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.     

2-(2-Hydroxy-4-methoxybenzoyl)benzoic acid derivatives of Group 4 metal alkoxides

Continued exploration of the coordination behavior of derivatives of 2-benzophenone-based ligands with metal alkoxides ([M(OR)₄]) was undertaken from the reaction of 2-(2-hydroxy-4-methoxybenzoyl)benzoic acid (H₂-OBzA) with a series of Group 4 precursors. The products of these reactions were identified as: [(OR)₂Ti(μ-(c,c-OBzA))]₂ (OR?=?OCHMe₂ (OPrⁱ; 1 ?2tol); OCMe₃ (OBu^t; 2 ?THF); OCH₂CMe₃ (ONep; 3)), [[(OPrⁱ)₃Ti(μ-OPrⁱ)Ti(OPrⁱ)₂]₂(μ-(μ_c,μ-OBzA))₂]₂ (4), [(ONep)₃Zr(μ-ONep)₂Zr(ONep)₂]₂(μ-(c,μ-OBzA)₂) (5 ?tol), [(py)(OBu^t)₃Zr]₂(μ-(c,c-OBzA)) (6), [(OBu^t)₂Hf(μ-OBu^t)]₂(μ-(c,η¹-OBzA)) (7) where ‘c’?=?chelating or η²; ‘μ’?=?bridging or η¹,η¹(O,O’); and μ_c?=?bridging chelating or η¹,η¹(O,O’); η^2?:?η¹. The metal centers for each of these compounds adopt a pseudo-octahedral geometry employing the OBzA ligand in numerous binding modes. The different functional oxygens (carboxylate, hydroxyl, and carbonyl) were employed in a variety of coordination modes for 1–7. The complexity of these OBzA-modified compounds is driven by a combination of the coordination behavior of the OBzA moieties, the size of the metal cation, and the pendant chain of the OR ligand. Solution NMR indicates a complex structure exists in solution that was considered to be consistent with the solid-state structure.     

4-羟基-2-吡啶酮的合成

以氰乙酸乙酯和原乙酸三甲酯为原料,经缩合反应制得2-氰基-3-甲氧基丁烯-2-羧酸乙酯(1);1与二甲基甲酰胺缩二甲醇缩合得2-氰基-5-(二甲氨基)-3-甲氧基-2,4-戊二烯酸乙酯(2);2在80%醋酸中环合得4-甲氧基-2-吡啶酮-3-甲酸乙酯(3);3在HBr中脱甲基和脱羧合成了4-羟基-2-吡啶酮,总收率31%,其结构经1H NMR,IR和MS确证。     

4-Hydroxy-2-quinolones. 17. Dieckmann condensation as a thermally activated process

The thermolysis of ethyl 2-ethoxycarbonylmalonanilate in boiling diphenyl oxide gave the 2-ethoxycarbonylanilide of 1H-2-oxo-4-hydroxyquinoline-3-carboxylic acid, which is also formed from the N,N-di-2-ethoxycarbonylaniline of malonic acid in the conditions of the Dieckmann reaction. The mechanism of the chemical conversions indicated is presented and discussed.For Communication 16, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1219–1222, September, 1993.     

Synthesis of 6-bromo-2-arylindoles using 2-iodobenzoic acid as precursor

The synthesis of 6-bromo-2-arylindoles starting from readily available 2-iodobenzoic acid is presented. Regioselective bromination of the latter was followed by Curtius rearrangement and trapping of the isocyanate with benzyl alcohol led to the benzyl carbamate of 2-iodo-5-bromoaniline. Chemoselective Sonogashira coupling of this compound with arylacetylenes followed by TBAF induced 5-endo-dig cyclization gave the desired bromo indoles. The method allows selective introduction of a bromine atom at the indole C-6 position.     

Succinic acid as a precursor of the tropane alkaloids

Summary The succinic acid used for the biosynthesis of the tropane alkaloids is probably included in their molecule as a whole, and forms the fragment of the alkaloid molecule consisting of carbon atoms 1, 7, 6, and 5.Khimiya Prirodnykh Soedinenii, Vol. 3, No. 6, pp. 395–397, 1967     

An approach towards the oxidation of 2-amino-4H-chromenes to 2-imino-2H-chromenes

A novel method for the synthesis of 2-imino-2H-benzo[h]chromenes via the sequential addition of N-chlorosuccinimide and triethylamine to 2-amino-4H-benzo[h]chromenes has been established. This reaction protocol represents an efficient synthetic strategy to form iminochromene derivatives under mild reaction conditions, which utilizes readily accessible aminochromenes as starting materials and tolerates a wide range of substrates.     

4-Hydroxy-2-quinolones. 56. 4-(Adamant-1-yl)thiazolyl-2-amides of 1-R-4-Hydroxy-2-oxoquinoline-3-carboxylic Acids as Potential Antitubercular Agents

The synthesis, antitubercular, anti-HIV, and antitumor activity of the 4-(adamant-1-yl)thiazolyl-2-amides of 1-R-4-hydroxy-2-oxoquinoline-3-carboxylic acids have been studied. An efficient method for purifying the 4-hydroxy-2-oxoquinoline derivatives from their metal salts is proposed.     

4-Hydroxy-2-quinolones. 16. Condensation of N-R-substituted amides of 2-carboxymalonanilic acid with o-phenylenediamine

The reaction of N-R-substituted amides of 2-carboxymalonanilic acid with the equimolar amount of o-phenylenediamine was studied under conditions of thermolysis. It was established that the main products of this reaction are the corresponding amides of benzimidazolyl-2-acetic acid and 1H-2-oxo-3-(benzimidazolyl-2)-4-hydroxyquinoline. Mechanisms of the indicated chemical conversions are discussed. The data on the study of the anticonvulsive activity of the compounds synthesized are presented.For Communication 15, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1105–1108, August, 1993.     

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-羟基-5，8-二甲氧基-萘-2-甲醛的合成

以2,5-二甲氧基苯甲醛为起始原料合成出了软毛柿木中分离到的天然产物4-羟基-5,8-二甲氧基-萘-2-甲醛,原料经过Stobbe缩合,环化,还原,氧化四步生成产物,并对醇选择性氧化成醛的过程进行了详细的研究．整个合成总的产率为32．2％．     

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. 4. selection of the optimum path for synthesis of n-r-substituted 4-hydroxy-2-quinolone-3-carboxylic acid amides

A comparison of several methods of preparation of N-R-substituted 4-hydroxy-2-quinolone-3-carboxylic acid amides showed that intramolecular cyclization of 2-carbalkoxymalonanilic acid ethyl esters with simultaneous amidation is the most rational method.See [1] for Communication 3.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 640–642, May, 1992.     

Nitric acid preparation of cellulose from miscanthus as a nitrocellulose precursor

A nitric acid method for the preparation of cellulose from miscanthus is considered. The method consists in successive treatment of the raw material with nitric acid and sodium hydroxide and affords cellulose with properties suitable for the synthesis of cellulose nitrates. The data on the nitrogen weight fraction, the viscosity, and the solubility of cellulose nitrates from miscanthus in the alcohol-ether medium are given. The miscanthus cellulose was nitrated using an industrial sulfuric-nitric acid mixture to yield cellulose nitrate samples with characteristics close to those of colloxylin.

     

4-Hydroxy-2-quinolones. 93. Synthesis and biological properties of 2-hydroxy-4-imino-1,4-dihydroquinoline-3-carboxylic acid N-R-amides

Various methods of synthesizing amides of 2-hydroxy-4-imino-1,4-dihydroquinoline-3-carboxylic acids have been studied. Results of investigations on the antitubercular and antiinflammatory activity of the obtained compounds are discussed. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 542–555, April, 2006.     

An efficient synthesis of 4-substituted coumarin derivatives via a palladium-catalyzed Suzuki cross-coupling reaction

An efficient Pd-catalyzed Suzuki cross-coupling reaction of sterically crowded 4-chlorocoumarin derivatives with air- and moisture-stable potassium organotrifluoroborates is developed. This methodology has been used to generate a series of novel alkyl, aryl, and vinyl substituted coumarin derivatives in good to excellent yields. The twisted conformation of the vinyl groups in the X-ray crystal structures of (2-oxo-4-vinyl-2H-chromen-3-yl)methyl acetate (2) and (2-oxo-4-vinyl-2H-chromen-3-yl)methyl 2,2,2-trichloroacetimidate (3), along with the atropisomerism of 3-(hydroxymethyl)-4-(2-methoxyphenyl)-2H-chromen-2-one (1d), are evidence of the steric crowding in these adducts.     

4-Chloro-3-(trifluoroacetyl)- and 4-chloro-3-(methoxalyl)coumarins as novel and efficient building blocks for the regioselective synthesis of 3,4-fused coumarins

4-Chloro-3-(trifluoroacetyl)- and 4-chloro-3-(methoxalyl)coumarins react with electron-rich aminoheterocycles, dimethyl 1,3-acetonedicarboxylate, hydrazines, alkyl thioglycolates, and methyl sarcosinate to give a variety of 3,4-heteroannulated coumarins. The starting materials were prepared by the reaction of 4-hydroxycoumarin with trifluoroacetic anhydride and methyl 2-chloro-2-oxoacetate in the presence of trimethylsilylchloride. An NMR study and X-ray crystallographic analysis are reported.