Synthesis of aliphatic amino dicarboxylic acids from thiophene

Summary By hydrogenolysis of the corresponding thiophene derivatives, the following aliphatic amino dicarboxylic acids were prepared: 2-aminodecanedioic, 2-aminoundecanedioic, and 5-aminotridecanedioic acids.     

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.     

Amino esters of heterocyclic dicarboxylic acids

The corresponding amino esters and their hydrochlorides and quaternary salts were obtained by the condensation of 2,5-furan- and 2,5-tetrahydrothiophenedicarboxylic acid chlorides with 1-methyl-, 1-ethyl-, or 1-butyl-3-hydroxypiperidines.deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 515–518, April, 1971.     

Preparation of bislupinine esters of dicarboxylic acids

Conclusions A number of bislupinine derivatives and their methiodides were synthesized.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 946–947, April, 1972.     

The ionization of aliphatic dicarboxylic acids in water

Potentiometric, calorimetric, and dilatometric data on the ionization of several saturated dicarboxylic acids in water at 25°C are reported. A correlation is attempted between structure and thermodynamic evidences for the two dissociation stages of the diacids considered, in particular in terms of the propensity toward intramolecular hydrogen bond formation of some singly ionized species.     

Conformational study of methyl esters of some aliphatic erythro- and threo-dichlorocarboxylic acids

The average conformations of methyl esters of some aliphatic erythro- and threo-dichlorocarboxylic acids in dilute carbon tetrachloride solutions have been determined from the vicinal proton–proton coupling constants and ¹H NMR shifts. The ¹³C shift differences between the erythro and threo forms are compared and discussed with regard to the differences in the average conformations.     

Plasticization of cellulose diacetate with a mixture of triacetin and esters of butylcellosolve and aliphatic dicarboxylic acids

The compatibility of cellulose diacetate with triacetin and esters of butylcellosolve with dicarboxylic aliphatic acids was studied for a wide range of compositions. The glass transition temperature T _g ,the dielectric relaxation activation energy and the tensile creep for the plasticized systems were determined. It is shown that when the esters are added to triacetin in small amounts, which correspond to the formation of compatible systems, the plasticizing effect is enhanced and the molecular mobility of the system components is improved.     

Synthesis of cellulose esters with aliphatic hydroxy acids from aspen wood

Synthesis of cellulose esters with aliphatic hydroxy acids from aspen wood was studied in relation to the reaction and isolation conditions.     

Synthesis and degradabilities of polyesters from 1,4:3,6-dianhydrohexitols and aliphatic dicarboxylic acids

Six different polyesters ( 6a–6c and 7a–7c ) were prepared by the bulk polycondensations of the respective combinations of 1,4:3,6-dianhydro-D-glucitol ( 3 ) and 1,4:3,6-dianhydro-D-mannitol ( 4 ) with succinyl dichloride ( 5a ), glutaryl dichloride ( 5b ), and adipoyl dichloride ( 5c ) at 140–180°C. Polyesters having number average molecular weights up to 2.6 ×10⁴ were obtained in high yields. Only polyester 7a based on 4 and 5a was partially crystalline, whereas all the other polyesters were amorphous. Thin films of these polyesters except that of 7a were spontancously hydrolyzed in a neutral phosphate buffer solution at 50°C, whereas they were reluctant to be hydrolyzed at 27°C. The polyesters were more or less degraded at 27°C by treatment with an activated sludge or by prolonged burial in soil. © 1995 John Wiley & Sons, Inc.     

Complexation of aliphatic dicarboxylic acids and anions by alpha-cyclodextrin

Inclusion complexes are formed in aqueous solution between -cyclodextrin and several straight-chain alkanedioic acids (ethanedioic, propanedioic, butanedioic, pentanedioic, hexanedioic, heptanedioic and octanedioic acids), several corresponding anions, several straight-chain alkenedioic acids (cis-butanedioic,trans-butanedioic andt,t-2,4-hexadienedioic acids) and several corresponding anions. Formation constants for these complexes were determined by measuring the effect of complexation on the pH of cyclohexaamylose/acid/base buffer equilibria. Enthalpies and entropies of complexation were calculated from the temperature dependences of the formation constants. The observed trends in the thermodynamic parameters lead to hypotheses about the structures of the complexes.     

Synthesis of some thioglycidyl esters of monobasic carboxylic acids

Thioglycidyl esters of monobasic carboxylic acids were synthesized by thioepoxidation of glycidyl esters of thiourea.Translated from Khimiya Geterotsiklicheskikh Soedinenii No. 5, pp. 588–590, May, 1989.     

Mass spectra of piperidine dicarboxylic acids and their esters

Electron impact mass spectra of the epimers of 2,4-, 2,5-, and 2,6-piperidine dicarboxylic acids and their methyl esters and N-acyl derivatives have been studied. Data from DADI spectra have been used to establish the basic fragmentation paths. Chemical ionization spectra of positive and negative ions of 2,4- and 2,5-piperidine dicarboxylic acids are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1490–1495, November, 1986.     

Investigation and radiometric determination of saturated and unsaturated aliphatic dicarboxylic acids

Radiometric determination of saturated and unsaturated aliphatic dicarboxylic acids has been developed using a precipitation reaction. The influence of the conditions of precipitation, the composition of the calcium salts of the acids, thepH, and the composition of solvent mixtures were investigated. The solubility of the calcium salts diminished with an increase of the ethanol content in weakly alkaline medium. Linear relations were found between the solubilities of the calcium salts and the dielectric constants of the solvent mixtures. The calcium salts have poor solubilities atpH 9 in 20% aqueous ethanol containing ammonia. The radiometric titrations were carried out in 0.05M solutions, using 0.05M ⁴⁵Ca-labelled CaCl₂ solution in 20% aqueous ethanol. The titrations were done in an apparatus suitable for the detection of soft β-emitting isotopes.