N-diethyl-3-oxobutanamide with aromatic aldehydes and tetrazol-5-amine monohydrate gave the corresponding N-substituted 7-aryl-5-methyl-4,7-dihydrotetrazolo-[1,5-a]pyrimidine-6-carboxamides. 相似文献
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V. L. Gein I. N. Vladimirov O. V. Fedorova A. A. Kurbatova N. V. Nosova I. V. Krylova M. I. Vakhrin 《Russian Journal of Organic Chemistry》2010,46(5):699-705
Alkyl 5-aryl-7-methyl-1,5-dihydrotetrazolo[1,5-a]pyrimidine-6-carboxylates were obtained by melting acetoacetic acid esters with 5-aminotetrazole and aromatic aldehyde. 相似文献
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V. L. Gein T. M. Zamaraeva O. S. Panova V. D. Belonogova 《Russian Journal of General Chemistry》2015,85(10):2299-2303
Reactions of alkyl aroylpyruvates with a mixture of aromatic aldehyde and 5-aminotetrazole led to the formation of alkyl 7-aryl-6-aroyl-4,7-dihydrotetrazolo [1,5-а] pyrimidine-5-carboxylates. 相似文献
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Mehdi Rimaz Hossein Mousavi Laya Nikpey Behzad Khalili 《Research on Chemical Intermediates》2017,43(7):3925-3937
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Maksim A. Kolosov Elena H. Shvets Dmitriy A. Manuenkov Sergey A. Vlasenko Irina V. Omelchenko Svetlana V. Shishkina Valeriy D. Orlov 《Tetrahedron letters》2017,58(12):1207-1210
6-Unsubstituted 7-R-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidines (R = H or Me) were synthesized via two pathways: (a) deacylation of the corresponding 5-acetyl Biginelli-like precursors in KOH/H2O and (b) reduction of the corresponding 1,2,4-triazolo[1,5-a]pyrimidines using LiAlH4. The products could be easily formylated at position 6, which is promising for the further synthesis of functionalized 6-substituted derivatives of 4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidines. In contrast, 6-acetyl-7-(4-(N,N-dimethylaminophenyl))-5-methyl-4,7-dihydro-1,2,4-triazolo[1,5-a]pyrimidine undergoes a cascade process in KOH/H2O, leading to the formation of a 4,5,8,9-tetrahydro[1,2,4]triazolo[5,1-b]quinazoline derivative. 相似文献
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V. L. Gein L. F. Gein E. P. Tsyplyakova O. S. Panova 《Russian Journal of Organic Chemistry》2007,43(9):1382-1386
6-Acyl-7-aryl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-5-carboxylic acids and methyl 6-acyl-7-aryl-4,7-dihydrotetrazolo[1,5-a]pyrimidine-5-carboxylates were synthesized by fusion of 4-aryl-2,4-dioxobutanoic acids and their methyl esters, respectively, with 1H-tetrazol-5-amine and aromatic aldehydes. The reaction of methyl 2,4-dioxopentanoate with 1H-tetrazol-5-amine and 2-fluorobenzaldehyde in boiling acetic acid gave methyl 6-acetyl-5-hydroxy-7-(2-fluorophenyl)-4,5,6,7-tetrahydrotetrazolo[1,5-a]pyrimidine-5-carboxylate. 相似文献
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Sergey M. Desenko Sergey A. Komykhov Valery D. Orlov Herbert Meier 《Journal of heterocyclic chemistry》1998,35(4):989-990
The cyclocondensation of 6-acetyl-4,7-dihydro-5-methyl-7-phenyl[1,2,4]triazolo[1,5-a]pyrimidine (3) with hydroxylamine or hydrazine leads to 3a,4,9,9a-tetrahydro-3,9a-dimethyl-4-phenylisoxazolo-[5,4-d][1,2,4]triazolo[1,5-a]pyrimidine ( 4a ) and 3a,4,9,9a-tetrahydro-3,9a-dimethyl-4-phenyl-1H-pyrazolo[3,4-d][1,2,4]triazolo[1,5-a]pyrimidine ( 4b ), respectively. In the presence of methanolic hydrogen chloride, 4b undergoes a cleavage of the pyrimidine ring to yield (5-amino-1,2,4-triazol-1-yl)(3,5-dimethylpyrazol-4-yl)phenylmethane ( 5 ). The structure determination of the compounds obtained is based on 1H and 13C nmr spectra including NOE measurements. 相似文献
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Kh. S. Shikhaliev D. V. Kryl’skii A. Yu. Potapov M. Yu. Krysin 《Russian Chemical Bulletin》2005,54(12):2903-2904
Three-component condensation of 3-amino-1,2,4-triazole (or its 5-methyl and 5-methylthio derivatives), dimedone (or cyclohexane-1,3-dione),
and dimethylformamide dimethyl acetal afforded 8,8-R, R-8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin-6(7H)-ones.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 12, pp. 2805–2807, December, 2005. 相似文献