Reaction of organozinc reagents formed in reaction of dibromomalonic acid dialkyl esters and zinc, with 2-arylmethylenemalonic acid dinitriles and 3-aryl-2-cyanopropenoic acid methyl esters

Organozinc compounds, obtained from dibromomalonic acid dialkyl esters and zinc, react with 2-arylmethylmalonic acid dinitriles and 3-aryl-2-cyanopropenoic acid methyl esters forming 3-aryl-2,2-dicyanocyclopropane-1,1-dicarboxylic acid dialkyl esters and 3-aryl-2-cyanocyclopropane-1,1,2-tricarboxylic acid trimethyl esters. ¹H and ¹³C NMR, ³ J _CH constants are considered.     

1-Substituted aziridine-2,2-dicarboxylic acid esters

The synthesis and chemical properties of aziridine-2,2-dicarboxylic acid esters were investigated. The activation parameters of the inversion of the nitrogen atom in 1-substituted aziridine-2,2-dicarboxylic acid esters were determined. The inv values of a number of substituents attached to the nitrogen atom were established.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 346–351, March, 1985.     

Synthesis and oxidation of 2,6-dimethyl-1,4-dihydropyridine-3, 5-dicarboxylic acid esters

Twenty-six esters of 2,6-dihydropyridine-3,5-dicarboxylic acid were obtained by means of the Hantzsch pyridine synthesis. The synthesized compounds were oxidized by chloranil to the corresponding pyridine derivative.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1230–1237, September, 1975.     

The spatial structure of the isomeric dimethyl esters of 4-hydroxypiperidine-2, 6-dicarboxylic acid

Three isomeric dimethyl esters of 4-hydroxypiperidine-2, 6-dicarboxylic acid have been isolated. The spatial structures of all three isomeric esters and of the acids corresponding to them have been established on the basis of NMR spectra. It has been shown that while the isomers I and II exist in the form of only one conformation each, isomer III in neutral and acid media apparently consists of an equilibrium mixture of two (or more) conformers. The information obtained on the spatial structure of the isomeric esters shows that the cyclization of these compounds with benzylamine and p-nitrobenzaldehyde takes place with the inversion of the piperidine ring.     

Derivatives of diazirine-3,3-dicarboxylic acid

The amidation and alkaline hydrolysis of diazirine-3,3-dicarboxylic acid esters, which proceed with retention of the diazirine ring, were studied. The higher stability of diazirine-3,3-dicarboxylic acid esters as compared with their spirocyclic analogs is explained by the conformational lability of the C=O groups. The UV and mass spectra of the diazirines are discussed.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 901–906, July, 1981.     

Quaternary ammonium salts of bis-3-azatricyclo[5,3,0,11,5]undecane

The reaction of the anhydride of exo-cis-bicyclo[3,3,0]octane-2,4-dicarboxylic acid with ammonia followed by the reduction of the resulting imide with lithium aluminum hydride has yielded 3-azatricyclo[5,3,0,1^1,5]undecane, from which a number of quaternary bisammonium salts have been obtained with dihaloalkanes. These salts have also been synthesized from the anhydride of exo-cis-bicyclo[3,3,0] octane-2,4-dicarboxylic acid and polymethylenediamines.     

Amino esters of heterocyclic dicarboxylic acids

The corresponding amino esters and their complexes with 7,7,8,8-tetracyanoquinodimethane were obtained by the condensation of the acid dichlorides of furan-2,5-dicarboxylic acid and tetrahydrothiophene-2,5-dicarboxylic acid with 8-hydroxy- and 5,7-dibromo-8-hydroxyquinolines. Almost all of the compounds obtained have antimicrobial activity.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 538–540, April, 1972.     

Stereoselective electrocatalytic cyclization of 3-substituted 2,2-dicyanocyclopropane-1,1-dicarboxylic acid esters to form 6-substituted (1R,5R,6R)*-4,4-dialkoxy-5-cyano-2-oxo-3-azabicyclo[3.1.0]hexane-1-carboxylic acid esters

Electrolysis of 3-substituted 2,2-dicyanocyclopropane-1,1-dicarboxylic acid esters in alcohols in an undivided cell in the presence of NaBr or NaOAc afforded 6-substituted (1R,5R, 6R)*-4,4-dialkoxy-5-cyano-2-oxo-3-azabicyclo[3.1.0]hexane-1-carboxylic acid esters in 80–95% yields. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 102–107, January, 2006.     

Synthesis and reduction of derivatives of aziridinemono- and-dicarboxylic acids

Amides and esters of aziridine-2-carboxylic acid were synthesized by the reaction of 1,1,1-trimethyl-2-(2-carboxyethyl)hydrazinium derivatives with an anion-exchange resin or with sodium hydride. Enamines were obtained from 1,1,1-trimethyl-2-[1,2-bis(alkoxycarbonyl)ethyl]hydrazinium salts and basic agents. Methods for the synthesis of amides of aziridine-2,2- and aziridine-2,3-dicarboxylic acids were developed. The stereochemistry of the esters and amides of aziridine-2,3-dicarboxylic acids was established. Dialkylcarbamoylaziridines were reduced with lithium aluminum hydride to 2-(N,N-dialkylaminomethyl)aziridines. The reduction of esters of aziridine-2-carboxylic acid and their functionally substituted derivatives leads to the formation of 2-hydroxymethylaziridines. An O-silylation product was obtained by silylation of 2-hydroxymethylaziridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1227–1235, September, 1983.     

Triphenodioxazine-1,8-dicarboxylic acid as an oxidation product of 3-hydroxyanthranilic acid

The oxidation of 3-hydroxyanthranilic acid (30HA) 1 by aqueous buffered potassium ferricyanide produces a number of coloured compounds. These include cinnabarinic acid 2 (yellow), a p-quinone dimer 3 (red) and 9-carboxy-2-hydroxy-3H-phenoxazin-3-one 4 (brown). Also present by tlc is a bright pink compound. The structure of this compound has been demonstrated to be triphenodioxazine-1,8-dicarboxylic acid 5a .     

Electrochemical reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in an aprotic medium

The polarographic reduction of 1, 4-dihydropyridine-3, 5-dicarboxylic acid derivatives in dimethylformamide was studied. It is shown that the first diffusion waves of these compounds are irreversible one-electron waves and correspond to electrical reduction of the C=C bond of the conjugated system of the 1, 4-dihydropyridine ring to give a tetrahydro derivative. In the case of pyridine-3, 5-dicarboxylic acid esters partial dimerization of the resulting freeradical products occurs along with electron transfer. It is shown that the introduction of alkoxycarbonyl substituents in 2, 6-methyl and 3, 5-methoxycarbonyl groups and in the 4 position and of a carboxyl group in the 4 position facilitates the electrical reduction of the 1, 4-dihydropyridine ring. The introduction of a methyl group in the 4 position hinders reduction of the ring.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 641–646, May, 1978.     

Preparation of 1H,2H- and 1H-cyclopropene-3,3-dicarboxylic acid esters and 1H,2H-cyclopropene-3,3-dicarboxylic acid from the corresponding trimethylsilyl derivatives

Conclusion The feasibility was shown for use of the silyl protection method for the synthesis of 1H- or 2H-cyclopropene-3,3-dicarboxylic acids and their esters. The preparation of 1H,2H-cyclopropene-3,3-dicarboxylic acid and its dimethyl ester by this method was demonstrated for the first time.For the previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2803–2805, December, 1986.     

Synthesis and oxidation of 2,6-dimethyl-3, 5-di(phenoxycarbonyl)-1,4-dihydropyridines

A number of new aryl esters of acetoacetic acid were obtained in the reaction of phenols with diketene in the presence of triethylamine. Reaction of the esters thus obtained with hexamethylenetetramine gave, for the first time, aryl esters of 1,4-dihydropyridine-3,5-dicarboxylic acid, the oxidation of which with chloranil gave the corresponding pyridines.     

1-Acyloxyaziridine-2,2-dicarboxylic acid esters

The reaction of diazomethane and O-acylisonitrosomalonates gave ²-1,2,3-triazoline-5,5-dicarboxylic acid esters, the rates of formation and thermal stabilities of which are determined by the character of ths substituent attached to the oxygen atom. Thermolysis of the triazolines leads to mixtures of 1-acyloxyaziridine-2,2-dicarboxylic acid esters and isomeric dialkyl O-acylisonitrososuccinates; acidolysis with BF₃·Et₂O makes it possible to obtain exclusively aziridines. The acidic decompositions of dimethyl 4-methyl-²-1,2,3-triazoline-5,5-dicarboxylate, which was obtained from the reaction of diazoethane and dimethyl O-tosylisonitrosomalonate, leads to dimethyl -tosyloxyamino--vinylmalonate. A dependence of the spin-spin coupling constants (SSCC) of the protons of the aziridine ring on the electronegativities of the substituents attached to the oxygen atom was observed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 338–342, March, 1984.     

2-Alkylisoxazolidine-3,3-dicarboxylic acid derivatives

1,3-Dipolar cycloaddition of,-bis(alkoxycarbonyl)-N-alkylnitrones to olefins gave 2-alkylisoxazolidine-3,3-dicarboxylic acid esters, the yields of which are determined by the steric conditions and are virtually independent of the electronic effect of the substituents attached to the C=C bond of the dipolarophiles. The structures of the compounds obtained were established by analysis of the PMR spectra. The retention of the cis configuration of the substituents in the isoxazolidines obtained from maleic acid esters constitutes evidence for a one-step, four-center, concerted cycloaddition mechanism. The energy parameters for inversion of the nitrogen atom of dimethyl 2,5,5-trimethylisoxazolidine-5,5-dicarboxylate were measured.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 599–603, May, 1979.     

Pyrolysis of 3-hydroxy-2-arylhydrazonoalkanoic acid derivatives

1,2-Diaza-1,3-butadienes have been obtained from readily available 3-hydroxy-2-arylhydrazonopropanoates under various reaction conditions including pyrolysis, dehydration under Mitsunobu conditions or with acetic anhydride or acetic acid. According to their method of synthesis these 1,2-diaza-1,3-butadienes underwent subsequent reactions to give interesting products, and in the presence of proper dienophiles gave the corresponding cycloaddition products. Also, a new approach to pyrazole-3-carboxylic acid derivatives was discovered during an attempt to dehydrate 3-hydroxy-2-arylhydrazonobutanoic esters.     

A new oxidation process. Transformation of gem-bishydroperoxides into esters

A new oxidation process has been found where α,ω-dicarboxylic acid esters and ω-hydroxycarboxylic acid esters are formed on heating gem-bishydroperoxides in alcohol in the presence of BF₃·Et₂O. By addition of H₂O₂ to this reaction α,ω-dicarboxylic acid esters are formed almost selectively.     

Synthesis of unsaturated esters of pyridine- and quinolinedicarboxylic acids

The divinyl, diallyl, and dipropargyl esters of pyridine-2,4-, pyridine-2,6-, and quinoline-2,4-dicarboxylic acids and the divinyl and dipropargyl esters of pyridine-2,5-dicarboxylic acid have been synthesized.     

胆甾类分子钳对氨基酸衍生物的对映选择性识别

用差紫外光谱滴定法考察了以脱氧胆酸作spacer的手性分子钳1～3对一系列α-氨基酸甲酯的对映选择性识别性能。结果表明,分子钳1和2与客体氨基酸甲酯形成1:1型超分子配合物,并显示较好的手性识别能力。分钳3对所考察的氨基酸甲酯均没有明显的识别作用。讨论了主-客体间尺寸/形状匹配、几何互补等因素对形成超分子配合物的影响,并利用计算机模拟作辅助手段对实验结果和现象进行了解释。     

Derivatives of heterocyclic α-iminocarboxylic acids 3. Synthesis of N-alkoxycarbonyl and N-alkoxycarbonylalkenyl derivatives of α-iminocarboxylic acids

By the interaction of L-proline, L-thioproline, pipecolic acid, tetrahydro-1,4-thiazine-3-carboxylic acid, and diastereomeric esters of tetrahydro-1,4-thiazine-3,5-dicarboxylic acid with methyl chloroformate, methyl propiolate, and acetylenecarboxylic acid, we have obtained N-alkoxycarbonyl and N-alkoxycarbonylalkenyl derivatives of -iminocarboxylic acids. By the reaction of N-methoxycarbonyltetrahydro-1,4-thiazine-3-carboxylic acid with hydrazine hydrate, we have obtained 8-amino-7,9-dioxo-4-thia-1,8-diazabicyclo[4.3.0]nonane.For communication 2, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1561–1566, November, 1993.