Search results for "Adipic acid"

Strukturuntersuchung von polyestern durch direkten abbau im massenspektrometer, 2. Aliphatische polyester

1976

Die Abbaureaktionen von Polyestern aus Adipinsaure und Athylenglykol 1a, Tetradeuteroathylenglykol 1b, 1,3-Propandiol 1c und 2,2′-Oxydiathanol 1d sowie aus Bernsteinsaure und Athylenglykol 2a, 1,4-Butandiol 2b und 2,2-Dimethyl-1,3-propandiol 2c wurden im Massenspektrometer untersucht. Die Polymeren wurden direkt in der Ionenquelle des Massenspektrometers pyrolysiert und die entstehenden thermischen Bruchstukke durch Elektronenstos ionisiert und fragmentiert. Die Pyrolyse- und Fragmentierungsreaktionen lassen sich nebeneinander nachweisen. Die Kenntnis der Mechanismen beider Abbauschritte ermoglicht es, strukturisomere Polyester zu unterscheiden. The degradation reactions of polyesters of ad…

N-Heterocyclic Carbene Catalyzed [3+2] Cycloaddition of Enals with Masked Cinnamates for the Asymmetric One-Pot Synthesis of Adipic Acid Derivatives.

2017

A novel short entry to 3,4-disubstituted adipic acids has been developed by employing an asymmetric NHC-catalyzed [3+2] cycloaddition of enals with masked cinnammates in moderate to good yields and high stereoselectivities. The synthetic utility of the protocol was demonstrated by the basic conversion of the masked cyclopentanone intermediates to 3S,4S-disubstituted adipic acid precursors of pharmaceutically important gababutins.

Cyclic esters of aliphatic diacids with pyrocatechol and hydroquinone

1985

Cyclic esters of adipic acid, suberic acid and sebacic acid were prepared by reaction of the acid dichlorides and pyrocatechol or hydroquinone in benzene under high dilution conditions. While only the cyclic dimers could be obtained from hydroquinone, pyrocatechol formed cyclic monomers as well as cyclic dimers (and also a cyclic dimer with succinic acid). The structure of all compounds was confirmed by1H-NMR- and mass spectra. The crystal structures of the pyrocatechol esters were determined by single crystal X-ray analysis.

ChemInform Abstract: Cyclic Esters of Aliphatic Diacids with Pyrocatechol and Hydroquinone.

1986

Cyclic esters of adipic acid, suberic acid and sebacic acid were prepared by reaction of the acid dichlorides and pyrocatechol or hydroquinone in benzene under high dilution conditions. While only the cyclic dimers could be obtained from hydroquinone, pyrocatechol formed cyclic monomers as well as cyclic dimers (and also a cyclic dimer with succinic acid). The structure of all compounds was confirmed by1H-NMR- and mass spectra. The crystal structures of the pyrocatechol esters were determined by single crystal X-ray analysis.

Diversity in Itraconazole Cocrystals with Aliphatic Dicarboxylic Acids of Varying Chain Length

2013

The cocrystal formation potential of itraconazole, a potent antifungal drug, with C2–C10 aliphatic dicarboxylic acids has been investigated. Using two experimental screening techniques (solvent-assisted grinding and evaporation-based crystallization), the cocrystals of itraconazole with C2–C7 dicarboxylic acids have been successfully synthesized and characterized by powder X-ray diffraction, solid state nuclear magnetic resonance, Raman spectroscopy, and thermal analysis. The characterized multicomponent compounds include anhydrous cocrystals (malonic, succinic, glutaric, and pimelic acids), a cocrystal hydrate (adipic acid), and cocrystal solvates with acetone and tetrahydrofuran (oxalic a…

Supercritical fluid crystallization of adipic acid using urea as habit modifier

2008

The crystal morphology of adipic acid mediated by the action of urea as additive has been investigated using the supercritical antisolvent precipitation (SAS). The process was performed using acetone and carbon dioxide as solvent and antisolvent, respectively. The effect of urea concentration in the liquid solution and of precipitation pressure on the crystal habit was investigated; the products were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), and infrared spectrometry (FT-IR). Urea was found to be very effective in modifying the crystal habit of adipic acid from needle-like shape with a length of several hun…

Relationship between adipic acid concentration and the core symptoms of autism spectrum disorders.

2016

Dicarboxylic acids are an important source of information about metabolism and potential physiopathological alterations in children with autism spectrum disorders (ASDs). We measured the concentration between dicarboxylic adipic and suberic acids in children with an ASD and typically-developing (TD) children and analyzed any relationships between the severity of the core symptoms of ASDs and other clinical features (drugs, supplements, drugs, or diet). The core symptoms of autism were evaluated using the DSM-IV criteria, and adipic acid and suberic acid were measured in urine samples. Overall, no increase in the concentration of adipic acid in children with ASDs compared to TD children, how…

Three novel synthetic amides of adipic acid protect Capsicum anuum plants against the necrotrophic pathogen Alternaria solani

2003

Three novel amides of adipic acid, 5-carbamoil ethyl pentanoate (N1), 5-(2-furfurylmethylcarbamoil) ethyl pentanoate (N2) and 5-(3-aminopropylcarbamoil) ethyl pentanoate (N3) were synthesized and their resistance-inducing activity was studied on pepper (Capsicum annuum) plants. Treatment with low doses of each amide protected pepper plants against the pathogen Alternaria solani, N1 being the most effective. Although their mode of action is still unknown, prechallenge studies demonstrated the induction of the phenylpropanoid pathway and an antisenescence effect. These effects were previously shown for other mixtures and derivatives of adipic acid. These new chemicals showed no antimicrobial …

Lysine pathway metabolites and the risk of type 2 diabetes and cardiovascular disease in the PREDIMED study: results from two case-cohort studies

2019

[Background]: The pandemic of cardiovascular disease (CVD) and type 2 diabetes (T2D) requires the identification of new predictor biomarkers. Biomarkers potentially modifiable with lifestyle changes deserve a special interest. Our aims were to analyze: (a) The associations of lysine, 2-aminoadipic acid (2-AAA) or pipecolic acid with the risk of T2D or CVD in the PREDIMED trial; (b) the effect of the dietary intervention on 1-year changes in these metabolites, and (c) whether the Mediterranean diet (MedDiet) interventions can modify the effects of these metabolites on CVD or T2D risk. [Methods]: Two unstratified case-cohort studies nested within the PREDIMED trial were used. For CVD analyses…

1967

Optically active polyamides with regular structural sequences have been prepared from L-lysine and adipic acid. A novel optically active symmetrical diamine, N.N'-bis(L-5-amino-5-carboxyl-amyl)adipamide, was obtained by treating L-lysine with adipyl chloride in the presence of copper(II) ions. The interfacial polycondensation of this diamine with adipyl chloride afforded a regular polymer, while the polycondensation of L-lysine with adipyl chloride gave an irregular polymer of the same analytical composition. The melting points, optical rotations and the optical rotatory dispersions of these polymers were investigated. Optisch aktive Polyamide mit regelmasiger Struktur wurden aus L-Lysin un…