4-Hydroxy-2-quinolones 131. Bromination of 3-allyl-4-hydroxy-2-oxo-1,2-dihydroquinoline

The bromination of 3-allyl-4-hydroxy-2-oxo-1,2-dihydroquinoline by molecular bromine is accompanied by the closure of a five membered furan ring and gives the corresponding 2-bromomethyl-3,9-dihydro-2H-furo[2,3-b]quinolin-4-one. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1677–1686, November, 2007.     

4-Hydroxy-2-quinolones. 111. Simple synthesis of 1-substituted 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acids

A preparative method of obtaining 1-substituted 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acids is proposed. Features of their spatial structure have been studied. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 69–74, January, 2007.     

4-Hydroxy-2-quinolones 19. A new synthesis of 3-Alkyl-2-oxo-4-hydroxyquinolines

3-Alkyl-substituted 2-oxo-4-hydroxyguinolines were obtained in high yields from N,N-di-2-alkoxycarbonylanilides of alkylmalonic acids under conditions of the Dieckmann condensation. Some types of biological activity were found for the compounds synthesized.For Communication 18, see [1].Ukrainian Pharmaceutical Academy, Khar'kov 310002. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 673–678, May, 1994. Original article submitted May 6, 1994.     

4-Hydroxy-2-quinolones. 30 Alkylation of 1H-2-oxo-3-carbethoxy-4-hydroxyquinoline

A study has been made of the alkylation of 1H-2-oxo-3-carbethoxy-4-hydroxyquinoline by alkyl halides in the presence of inorganic bases. New methods for the synthesis of 1-substituted 2-oxo-3-carbethoxy-4-ihydroxyquinolines are examined.For communication 29, see [1].Ukrainian Pharmaceutical Academy, Khar'kov 310002. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1104–1112, August, 1996. Original article submitted June 10, 1996.     

4-Hydroxy-2-quinolones. 31. 3-Amino-ir-2-oxo-4-hydroxyquinolines and their acyl derivatives

Abstarct An alternative method has been developed for preparing and studying the antioxidant activity of 3-acylamino-2-oxo-4-hydroxyquinolones. Results are presented from an investigation of the antithyroid and antimicrobial action of the intermediate 2-oxo-3-(1 pyridinio)quinotin-4-olates and the 3-amino-2-oxo-4-hydroxyquinolines.For communication 30, see [1].Ukrainian Pharmaceutical Academy, Khar'kov 310002. Translated from Khimiya Geterotsklicheskikh Soedinenii, No. 8, pp. 1113–1123, August, 1996. Original article submitted June 10, 1996.     

4-hydroxy-2-quinolones. 109. Alkylation of 4-substituted ethyl 2-oxo-1,2-dihydro-quinoline-3-carboxylates

The alkylation of the ethyl esters of 4-methyl, 4-chloro-, and 4-amino substituted 2-oxo-1,2-dihydroquinoline-3-carboxylic acid by ethyl iodide in the system DMF/K₂CO₃ has been studied. Features of the structure of the starting compounds and their effect on the ratio of the N-and O-alkyl products formed are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1502–1507, October, 2006.     

4-Hydroxy-2-quinolones 130. The reactivity of ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylates

The high reactivity of ethyl 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylates is governed by the simultaneous presence of the 4-OH and 2-C=O groups in the pyridine part of the molecule. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1503–1508, October, 2007.     

4-hydroxy-2-quinolones. 110. Bromination of 1-r-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid anilides

1-R-4-Hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid anilides have been prepared. It has been shown experimentally that these compounds are brominated by molecular bromine in glacial acetic acid at position 4 of the anilide fragment. The antitubercular properties of the compounds synthesized are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1508–1516, October, 2006.     

4-Hydroxy-2-quinolones. 39. Structure of 6-bromo-4-hydroxy-1-isoamyl-2-oxo-3-quinolinecarboxylic acid

S-(–)-1-phenylethylamide of 6-bromo-4-hydroxy-1-isoamyl-2-oxo-3-quinolinecarboxylic acid was synthesized. X-ray diffraction investigation of this product was carried out to determine its absolute configuration.For communication 38, see ref. [1].National Pharmaceutical Academy of Ukraine, 310002 Kharkov, Ukraine Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 64–69, January, 2000.     

4-Hydroxy-2-quinolones 142. 4-Methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid anilides as potential diuretics

A large series of 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid anilides has been prepared as potential diuretic agents. The effect of all of the synthesized compounds on the urinary function of the kidney has been investigated. The appearance of a “structure — diuretic activity” relationship is discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 239–245, February, 2008.     

4-Hydroxy-2-quinolones. 37. Simple synthesis of 1-R-2-oxo-3,4-dihydroxyquinolines

3-Amino-1-R-2-oxo-4-hydroxyquinolines easily undergo acid hydrolysis with formation of the corresponding 1-R-2-oxo-3,4-dihydroxyquinolines. For Communication 36, see [1]. Ukrainian Pharmaceutical Academy, Kharkov 310002. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1542–1544, November, 1997.     

4-Hydroxy-2-quinolones. 1. Efficient method for obtaining 3-alkyl-4-hydroxy-2-quinolones

3-Alkyl-4-hydroxy-2-quinolones were obtained in high yields via the Dieckmann intramolecular condensation of substituted malonic acid ethyl ester 2-carbalkoxyanilides.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1533–1534, November, 1991.     

4-Hydroxy-2-quinolones. 92. Reaction of 1-R-4-chloro-3-ethoxycarbonyl-2-oxo-1,2-dihydroquinolines with anilines

A preparative method is proposed and the synthesis of 4-arylamino-2-oxo-1,2-dihydroquinolines has been effected. An X-ray structural investigation of 4-(4-chlorophenylamino)-2-oxo-1-propyl-1,2-dihydroquinoline-3-carboxylic acid has been carried out enabling the ease of decarboxylating such compounds to be substantiated. Results are given of a study of the anti-inflammatory activity of the synthesized compounds. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 386–395, March, 2006.     

4-Hydroxy-2-quinolones. 152*. 3-acetyl-4-hydroxy-2-oxo-1,2-dihydroquinoline and its biologically active derivatives

A synthesis and study of the spatial structure of 3-acetyl-4-hydroxy-2-oxo-1,2-dihydroquinoline have been carried. 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids [1-(4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)ethylidene]hydrazides were prepared from this compound by two routes. A comparative analysis of the antitubercular properties of the synthesized compounds and of the closely structurally related N,N′-di(1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carbonyl)hydrazines has been performed. *For Communication 151 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 214–222, February, 2009.     

4-Hydroxy-2-quinolones. 3. Synthesis and physicochemical properties of 1-R-3-carbethoxy-4-hydroxy-2-quinolones

1-R-3-Carbethoxy-4-hydroxy-2-quinolones were synthesized by intramolecular cyclization of N-R-2-carbalkoxymalonanilic acids by the Dieckmann reaction. The possibility and advantages of conducting this reaction in aqueous medium were demonstrated. The mutually perpendicular orientation of the heterocyclic and aryl fragments was demonstrated for the 1-phenyl derivative by ESR spectroscopy.See [1] for Communication 2.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 636–639, May, 1992.     

4-Hydroxy-2-quinolones. 97. Simple synthesis of the esters of 4-halo-substituted 2-oxo-1,2-dihydroquinoline-3-carboxylic acids

Short term treatment of 3-ethoxycarbonyl-4-morpholino-2-oxo-1,2-dihydroquinoline with aqueous solutions of hydrohalogen acids leads to the formation of the ethyl esters of 4-halo-substituted 2-oxo-1,2-dihydroquinoline-3-carboxylic acids. Hydrolysis in HF is possible on extended boiling only to the 4-hydroxy derivative. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 1022–1025, July, 2006.     

4-Hydroxy-2-quinolones 119. Reaction of ethyl 1-R-4-chloro-2-oxo-1,2-dihydroquinoline-3-carboxylate with malononitrile

In acid medium ethyl 1-R-4-dicyanomethyl-2-oxo-1,2-dihydroquinoline-3-carboxylates are hydrated in the ketenimine tautomer form exclusively to the corresponding quinolylcyanoacetamides. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 856–863, June, 2007.     

4-Hydroxy-2-quinolinones 128. Bromination of N-allyl-4-hydroxy-2-oxo-1,2-dihydroquinolines and pyridines unsubstituted in position 3

Bromination of N-allyl-4-hydroxy-2-oxo-1,2-dihydroquinoline and N-allyl-5-ethoxycarbonyl-4-hydroxy-6-methyl-2-oxo-1,2-dihydropyridine is accompanied not only by closing of a five membered oxazole ring but also by a second bromination of the 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]-derivatives formed at position 4. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1365–1373, September, 2007.     

4-Hydroxy-2-quinolones 140. Synthesis and diuretic activity of arylalkylamides of 4-methyl-2-oxo-1,2-dihydro-quinoline-3-carboxylic acid

The interaction of 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid with thionyl chloride in oxygen-containing solvents leads to the formation of a significant amount of colored side products, consequently it was proposed the reaction be carried out in carbon tetrachloride. The synthesis of a series of amides was effected by the amidation of the obtained acid chloride with appropriate primary arylalkylamines. Results are presented of a study of the effect of the synthesized compounds on the urine-excreting function of the kidney. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 78–87, January, 2008.     

4-Hydroxy-2-quinolones 120. Synthesis and structure of ethyl 2-hydroxy-4-oxo-4H-pyrido-[1,2-a]pyrimidine-3-carboxylate

An improved method for the preparation and purification of ethyl 2-hydroxy-4-oxo-4H-pyrido[1,2-a]-pyrimidine-3-carboxylates is proposed. According to ¹H and ¹³C NMR spectroscopic data the synthesized compounds exist in DMSO solution in the 2-hydroxy-4-oxo form while in the crystal (at least for the case of the unsubstituted derivative) X-ray analysis shows that it occurs in the bipolar 2,4-dioxo form. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 864–876, June, 2007.