4-hydroxy-2-quinolones. 153*. Synthesis of hetarylamides of 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid

4-Methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid hetarylamides can be prepared by two fundamentally different routes with allowance made for the thermal stability of the starting hetarylamines. * For Communication 152 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 426–432, March, 2009.     

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 171*. Synthesis,isomerism, and antitubercular activity of 1-R-4-hydroxy-2-oxo-1,2-dihydro-quinoline-3-carboxylic acid alkylidenehydrazides

Alkylidenehydrazides have been synthesized by the reaction of 1-R-4-hydroxy-2-oxo-1,2-dihydro-quinoline-3-carboxylic acid hydrazides with lower dialkyl ketones in order to reveal a structure-antitubercular activity relationship. It was shown by ¹H NMR spectroscopy that hydrazones obtained from the unsymmetrical ketone – methyl ethyl ketone – exist primarily in the E-isomer form. It was found that the presence of two aliphatic substituents in the alkylidene fragment of the compounds investigated leads to a marked lowering of antimicobacterial properties.     

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.     

4-hydroxy-2-quinolones. 202*. Synthesis, chemical and biological properties of 4-hydroxy-6,7-dimethoxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid alkylamides

In continuation of the search for potential analgesics amongst 4-hydroxyquinol-2-one derivatives we have proposed and carried out a preparative method of synthesis of 4-hydroxy-6,7-dimethoxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid alkylamides. It has been shown that bromination of 4-hydroxy-6,7-dimethoxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid allylamide using an equivalent of molecular bromine occurs with a conventional addition of the halogen to the allyl double bond and not with halocyclization. The results of the study of the analgesic properties of the compounds prepared are presented.     

4-Hydroxy-2-quinolones. 180*. Synthesis,chemical reactions,and analgesic activity of 1-allyl-4-hydroxy-6,7-dimethoxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid alkylamides

A targeted synthesis was carried out of a series of 1-allyl-4-hydroxy-6,7-dimethoxy-2-oxo-1,2-di-hydroquinoline-3-carboxylic acid alkylamides which show interest for biological study as potential analgesics. It was found that, in the presence of one equivalent of bromine, the compounds indicated undergo halocyclization to the corresponding 2-bromomethyl-7,8-dimethoxy-5-oxo-1,2-dihydro-5H-oxa-zolo[3,2-a]quinoline-4-carboxylic acid alkylamides. However, with an excess of bromine the reaction occurs somewhat differently and concludes with the formation of complexes of bromine with 4-alkyl-carbamoyl-2-bromomethyl-5-hydroxy-7,8-dimethoxy-1,2-dihydrooxazolo[3,2-a]quinolinium ditri- bromides. According to the results of pharmacological screening there are found compounds within the substances discovered with high analgesic activity.     

4-Hydroxy-2-quinolones. 168*. Synthesis,chemical and antitubercular properties of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid pyrazin-2-ylamides

1-R-4-Hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acid pyrazin-2-ylamides have been synthesized as potential antitubercular agents. In contrast to pyrimidin-2-ylamides the compounds prepared are brominated by molecular bromine in glacial acetic acid at position 6 of the quinolone ring rather than in the amide part of the molecule. The 1-N-allyl derivative behaves similarly but undergoes halocyclization to give 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline-4-carboxylic acid pyrazin-2-ylamide. A comparative analysis of the antimycobacterial properties of the synthesized compounds and their isomeric pyrimidin-2-ylamides has been carried out.     

4-Hydroxy-2-quinolones 150*. Efficient synthesis,structure, and biological activities of 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid alkyl amides

A simple and efficient method for preparing 4-methyl-2-oxo-1,2-dihydroquinoline-3-carboxylic acid alkyl amides is proposed. The results of a study of the diuretic activity of the compounds synthesized are reported. *For communication 149 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1841-1848, December, 2008.     

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 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. 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. 154*. Pyrimidin- 2-ylamides of 1-r-4-hydroxy-2-oxo-1,2-dihydro- quinoline-3-carboxylic acids. synthesis,structure, and properties

The synthesis of a series of 1-R-4-hydroxy-2-oxo-1,2-dihydroquinoline-3-carboxylic acids pyrimidin-2-ylamides has been carried out with the aim of subsequent microbiological investigation. In acetic acid it was found that these compounds are brominated by 1 equivalent of bromine at position 5 of the pyrimidine ring. The only exception is the 1-allyl derivative which undergoes heterocyclization under these conditions to give 2-bromomethyl-5-oxo-1,2-dihydro-5H-oxazolo[3,2-a]quinoline-4-carboxylic acid pyrimidin-2-ylamide. The results of a study of the antitubercular activity of the synthesized compounds are presented.     

4-hydroxy-2-quinolones. 176*. 4-R-2-oxo-1,2-dihydroquinoline-3-carboxylic acids. synthesis,physicochemical and biological properties

We have carried out the synthesis and a comparative analysis of the acidic properties of a large group of 4-R-2-oxo-1,2-dihydroquinoline-3-carboxylic acids. Features of the recorded NMR spectra of these compounds are discussed together with their analgesic properties.     

Synthesis and structure of 3-(3-acetoxyalkylcarbamoyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-1-yl)propanoic acids

Treatment of 1-(2-cyanoethyl)-4-hydroxy-N-(hydroxyalkyl)-2-oxo-1,2-dihydroquinoline-3-carboxamides with a solution of hydrogen chloride in aqueous acetic acid ensures selective transformation of the cyano group into amide or carboxy with simultaneous acetylation of the hydroxyalkyl fragments.     

4-Hydroxy-2-quinolones 113. Synthesis and antitubercular activity of N-R-amides of 4-hydroxy-6-methyl-2-oxo-1-propyl-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic acid

A preparative method has been developed and the synthesis has been effected of anilides and heterylamides of 4-hydroxy-6-methyl-2-oxo-1-propyl-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic acid. A comparative analysis has been carried out of the structure and antitubercular properties of the synthesized compounds and their analogs unsubstituted in the quinoline nucleus. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 405–414, March, 2007.     

4-hydroxy-2-quinolones. 95. Synthesis, structure, and antitubercular properties of hetarylamides of 4-hydroxy-2-oxo-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic acid

The optimal conditions for obtaining hetarylamides of 4-hydroxy-2-oxo-1,2,5,6,7,8-hexahydroquinoline-3-carboxylic acid are suggested on the basis of derivatographic investigations. The ¹H NMR spectra of the synthesized compounds, their spatial structure, and also the results of a study of their antitubercular properties are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 874–886, June, 2006.