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1.
We have obtained 4-alkyl-6-amino-5-cyano-3-methyl(propyl, phenyl)-2H,4H-pyrano[2,3-c]pyrazoles by reaction of 4-alkylmethylene-3-substituted 5-pyrazolones with malononitrile or cyanothioacetamide. We have used X-ray diffraction to study the structure of 6-amino-5-cyano-4-isopropyl(hexyl)-3-phenyl-2H,4H-pyrano[2,3-c]pyrazoles. 相似文献
2.
Shestopalov AM Emeliyanova YM Shestopalov AA Rodinovskaya LA Niazimbetova ZI Evans DH 《Organic letters》2002,4(3):423-425
Three-component condensation of 4-piperidinones (7), 5-pyrazolones (8), and malononitrile (4) proceeds chemically and electrochemically and is a convenient one-step means of synthesis of substituted 6-amino-5-cyanospiro-4-(piperidine-4')-2H,4H-dihydropyrazolo[3,4-b]pyrans (12). The electrochemical reactions proceed under milder conditions and with yields 12-15% greater than those of the reactions catalyzed by chemical bases. 相似文献
3.
L. G. Sharanina V. K. Promonenkov V. P. Marshtupa A. V. Pashchenko V. V. Puzanova Yu. A. Sharanin N. A. Klyuev L. F. Gusev A. P. Gnatusina 《Chemistry of Heterocyclic Compounds》1982,18(6):607-611
The reaction of 3-methyl-1-phenyl-5-pyrazolene with arylideneamino nitriles in alcohol leads to the formation of 3-methyl-4(1-aryl-2,2-dicyanoethyl)-5-pyrazolones, which are readily cyclized in the presence of bases to the corresponding 6-amino-5-cyano-3-methyl-4-aryl- 1H,4H-pyrazolo[3,4-b]pyrans. The structures of the intermediate and final products were confirmed by the IR, UV, PMR, and mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 801–806, June, 1982. 相似文献
4.
Rodinovskaya L. A. Gromova A. V. Shestopalov A. M. Nesterov V. N. 《Russian Chemical Bulletin》2003,52(10):2207-2213
Substituted 3-hydroxypyrazoles, which were prepared based on ethyl esters of substituted 4-(pyridin-2-ylthio)- or 4-(1,4-dihydropyridin-2-ylthio)acetoacetic acids and hydrazine hydrate, were used in the synthesis of 6-amino-4-aryl-5-cyano-3-(pyridin-2-ylthiomethyl)-2,4-dihydropyrano[2,3-c]pyrazoles. The molecular and crystal structure of 6-amino-5-cyano-3-(3-cyano-4,6-dimethylpyridin-2-ylthiomethyl)-4-(2-nitrophenyl)-2,4-dihydropyrano[2,3-c]pyrazole was established by X-ray diffraction analysis. 相似文献
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A. Sh. Oganisyan G. O. Grigoryan A. S. Noravyan 《Chemistry of Heterocyclic Compounds》2001,37(8):1025-1028
Reaction of a substituted 2-aminothienothiopyran with methyl(phenyl) isothiocyanate, intramolecular cyclization of the obtained N'-methyl(phenyl) thioureido derivatives, and work up of the cyclization products with hydrazine hydrate gave 2-hydrazinodihydrothiopyranothienopyrimidines. Treatment of the latter with pyruvic acid gave the novel 10H-thiopyrano[4',3':4',5']thieno[2',3':4,5]pyrimido[2,3-c]-1,2,4-triazines. 相似文献
7.
Maria Teresa Cocco Cenzo Congiu Antonio Maccioni 《Journal of heterocyclic chemistry》1990,27(3):683-686
The reactivity of acetamidrazones I in strong basicity conditions was examined. When compounds I are reacted with equivalent quantities of α-haloketones in sodium alcoholate, the pyrrolidino[2,3-c]pyrazol-3-ones IV were obtained by intermediate formation of 1-acyl-3-amino-5-pyrazolones III . 相似文献
8.
Derivatives of the 5H-thiazolo[3,2-b]- and 2H-thiazolo[2,3-c]-as-triazine systems were synthesized via condensation of tetrahydro-I-methyl-as-triazine-3(2H)-thione with ethylene dibromide and ethyl bromoacetate, respectively. An hypothesis is given for the formation of the [3,2-b] system in one of these reactions and the [2,3-c] system in the other. Structure proof was accomplished by an unequivocal synthesis of one of the [2,3-c] derivatives. 相似文献
9.
By the reaction of 4-dimethylaminomethylene-3-methyl-1-phenylpyrazol-5-one (3) with methylene compounds like malonodinitrile, cyanoacetamide and alkyl cyanoacetate a number of different substituted title compounds may be prepared. The mechanism of this reaction is illucidated by isolation of the intermediate ethenyl compounds7, 8, 11, 14 and16. The reaction therefore is best described as a sequence of addition, elimination and cyclisation with partial hydrolysis.
6. Mitt.:H.-H. Otto undO. Rinus, Arch Pharm. (Weinheim)312, 548 (1979). 相似文献
10.
Shunsaku Shiotani Katsunori Taniguchi Toshimasa Ishida Yasuko In 《Journal of heterocyclic chemistry》1996,33(3):647-654
Acetoxylation of N-oxide of furo[2,3-b]- 2a , -[3,2-b]- 2b , -[2,3-c]- 2c and -[3,2-c]pyridine 2d with acetic anhydride afforded compounds substituted normally at the α- or γ-position to the ring nitrogen, 3a, 4a, 4b, 3d, 4d, 8 and 9 , and in addition compounds substituted on the furan ring, 5a, 6a, 5b, 6b, 7b, 5c and 7c which were unexpected compounds. The structures of these compounds were established from the ir, nmr and mass spectra, and x-ray crystal analysis of 5b . 相似文献
11.
A. M. Kamal El-Dean M. S. A. El-Gaby A. M. Gaber H. A. Eyada A. S. N. Al-Kamali 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):413-424
Abstract Novel series of thieno[2,3-c]pyridazines and pyrimido[4′,5′:4,5] thieno-[2,3-c]pyridazines have been synthesized from the readily accessible 4-cyano-5,6-dimethylpyridazin-3(2H)-thione 3b. 相似文献
12.
Misbahul Ain Khan Alina Guerra Cosenza Gwynn Pennant Ellis 《Journal of heterocyclic chemistry》1982,19(5):1077-1085
Various 1H,6H-pyrano[2,3-c]pyrazol-6-ones (III-XXIII) were obtained from β-keto esters and 1H-pyrazol-5-ones or hydrazines. Nitrations, chlorinations and brominations of these pyranopyrazoles were also carried out giving the corresponding derivatives (XXIV-LXIV). The pyrone ring is the more reactive one in these reactions and the preferred position of attack is the 5-position. The substitution products are formed by the addition-elimination route. 相似文献
13.
Irina O. Zhuravel Oleg V. Zaremba Oleksandr S. Detistov Svitlana S. Kovalenko Valentin P. Chernykh 《合成通讯》2013,43(21):3778-3784
New 5-hydroxymethyl-8-methyl-3-(3-aryl-[1,2,4]oxadiazol-5-yl)-2H-pyrano-[2,3-c]pyridin-2-ones and their esters were synthesized. The structure of obtained compounds was determined through a complete 1H NMR analysis. 相似文献
14.
Chlorination of the N-oxides of furo[2,3-b]- 1a , -[2,3-c]- 1b and -[3,2-c]pyridine 1c with phosphorus oxychloride afforded compounds substituted normally at the α- or λ-position to the ring nitrogen, 2a, 2′a, 2b, 2c, 2′c and 2′c , and in addition, in the case of 1b , compounds substituted on the furan ring, 2′b and 2″b . The structures of these compounds were confirmed from their ir, nmr and mass spectra. The major chlorinated products 2a, 2b and 2c were converted to methoxy- 5a, 5b and 5c , N-pyrrolidyl- 7a, 7b and 7c , and phenylthiofuropyridines 8a, 8b , and 8c . 相似文献
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V. D. Dyachenko 《Russian Journal of General Chemistry》2005,75(3):447-456
The condensation of enamines derived from acetoacetanilides, heterocyclic aldehydes, and cyanothioacetamide yielded ammonium 5-arylcarbamoyl-5-heteryl-6-methyl-3-cyano-1,4-dihydropyridine-2-thiolates, which were subsequently used for the synthesis of substituted 2-alkylthio-1,4-dihydropyridines, 2-alkylthiopyridines, and thieno[2,3-b]pyridines. The reaction of acetoacetamide with heteroaromatic aldehydes and cyanoselenoacetamide in the presence of N-ethylmorpholine yielded N-ethylmorpholinium 4-heteryl-5-carbamoyl-6-methyl-3-cyano-1,4-dihydrolyridine-2-selenolates, from which substituted 2-alkylseleno-1,4-dihydropyridines were prepared.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 483–492.Original Russian Text Copyright © 2005 by Dyachenko. 相似文献
18.
This paper describes reactions of 3-bromo- 1a-d , 2-phenylthio- 5a-d and 2-phenylthio-3-bromofuropyridines 6a-d with n-butyl-, t-butyl- and methyllithium and lithioacetonitrile. Lithiation of compounds 1a-d with n-butyl- or methyllithium gave the parent furopyridines 2a-d and o-ethynylpyridinols 3a-d. Reaction of compounds 5a-d with methyllithium afforded o-(phenylthioethynyl)pyridinols 7a-d , which were also yielded by reaction of compounds 6a-d with t-butyl- or methyllithium. The phenylthio group in compounds 7a-d were substituted with t-butyl group by the reaction with excess t-butyllithium. In contrast, 2-phenylthio group in compounds 5a-d and 6a-d was substituted with cyanomethyl group by reaction with lithioacetonitrile to give compounds 11a-d and 10b, c respectively. 相似文献
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20.
Donald L. Trepanier Shyam Sunder Werner H. Braun 《Journal of heterocyclic chemistry》1974,11(5):747-750
This paper describes the reactions of 2-o-aminophenyl-1,4,5,6-tetrahydro-1-methyl-1,2,4-triazine with a variety of reagents to give substituted 1,2,4-triazino[4,3-c]quinazolines or 1,2,4-triazino[2,3-c]quinazolines. Certain representative compounds of these two new heterocyclic systems were characterized by the tlc, ir, nmr, mass spectra, and identified by unequivacol synthesis. 相似文献