4-Hydroxy-2-quinolones 144. Alkyl-, arylalkyl-, and arylamides of 2-hydroxy-4-oxo-4H-pyrido[1,2-<Emphasis Type="Italic">a</Emphasis>]pyrimidine-3-carboxylic acid and their diuretic properties

Alkyl-, arylalkyl-, and arylamides of 2-hydroxy-4-oxo-4H-pyrido[1,2-a]pyrimidine-3-carboxylic acid were prepared with a view to establishing a structure-biological activity relationship. A comparative analysis has been made of their diuretic properties and those of the structurally similar 4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxamides. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 718–729, May, 2008.     

4-Hydroxy-2-quinolones 143. Synthesis,structure, and spectroscopic characteristics of ethyl 2-hydroxy-4-oxo-4H-pyrazino[1,2-<Emphasis Type="Italic">a</Emphasis>]pyrimidine-3-carboxylate

Condensation of aminopyrazine with triethyl methanetricarboxylate gave ethyl 2-hydroxy-4-oxo-4H-pyrazino[1,2-a]pyrimidine-3-carboxylate. According to X-ray analytical data the compound exists in the 2-hydroxy-4-oxo form in the crystal. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 411–419, March, 2008.     

4-hydroxy-2-quinolones. 94. Improved synthesis and structure of 1-hydroxy-3-oxo-5,6-dihydro-3h-pyrrolo[3,2,1-i,j]-quinoline-2-carboxylic acid ethyl ester

A modified method is proposed for preparation and purification, and the special features of the spatial structure have been studied for the ethyl ester of 1-hydroxy-3-oxo-5,6-dihydro-3H-pyrrolo[3,2,1-i,j]-quinoline-2-carboxylic acid. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 718–723, May, 2006.     

4-Hydroxy-2-quinolones 139. Synthesis,structure, and antiviral activity of N-R-amides of 2-hydroxy-4-oxo-4H-pyrido[1,2-<Emphasis Type="Italic">a</Emphasis>]pyrimidine-3-carboxylic acids

Dialkylaminoalkylamides of 2-hydroxy-4-oxo-4H-pyrido[1,2-a]pyrimidine-3-carboxylic acids have been obtained as potential antiviral agents. The special features of the spatial structure of one example of the synthesized compounds have been studied. Results are given of the investigation of cytotoxicity and antiviral activity in relation to type 1 herpes virus and coronavirus. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 61–77, January, 2008.     

Exotic Amino Acids. 6. Synthesis of Substituted 4-Oxo-4H-pyrido[1,2-a]pyrimidines

2-Pyridylaminomethyleneisopropylidenemalonates, prepared from ethoxymethyleneisopropylidenemalonate and 2-aminopyridines, form 4-oxo-4H-pyrido[1,2-a]pyrimidines at their melting points and are separated from the reaction mixture by sublimation.     

4-Hydroxy-2-quinolones. 107. Reaction of triethyl methanetricarboxylate with indoline

The first stage of the reaction of triethyl methanetricarboxylate with indoline is the formation of the diethyl ester of 2-(indoline-1-carbonyl)malonic acid, which then, depending on the conditions selected, may be converted into the ethyl ester of 2-(indoline-1-carbonyl)-3-(indolin-1-yl)-3-oxopropionic acid, methanetri-N-(indolin-1-yl)carboxamide, or the ethyl ester or (indolin-1-yl)amide of 1-hydroxy-3-oxo-5,6-dihydro-3H-pyrrolo[3,2,1-ij]quinoline-2-carboxylic acid. __________ Translated From Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1191–1197, August, 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. 108. N-R-amides of 9-fluoro-1-hydroxy-5-methyl-3-oxo-6,7-dihydro-3H,5H-pyrido[3,2,1-ij]quinoline-2-carboxylic acid and their antitubercular activity

The reaction of 6-fluoro-2-methyl-1,2,3,4-tetrahydroquinoline with triethylmethanetricarboxylate gives di(9-fluoro-1-hydroxy-5-methyl-3-oxo-6,7-dihydro-3H,5H-pyrido[3,2,1-ij]quinolin-2-yl)methane and ethyl 9-fluoro-1-hydroxy-5-methyl-3-oxo-6,7-dihydro-3H,5H-pyrido[3,2,1-ij]quinoline-2-carboxylate from which alkyl-, dialkylaminoalkyl-, and hetarylamides as well as hydrazides were prepared. The structure and antitubercular properties of the compounds synthesized are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1391–1407, September, 2006.     

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 132. Synthesis, chemical, and biological properties of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids 2-nitrobenzylidenehydrazides

1-R-4-Hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids 2-nitrobenzylidenehydrazides are reduced to the corresponding quinoline-3-carboxamides by zinc in glacial acetic acid but in refluxing triethylphosphite they are converted to the symmetrical N,N′-di(4-hydroxy-2-oxo-1,2-dihydro-3-quinolinoyl)hydrazines. A study of the antitubercular activity of the synthetic compounds has been carried out. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1687–1692, November, 2007.     

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 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. 90. Synthesis and antitubercular activity of 4-methyl-2-thiazolylamides of halo-substituted 4-hydroxy-2-oxo-1,2-dihydro-3-quinolinecarboxylic acids

Several variants were studied for the synthesis of esters of halogen derivatives of 4-hydroxy-2-oxo-1,2-dihydro-3-quinolinecarboxylic acids, whose reaction with 2-amino-4-methylthiazole gives the corresponding hetarylamides. Results are given for a study of the antitubercular activity of these products. Communication 89, see ref. [1]. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 71–76, January, 2006.     

4-hydroxy-2-quinolones 151. Reaction of 4-chloro-3-ethoxycarbonyl-2-oxo-1,2-dihydroquinolines with p-toluenesulfonylhydrazide

The reaction of ethyl 4-chloro-1-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylate with p-toluene-sulfonylhydrazide at room temperature in the system DMSO/K₂CO₃ gives 5-methyl-2-(toluene-4-sulfonyl)-1,2-dihydro-5H-pyrazolo[4,3-c]quinoline-3,4-dione, alkylation of which using ethyl iodide gives the 1N-substituted derivative. For Communication 150 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 59-66, January, 2009.     

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. 118. Synthesis,structure, and chemical properties of 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo-[3,2-<Emphasis Type="Italic">a</Emphasis>]quinoline-4-carboxylic acid and its ethyl ester

Bromination of N-allyl-substituted 4-hydroxy-2-quinolinones with molecular bromine in acetic acid or carbon tetrachloride occurs with closing of a five membered oxazole ring to give 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 736–749, May, 2007.     

4-hydroxy-2-quinolones. 124. Synthesis and structure of ethyl 2-bromomethyl-5-oxo-1,2,6,7,8,9-hexahydro-5H-oxazolo-[3,2-<Emphasis Type="Italic">a</Emphasis>]quinoline-4-carboxylate

The hydrogenation of the benzene part of the molecule in N-allyl-substituted 4-hydroxy-2-quinolinones does not affect the nature of their bromination by molecular bromine and gives 2-bromomethyl-5-oxo-1,2,6,7,8,9-hexahydro-5H-oxazolo[3,2-a]quinolines. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1180–1188, August, 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. 96. Synthesis and properties of 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid

Alkaline hydrolysis of the ethyl ester of 4-(cyanoethoxycarbonylmethyl)-2-oxo-1,2-dihydroquinoline-3-carboxylic acid is accompanied by decarboxylation with loss of two molecules of CO₂ and leads to 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 887–893, June, 2006.     

Synthesis of 5-Phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridines

Syntheses are reported for a series of 2-alkylamino-6-phenyl-4-trifluoromethylpyridines. The reaction of 3-cyano-2-(hydroxyalkylamino)-6-phenyl-4-trifluoromethylpyridines with thionyl chloride gave the corresponding 2-(chloroalkylamino)pyridines, 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydro-imidazo[1,2-a]pyridines, and 9-cyano-6-phenyl-8-trifluoromethyl-2,3,4-trihydropyrido[1,2-a]-pyrimidines. X-ray diffraction structural analysis was used to study 8-cyano-5-phenyl-7-trifluoromethyl-2,3-dihydroimidazo[1,2-a]pyridine.