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1.
I. Strakova M. Petrova S. Belyakov A. Strakovs 《Chemistry of Heterocyclic Compounds》2003,39(12):1608-1616
The interaction of 3-formyl-4-coumarin with arylhydrazine hydrochlorides in the presence of sodium acetate gave the corresponding 3-arylhydrazonomethyl-4-chlorocoumarin, and with phenylhydrazine, 4-bromo- and 4-chlorophenylhydrazine hydrochlorides in the presence of two equivalents of triethylamine gave either 1-aryl- or 2-aryl[1]benzopyrano[4,3-c]pyrazol-4-ones depending on the reaction conditions. In reactions of 4-chloro-3-formylcoumarin with 2,4-dichloro-, 2,4-difluoro-, 2-hydroycarbonyl-, 4-nitro- and 3,5-di(trifluoromethyl)phenylhydrazine, 2-pyridyl- and 2-quinoxalylhydrazine in the presence of excess of triethylamine the 2-aryl[1]benzopyrano[4,3-c]pyrazol-4(2H)-ones were obtained exclusively. The structures of 1-phenyl- and 2-(2-pyridyl)[1]benzopyrano[4,3-c]pyrazolo-4(1H)ones were confirmed by X-ray crystallography. A simple method is proposed to distinguish between 1- and 2-substituted [1]benzopyrano[4,3-c]pyrazolo-4-ones on the basis of the 1H NMR chemical shifts of the C(3)-H proton in two solvents - DMSO-d6 and CDCl3. 相似文献
2.
The Pechmann reaction of 4-hydroxycoumarins with cyclohexanone and ethyl cyclopentanone-2-carboxylates affords 1,2,3,4-tetrahydro[2]benzopyrano[4,3-c][1]benzopyran-5,12-diones and cyclopenta[3′,4′]pyrano-[3,2-c][1]benzopyran-4,11-diones. Dehydrogenation of the former yields [2]benzopyrano[4,3-c][1]benzopyran-5,12-diones. Alkaline hydrolysis of a typical compound Va affords 2-hydroxy-2′-carboxydeoxybenzoin which on boiling with acetic anhydride gives an isocoumarin derivative. 相似文献
3.
R. A. Nadzhafova 《Russian Journal of Organic Chemistry》2002,38(1):126-128
Ethyl 6-alkyl(aryl)-4-chloromethyl-2-methylpyridine-3-carboxylates react with ammonia andprimary amines to give 6-substituted 3-alkyl(aryl)-1-methyl-1'2-dihydropyrrolo[3'4-c]pyridin-7-ones.The reactions with 4-aminopyridine yield ethyl 6-alkyl(aryl)-2-methyl-4-(4-pyridylaminomethyl)pyridine-3-carboxylates. 相似文献
4.
The reactions of aroylacetonitriles with the nickel chelate of ethyl acetoacetate afforded new block heterocyclic reagents, viz., 3-acetyl-4-amino-6-arylpyran-2-ones. The reactions of the latter with diethyl oxalate gave rise to ethyl 7-aryl-4,5(1H,5H)-dioxopyrano[4,3-b]pyridine-2-carboxylates. 相似文献
5.
Sodium m-nitrobenzene sulfonate, widely used in dehydrogenation of 4,5-dihydro-3(2H)-pyridazinones to their corresponding aromatic derivatives, behaves in an unexpected way when 4,4a-dihydro-5H[1]benzopyrano[4,3-c]pyridazin-3(2H)-ones are employed as substrate. The synthesis of a new class of 5-hydroxy[1]benzopyrano[4,3-c]pyridazin-3(2H)-ones is described. 相似文献
6.
R. I. Vas’kevich P. V. Savitskii E. B. Rusanov V. I. Staninets 《Russian Journal of Organic Chemistry》2010,46(11):1682-1686
1-(6-Methyl-5-oxo-2,5-dihydro-1,2,4-triazin-3-yl)-4-arylthiosemicarbazides treated with methyl iodide in the presence of sodium
acetate in ethanol convert into 6-methyl-3-arylamino[1,2,4]-triazolo[4,3-b][1,2,4]triazin-7(1H)-ones. In reaction with dicyclohexylcarbodiimide 6-methyl-3-arylamino[1,2,4]triazolo[3,4-c][1,2,4]triazin-5(1H)-ones were obtained which at heating in alcohol solution in the presence of sodium acetate or at 262–272°C underwent the
Dimroth rearrangement to give 3-methyl-7-arylamino[1,2,4]triazolo[5,1-c][1,2,4]-triazin-4(8H)-ones. 相似文献
7.
《Mendeleev Communications》2022,32(4):454-456
Novel 4-oxo-4H-furo[3,2-c]pyran-3-carboxylates and 4-oxo- 4H-furo[3,2-c]chromene-3-carboxylates were prepared from available alkyl 3-bromo-3-nitroacrylates and 4-hydroxy-6- methyl-2H-pyran-2-one or 4-hydroxycoumarin, respectively. Their structures were confirmed by NMR and X-ray data. 相似文献
8.
R. Vaickelioniene V. Mickevicius G. Mikulskiene 《Chemistry of Heterocyclic Compounds》2004,40(6):767-775
We have studied condensation of 1-(4-bromophenyl- and 2,5-dimethylphenyl)-3-ethoxycarbonyl-2-methyl-1,4,5,6-tetrahydro-4(1H)pyridones with hydrazine, phenylhydrazine, and hydroxylamine, as a result of which we obtained nucleophilic substitution and intramolecular cyclization products: 5-(4-bromophenyl- and 2,5-dimethylphenyl)-4-methyl-2,5,6,7-tetrahydro-3H-pyrazole[4,3-c]pyridin-3-ones, 5-(4-bromophenyl- and 2,5-dimethylphenyl)-4-methyl-6,7-dihydroisoxazole[4,3-c]pyridin-3(5H)-ones. We used computer modeling of the molecules of the studied compounds to obtain additional information on the structural features of the reaction products. 相似文献
9.
A. N. Vasil’ev A. N. Lyshchikov O. E. Nasakin Ya. S. Kayukov V. A. Tafeenko 《Russian Journal of Organic Chemistry》2005,41(2):279-282
Reduction of alkyl-2-amino-5,6-dialkyl-3-cyanopyridine-4-carboxylates with sodium borohydride in protic solvents gave rise to 4-amino-3-imino-6,7-dialkyl-1,3-dihydrofuro[3,4-c]pyridines that at hydrolysis in acid medium afforded the corresponding lactones.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 2, 2005, pp. 288–291.Original Russian Text Copyright © 2005 by Vasil’ev, Lyshchikov, Nasakin, Kayukov, Tafeenko. 相似文献
10.
Renata Toplak Jurij Svete Branko Stanovnik Simona Goli Grdadolnik 《Journal of heterocyclic chemistry》1999,36(1):225-235
Methyl 2-(benzyloxycarbonyl)aimno-3-dimemylaminopropenoate ( 2 ) was prepared from methyl N-(benzyloxycarbonyl)glycinate ( 1 ) and t-butoxybis(dimethylamino)methane, and used as a reagent for preparation of substituted 3-(benzyloxycarbonyl)amino-4H-quinolizin-4-ones 5 and 6 , ?2H-pyran-2-ones 17–19 , ?2H-1-benzopyran-2-ones 28–31 , and -naphthopyrans 32–35 , ?2H-pyrano[3,2-c]pyridine-2,5-dione 46 , -pyrano-[4,3-b]pyran-2,5-dione 47 , -pyrano[3,2-c]benzopyran-2,5-dione 48 , -pyrano[2,3-c]pyrazol-6-ones 49 and 50 , -pyrano[2,3-d]pyrirnidin-7-ones 51 and 52 derivatives. In the reaction of 2 with 1,3-diketones trisubsti tuted pyrroles 14–16 were formed. Selective removal of benzyloxycarbonyl group was achieved by cat alytic transfer hydrogenation with Pd/C in the presence of cyclohexene to afford free 3-amino compounds 7 , 8 , 20 , 36–38 and 53–57 in yields better than 80%. 相似文献
11.
A. N. Vasiliev Ya. S. Kayukov O. E. Nasakin A. N. Lyshchikov V. N. Nesterov O. V. Kayukova O. V. Poulkherovskaya 《Chemistry of Heterocyclic Compounds》2001,37(3):309-314
An unusual route has been found for the hydrolysis of 3-amino-1,1-dialkoxy-6,7-dialkyl-4-aryl-3a,4,5,7a-tetrahydro-1H-pyrrolo[3,4-c]pyridine-3a,7a-dicarbonitriles in acidic medium which leads to the formation of alkyl 5,6-dialkyl-2-amino-3-cyanopyridine-4-carboxylates. 相似文献
12.
A. Krutosikova L. Krystofova-Labudova M. Dandarova 《Chemistry of Heterocyclic Compounds》2001,37(12):1511-1517
Methyl 4-oxiranylmethyl-4H-furo[3,2-b]pyrrole-5-carboxylates 2a-c and methyl 1-oxiranylmethyl-1H-benzo[4,5]furo[3,2-b]pyrrole-2-carboxylate (2d) were prepared by reaction of the appropriate starting compounds 1a-d with excess chloromethyloxirane. The compounds 2a-d undergo oxirane ring opening by heterocyclic amines (morpholine, pyrrolidine, piperidine or 4-methylpiperazine) giving N-2-hydroxy-3-heteroaminopropyl-substituted compounds 3a-f or substituted 4,5-dihydrofuro[2',3':4,5]pyrrolo[2,1-c][1,4]oxazin-8-ones 4a-e. 相似文献
13.
A. N. Vasiliev A. N. Lyshchikov O. E. Nasakin Ya. S. Kayukov 《Chemistry of Heterocyclic Compounds》2004,40(4):460-464
An unusual direction has been found for the interaction of alkyl 5,6-dialkyl-2-amino-3-cyanopyridine-4-carboxylates with primary amines leading to the formation of 2,6,7-trialkyl-4-amino-2,3-dihydro-1H-pyrrolo[3,4-c]pyridine-1,3-diones. 相似文献
14.
Prof. Dr. Fritz Sauter Peter Stanetty Hans Potužak Morteza Baradar 《Monatshefte für Chemie / Chemical Monthly》1976,107(3):669-673
The title substances1 and2 were prepared by acylation of the corresponding ethyl 2-amino-thiophene- (or:-4,5,6,7-tetrahydro-benzo[b]thiophene)-3-carboxylates, in some cases followed by reactions introducing a basic substituent.Additionally a group of 2-aroylamino-thiophene-(or:-4,5,6,7-tetrahydro-benzo[b]thiophene)-3-carboxamides was subjected to ring closure reactions, yielding the corresponding 2-aryl-thieno[2,3-d]pyrimidin-4(3H)-ones and 2-aryl-[1]benzothieno[2,3-d]pyrimidin-4(3H)-ones (both:3).
Zum Teil unter Mitarbeit vonFerdinand Fuhrmann 相似文献
Zum Teil unter Mitarbeit vonFerdinand Fuhrmann 相似文献
15.
Unprecedented cyclization was observed during N-sulfonylation of 3-[1-(phenylhydrazono)-ethyl]-chromen-2-one in pyridine, affording 3-methyl-1-phenylchromeno[4,3-c]pyrazol-4(1H)-ones. To avoid use of noxious pyridine, reaction was tried in different basic conditions and the best results were obtained with potassium carbonate in acetone. A wide range of substrates bearing either electron-donating or electron-withdrawing substituents on phenylhydrazine ring were compatible with the developed methodology. Rapid access of starting material, 3-acetylcoumarin, excellent yields of products, and use of environmentally benign base and solvent for the cyclization make this strategy an efficient and convenient method for synthesis of 3-methyl-1-phenylchromeno[4,3-c]pyrazol-4(1H)-ones. 相似文献
16.
Reaction of 2-alkylthio-6-aminopyrimidin-4(3H)-ones with ethyl bromopyruvate to give ethyl 2-alkyl-thio-4-aminofuro[2,3-d]pyrimidine-5-carboxylates has been shown to proceed under neutral or acidic conditions. The obtained furo[2,3-d]pyrimidines underwent further cyclocondensation reaction with ethyl bromopyruvate to afford diethyl 5-alkylthiofuro[3,2-e]imidazo[1,2-c]pyrimidine-2,9-dicarboxy-lates.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 440–443, March, 2009. 相似文献
17.
Jin-Jun Wang Bing-Zhu Yin Gui-Ji Jiang Kimiaki Imafuku 《Journal of heterocyclic chemistry》1990,27(5):1181-1184
Unsubstituted 5 , and 2-aryl- 6a-c , or 2-(2-benzothiazolyl)-substituted 1,3-dihydroisochromano[4,3-c]pyrazol-3(2H)-ones 7a-f were prepared by the reactions of 3-ethoxyoxalyl- 2 , or 3-ethoxycarbonylisochroman-4-one 3 with hydrazine derivatives. The reactions with amidines gave 2-substituted 4-hydroxyisochromano[4,3-d]-pyrimidines 8a-c . 相似文献
18.
The triethylamine-catalyzed reaction of 4-substituted ethyl 2-acyl-3-amino-6-methylthieno[2,3-b]pyridine-4-carboxylates IIIa-h with 2,2,6-trimethyl-4H-1,3-dioxin-4-one IV gave 4-substituted ethyl 3-acetyl-2-hydroxy-7-methylthieno[2,3-b:4,5-b′]dipyridine-9-carboxylates Va-h. Some of the thienodipyridines ( V ) reacted with excess IV to give 5-substituted ethyl 3-acetyl-4,8-dimethyl-2-oxo-2H-pyrano[2,3-b]-pyrido[3′,2′:4,5]thieno[2,3-e]pyridine-10-carboxylates VI . 相似文献
19.
The structure of 2-amino-3-carbamoylchromone has been studied by 1D and 2D NMR spectroscopy. Selective hydrolysis of this compound gives 3-carbamoyl-4-hydroxycoumarin, whereas the reactions with acetic anhydride and hydrazines, 2-methyl-4H-chromeno-[2,3-d]pyrimidine-4,5(3H)-dione and 3-aminochromeno[4,3-c]pyrazol-4-ones, respectively.
相似文献20.
Reactions of 3-benzenesulfonyloxyalloxazine ( 1a ) and its 1-methyl analog 1b with a number of nucleophilic reagents are reported. Relatively small nucleophiles, such as hydroxide ion, methanol, ethanol, methylamine, hydrazine and hydroxylamine converted 1a to 4-carboxy-s-triazolo[4,3-a]quinoxalin-1(2H)-ones and the corresponding esters or amides. As the size of the amine increased from methylamine to ethylamine, dimethylamine, propylamine and isopropylamine, there were obtained 4-(carboxamido)-s-triazolo[4,3-a]quin-oxalin-1(2H)-ones, (1-carboxamido)imidazolo[4,5-b]quinoxalines and 2,3-bis(ureido)quinoxalines. Sodium hydride or potassium cyanide in hot DMF degraded 1a to imidazolo[4,5-b]quinoxaline. However, methylmer-captide and benzylmercaptide ions attacked the sulfonate group of 1a to form 3-hydroxyalloxazine. 1-Methyl-3-benzenesulfonyloxyalloxazine ( 1b ) reacted with methanol, ethanol, 1-propanol, and to some degree 2-propanol, in the presence of triethylamine to furnish anhydro-1-hydroxy-3-methyl-4-(alkoxycarbonyl)-s-triazolo[4,3-a]quinoxalinium hydroxides. However, sodium methoxide in methanol converted this starting material to a mixture of anhydro-1-hydroxy-3-methyl-s-triazolo[4,3-a]quinoxalinium hydroxide and 1-methyl-3-hydroxyflavazole. A saturated aqueous solution of triethylamine transformed 1b to anhydro-1-hydroxy-3-methyl-s-triazolo[4,3-a]quinoxalinium hydroxide, apparently via the corresponding unstable 4-carboxylic acid. The reactions of 1b with a number of aliphatic amines yielded either amides based on the above mesoionic system or on the 3-carboxamido-2-quinoxalyl semicarbazide structure. The reaction of 1b with potassium cyanide furnished 1-methylimidazolo[4,5-b]quinoxaline. Mechanisms to explain all of the degradations are advanced. 相似文献