Chemistry of iminofurans: XI. Synthesis,structure, and cyclization of 4-substituted 2-(aroylhydrazinylidene)-4-oxobutanoic acids

Aromatic hydrazides reacted with 4-aryl-2-hydroxy-4-oxobut-2-enoic and 2-hydroxy-5,5-dimethyl- 4-oxohex-2-enoic acids to give 4-aryl-2-(2-aroylhydrazinylidene)-4-oxobutanoic and 5,5-dimethyl-2-(aroylhydrazinylidene)- 4-oxohexanoic acids. The products were found to exist in solution as mixtures of Z/E-hydrazinylidene and cyclic dihydropyrazole tautomers, and they underwent intramolecular cyclization to 5-aryland 5-tert-butyl-3-(aroylhydrazinylidene)furan-2(3H)-ones by the action of acetic anhydride.     

Chemistry of iminofurans: VI.* Synthesis and structure of 2-(2-ylidenehydrazino)-substituted 4-aryl-4-oxobut-2-enoic and 5,5-dimethyl-4-oxohex-2-enoic acids

Hydrazones derived from substituted benzophenones and fluorenone reacted with 4-aryl-2-hydroxy-4-oxobut-2-enoic and 2-hydroxy-5,5-dimethyl-4-oxohex-2-enoic acids to give the corresponding 2-(2-ylidenehydrazino) derivatives which may be used as initial compounds for the synthesis of 3-hydrazono-3H-furan-2-ones. The obtained but-2-enoic and hex-2-enoic acid derivatives in solution may exist as Z- and E-isomeric enehydrazine tautomers or hydrazone tautomers with syn or anti orientation of substituents with respect to the double C=N bond.     

Synthesis and Structure of Disodium 1,2-Bis(2-oxocycloalkylidene)ethane-1,2-diolates and Disodium 4-Alkoxy-4-oxo-1-(2-oxocycloalkylidene)but-2-ene-1,2-diolates

Russian Journal of General Chemistry - Two-stage condensation of cycloalkyl ketones with dimethyl oxalate or alkyl acetates with dialkyl oxalates and cycloalkyl ketones produced disodium...     

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.     

Chemistry of iminofurans: IX. Synthesis and cyclization of (2<Emphasis Type="Italic">Z</Emphasis>)-2-{(2<Emphasis Type="Italic">Z</Emphasis>)-2-[2-(3-R-adamantan-1-yl)-2-oxoethylidene]hydrazinyl}-4-(het)aryl-4-oxobut-2-enoic acids

1-(3-R-adamantan-1-yl)-2-[(triphenyl-λ⁵-phosphanylidene)hydrazinylidene]ethanone reacted with 4-aryl(hetaryl)-2,4-dioxobutanoic acids to give 2-{2-[2-(3-R-adamantan-1-yl)-2-oxoethylidene]hydrazinyl}-4-aryl(hetaryl)-4-oxobut-2-enoic acids which were shown to exist in solution as mixtures of Z- and E-isomeric enehydrazine tautomers. The products underwent cyclization to 3-{[2-(3-R-adamantan-1-yl)-2-oxoethylidene]- hydrazinylidene}-5-aryl(hetaryl)furan-2(3H)-ones.     

Synthesis,Intramolecular Cyclization,and Antinociceptive Activity of Substituted 2-[2-(4-Nitrobenzoyl)hydrazinylidene]-4-oxobut-2-enoic Acids

Russian Journal of Organic Chemistry - New substituted 2-[2-(4-nitrobenzoyl)hydrazinylidene]-4-oxobut-2-enoic acids have been synthe­sized by condensation of 4-nitrobenzohydrazide with...     

4-hydroxy-2-quinolones. 18. Synthesis and antithyroid activity of 1-R-2-oxo-3-(4-oxo-3H-quinazolin-2-yl)-4-hydroxyquinolines

Preparative methods for the synthesis of 1-R-2-oxo-3-(4-oxo-3H-quinazolin-2-yl)-4-hydroxyquinolines based on ethyl esters or nitrites of 1-R-2-oxo-4-hydroxyqidnoline-3-carboxylic acids and anthranilamide or ethyl anthranilate correspondingly were proposed. The antithyroid activity of the compounds synthesized was studied.For Communication 17, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1223–1226, September, 1993.     

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.     

Synthesis of 1-R-2-amino-3-[2-(benz)azolyl]-4(5H)-ketopyrroles

A study has been made of the interaction of 2-[2-(benz)azolyl]3-keto-4-chlorobutanenitriles with primary aliphatic amines. This is a convenient method for the synthesis of 2-amino-3-[2-(benz)azolyl]-4(5H)-ketopyrroles.Tarasa Shevchenko Kiev University, Kiev 252601, Ukraine; e-mail dov@fosfor.kiev.ua. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 50–57, January, 1998.     

Synthesis of 2(r)-[3(s)-acylamino-2-oxo-1 azetidinyloxy]-acetic acids

The title compounds when constructed from a-aminoxyacetic esters coupled with N-benzyloxycarbonyl-L-serine in the presence of N-ethoxycarbonyl-2-ethoxy L-2-(benzyloxyformamido)-3-hydroxypropionamidooxy acetates. Alternative coupling with N-benzyloxycarbonyl-L-serine 3,4-dihydro-4-oxo-l,2,3-benzotriazin triphenyl phosphine and dimethyl azodicarboxylate gave the fully protected monocyclic β-lactams. In the phenylacetic acid series hydrogenolytic deprotection led to decomposition. However, in the phenylpropionic series the hydrogenolysis product was sufficiently stable to allow acylation by the thiol ester route to the title compound.     

Synthesis,Structure, and Biological Activity of 4-R-4-Oxo-2-[2-(phenylamino)benzoyl]hydrazinylidene- N -hetarylbutanamides

Decyclization of N′-[5-R-2-oxofuran-3(2H)-ylidene]-2-(phenylamino)benzohydrazides under the action of heterocyclic amines leads to the formation of N-hetaryl-4-R-4-oxo-2-[2-(phenylamino)benzoyl]hydrazinylidenebutanamides. Antinociceptive and anti-inflammatory activity of the obtained compounds was studied.     

Synthesis of 4-R-2,2-dimethyl-1,2-dihydrobenzo[f]isoquinolines and (2,2-dimethyl-1,2-dihydrobenzo[f]isoquinolylidene-4)acetic acid derivatives

4-R-2,2-dimethyl-1,2-dihydrobenzo[f]isoquinolines and (2,2-dimethyl-1,2-dihydrobenzo[f]isoquinolylidene-4)acetic acid derivatives have been prepared by Ritter reactions of substituted acetonitriles with 2-methyl-1-(1-naphthyl)propan-2-ol.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 375–376, March, 1992.     

Polarographic behavior of 4-aryl-2-(1,2-diphenyl-2-oxoethylidenehydrazino)-4-oxo-2-butenoic acids

Polarographic reduction of 4-aryl-2-(1,2-diphenyl-2-oxoethylidenehydrazino)-4-oxo-2-butenoic acids in 2-propanol-water solutions proceeds with the formation of two or three irreversible cathode waves and leads to 4-aryl-2-(1,2-diphenyl-2-hydroxyethylhydrazino)-4-hydroxybutanoic acids. The latter suffer hydrolysis with the rupture of the C²-NH bond and the formation of 4-aryl-2,4-dihydroxybutanoic acids.     

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.     

Chemistry of iminofurans. Recyclization of ethyl 2-[2-oxo-5-phenylfuran-3(2H)-ylideneamino]-4,5,6,7-tetrahydro-1-benzothiophene-3-carboxylate in reaction with amines

Russian Journal of Organic Chemistry - The reaction of ethyl 2-[2-oxo-5-phenylfuran-3(2H)-ylideneamino]-4,5,6,7-tetrahydro-1-benzothiophene- 3-carboxylate with primary amines (RNH2) in toluene...     

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.