Littérature scientifique sur le sujet « Imine acids »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres

Choisissez une source :

Consultez les listes thématiques d’articles de revues, de livres, de thèses, de rapports de conférences et d’autres sources académiques sur le sujet « Imine acids ».

À côté de chaque source dans la liste de références il y a un bouton « Ajouter à la bibliographie ». Cliquez sur ce bouton, et nous générerons automatiquement la référence bibliographique pour la source choisie selon votre style de citation préféré : APA, MLA, Harvard, Vancouver, Chicago, etc.

Vous pouvez aussi télécharger le texte intégral de la publication scolaire au format pdf et consulter son résumé en ligne lorsque ces informations sont inclues dans les métadonnées.

Articles de revues sur le sujet "Imine acids"

1

Zarei, Maaroof. « One-step Synthesis of β-lactams Using Cyanuric Fluoride ». Journal of Chemical Research 37, no 1 (janvier 2013) : 25–27. http://dx.doi.org/10.3184/174751912x13545429290478.

Texte intégral
Résumé :
Cyanuric fluoride works as an efficient acid activator reagent for the direct [2+2] ketene–imine cycloaddition of substituted acetic acids and imines in a one-pot synthesis under mild conditions. The yields are good to excellent and the reaction conditions are mild, simple and efficient.
Styles APA, Harvard, Vancouver, ISO, etc.
2

Wulff, William, Xin Zhang et Yijing Dai. « The Acceleration of the Rearrangement of α-Hydroxy Aldimines by Lewis or Brønsted Acids ». Synlett 29, no 15 (28 août 2018) : 2015–18. http://dx.doi.org/10.1055/s-0037-1610262.

Texte intégral
Résumé :
An efficient method was developed for the synthesis of α-amino ketones from α-hydroxy imines. The reaction occurs through an α-iminol rearrangement involving the migration of a substituent of the carbinol carbon to the imine carbon. The optimal catalysts were found to be silica gel or montmorillonite K 10, which effected migration of a variety of aryl and alkyl substituents in high yields. The rearrangement can also be carried out on imines generated in situ from aldehydes and amines in essentially the same yields as those from the preformed imines.
Styles APA, Harvard, Vancouver, ISO, etc.
3

Sikervar, Vikas, Ravindra Sonawane, Raghuramaiah Mandadapu, Amol Satish Dehade, Shrikant Abhiman Shete et Mark Montgomery. « Lewis Acid Mediated [3+2] and [3+3] Annulations of an Azomethine Imine with Donor–Acceptor Cyclopropanes ». Synthesis 53, no 16 (10 mai 2021) : 2865–73. http://dx.doi.org/10.1055/a-1503-8068.

Texte intégral
Résumé :
AbstractTwo different Lewis acids were used for developing [3+2] and [3+3] regioselective cycloaddition reactions of an azomethine imine with activated cyclopropanes. Scandium(III) triflate catalyzes a [3+2] cycloaddition reaction of the azomethine imine with cyclopropanes to form tetrahydropyrazolone derivatives and tricyclic tetrahydrofuran derivatives in moderate yields. Complementary to this, a novel [3+3] cycloaddition reaction of the azomethine imine with activated cyclopropanes was developed by using EtAlCl2 as a Lewis acid to form hexahydropyridazinone derivatives in high regioselectivity.
Styles APA, Harvard, Vancouver, ISO, etc.
4

Morales Salazar, Daniel, Arvind Kumar Gupta et Andreas Orthaber. « Reactivity studies of an imine-functionalised phosphaalkene ; unusual electrostatic and supramolecular stabilisation of a σ2λ3-phosphorus motif via hydrogen bonding ». Dalton Transactions 47, no 31 (2018) : 10404–9. http://dx.doi.org/10.1039/c8dt01607k.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Alex, S., P. Turcotte, R. Fournier et D. Vocelle. « Study of the protonation of simple Schiff bases in solvents of various polarity by means of Raman spectroscopy ». Canadian Journal of Chemistry 69, no 2 (1 février 1991) : 239–45. http://dx.doi.org/10.1139/v91-038.

Texte intégral
Résumé :
In this study, the protonation of simple Schiff bases by organic acids in various solvents is investigated by Raman spectroscopy and the spectral response of the C=N+ stretching mode is correlated with the macroscopic properties of the medium surrounding the imine. Upon protonation, the unperturbed C=N stretch increases in frequency due to the combination of the coupling with the C=N+H bend and a partial rehybridization of the C=N bond. Depending on the proton location relative to that of its counterion, one mechanism may prevail over the other. Intensity measurements show that protonation is mostly controlled by the hydrogen bonding properties of the solvent and by the polarity of the medium. However, whatever the solvent, full proton transfer cannot be achieved with organic acids with pKa similar to the COOH of amino acids found in visual or bacterial pigments, meaning that the protonation mechanism may depend upon particular properties of the protein. Key words: imines, protonation, Raman spectroscopy, rhodopsin, Schiff base.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Wang, Hao-Ran, En-He Huang, Chen Luo, Wen-Feng Luo, Yin Xu, Peng-Cheng Qian, Jin-Mei Zhou et Long-Wu Ye. « Copper-catalyzed tandem cis-carbometallation/cyclization of imine-ynamides with arylboronic acids ». Chemical Communications 56, no 35 (2020) : 4832–35. http://dx.doi.org/10.1039/d0cc01424a.

Texte intégral
Résumé :
An efficient copper-catalyzed regioselective cis-carbometallation/cyclization of imine-ynamides with arylboronic acids enables the facile and practical synthesis of valuable 2,3-disubstituted indolines.
Styles APA, Harvard, Vancouver, ISO, etc.
7

Bissonnette, Martine, Hoa Le Thanh et Daniel Vocelle. « Interaction of strong acids with a conjugated imine ». Canadian Journal of Chemistry 63, no 8 (1 août 1985) : 2298–302. http://dx.doi.org/10.1139/v85-379.

Texte intégral
Résumé :
The state of protonation of a Schiff base, trans-trans-heptadienylidene tert-butylamine (HBA) was evaluated by uv and 1H nmr spectroscopies. Using three strong acids, HCl, HBr, HI and by taking spectra at low temperatures, it was found that in a non-polar solvent like chloroform (or CDCl3), no proton exchange occurred between the iminium ion and the halide anion. In contrast, CD3OH induced a leveling effect and some proton transfer occurred between the iminium ion and the solvent for the HBr and HI salts. No proton exchange was present for the HBA:HCl salt. The interaction of trichloroacetic acid with HBA was also studied: full proton exchange occurred between the iminium ion and CD3OH. In CDCl3, proton transfer was also present between the iminium ion and the carboxylate anion. These facts are discussed in relation with the controversy surrounding the true state of protonation of rhodopsin.
Styles APA, Harvard, Vancouver, ISO, etc.
8

Bakulina, Olga, Alexander Ivanov, Vitalii Suslonov, Dmitry Dar’in et Mikhail Krasavin. « A speedy route to sterically encumbered, benzene-fused derivatives of privileged, naturally occurring hexahydropyrrolo[1,2-b]isoquinoline ». Beilstein Journal of Organic Chemistry 13 (18 juillet 2017) : 1413–24. http://dx.doi.org/10.3762/bjoc.13.138.

Texte intégral
Résumé :
A series of 15 benzene-fused hexahydropyrrolo[1,2-b]isoquinolonic acids with substantial degree of steric encumbrance has been prepared via a novel variant of the Castagnoli–Cushman reaction of homophthalic anhydride (HPA) and various indolenines. The employment of a special kind of a cyclic imine component reaction allowed, for the first time, isolating a Mannich-type adduct between HPA and an imine component which has been postulated but never obtained in similar reactions.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Zaccheria, Federica, Federica Santoro, Elvina Iftitah et Nicoletta Ravasio. « Brønsted and Lewis Solid Acid Catalysts in the Valorization of Citronellal ». Catalysts 8, no 10 (22 septembre 2018) : 410. http://dx.doi.org/10.3390/catal8100410.

Texte intégral
Résumé :
Terpenes are valuable starting materials for the synthesis of molecules that are of interest to the flavor, fragrance, and pharmaceutical industries. However, most processes involve the use of mineral acids or homogeneous Lewis acid catalysts. Here, we report results obtained in the liquid-phase reaction of citronellal with anilines under heterogeneous catalysis conditions to give tricyclic compounds with interesting pharmacological activity. The terpenic aldehyde could be converted into octahydroacridines with a 92% yield through an intramolecular imino Diels–Alder reaction of the imine initially formed in the presence of an acidic clay such as Montmorillonite KSF. Selectivity to the desired product strongly depended on the acid sites distribution, with Brønsted acids favoring selectivity to octahydroacridine and formation of the cis isomer. Pure Lewis acids such as silica–alumina with a very low amount of alumina gave excellent results with electron-rich anilines like toluidine and p-anisidine. This protocol can be applied starting directly from essential oils such as kaffir lime oil, which has a high citronellal content.
Styles APA, Harvard, Vancouver, ISO, etc.
10

Ahmad, Rasool, Rizwan, Altaf, Rashid, Mahmood et Ayub. « Role of Pyridine Nitrogen in Palladium-Catalyzed Imine Hydrolysis : A Case Study of (E)-1-(3-bromothiophen-2-yl)-N-(4-methylpyridin-2-yl)methanimine ». Molecules 24, no 14 (17 juillet 2019) : 2609. http://dx.doi.org/10.3390/molecules24142609.

Texte intégral
Résumé :
In the present study, 4-methylpyridin-2-amine was reacted with 3-bromothiophene-2-carbaldehyde and the Schiff base (E)-1-(3-bromothiophen-2-yl)-N-(4-methylpyridin-2-yl)methanimine was obtained in a 79% yield. Coupling of the Schiff base with aryl/het-aryl boronic acids under Suzuki coupling reaction conditions, using Pd(PPh3)4 as catalyst, yielded products with the hydrolysis of the imine linkages (5a–5k, 6a–6h) in good to moderate yields. To gain mechanistic insight into the transition metal-catalyzed hydrolysis of the compounds, density functional theory (DFT) calculations were performed. The theoretical calculations strongly supported the experiment and provided an insight into the transition metal-catalyzed hydrolysis of imines.
Styles APA, Harvard, Vancouver, ISO, etc.

Thèses sur le sujet "Imine acids"

1

Saha, Manik Chandra. « Physico-chemical studies on coordination compounds of imine acids with dioxouranium (VI) and trivalent lanthanide ions ». Thesis, University of North Bengal, 1988. http://hdl.handle.net/123456789/764.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Evans, Caroline. « A novel methodology for the asymmetric synthesis of beta-lactams and beta-amino acids ». Thesis, University of Bath, 2012. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.558881.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Baskakova, Alevtina. « Synthesis of branched [alpha]-[alpha-] and [beta]-amino[beta-amino] acids using C-nucleophile additions to imines and nitrones ». Berlin Logos-Verl, 2009. http://d-nb.info/99789301X/04.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Garbay, Guillaume. « Nouvelles voies de synthèse sans métaux d'oligomères et de polymères π-conjugués pour l'électronique organique ». Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0240/document.

Texte intégral
Résumé :
Dans cette thèse sont développées les synthèses et caractérisations de nouveaux polymères conjugués pour des applications dans l’électronique organique. Ces polymères ont été synthétisés via des réactions de polymérisation sans utilisation de métaux de transition. Des polyazomethines à base de carbazole ont ainsi été synthétisés par polycondensation entre des carbazole portant des fonctions amine et aldéhyde en positions 2,7 et 3,6. Leurs propriétés optiques et électroniques ont été étudiées en fonction de la position des fonctions imines ainsi formées. Un comonomère de type EDOT a ensuite été intégré dans le polymère et l’impact de ce comonomère sur les propriétés du copolymère ainsi formé a été étudié.Des polymères à base d’acide squarique et croconique ont ensuite été synthétisés. En faisant varierles conditions de synthèse, les propriétés optoélectroniques ont pu être contrôlées, permettant d’obtenir des composés présentant une émission blanche, qui ont ensuite été intégrés en tant que couche active dans des dispositifs de type OLED.Enfin, des polymères plus originaux ont été étudiés, utilisant des réactions de polymérisation originale, permettant par exemple la formation de benzobisthiazole in situ. D’autres polymères ont été synthétisés en intégrant dans leur chaine des monomères originaux, comme la tetrazine ou la divanilline. Les propriétés optoélectroniques de ces composés ont ensuite été étudiées en vue deleur éventuelle intégration dans des dispositifs
In this work, synthesis and characterizations of new conjugated polymers are described.These polymers, developed for their integration into devices, have been synthesized via transitionmetalfree polymerizations. Carbazole based polyazomethines have been synthesized via polycondensation reactions between di-substituted carbazoles, bearing amino and formyl functionsin positions 3,6 or 2,7. Optical and electronical properties of such polymers have been studieddepending of the linkage position. A comonomer EDOT has then been integrated into the polymer chain, and impact of such insertion has been studied. Squaric and croconic acid base polymers have also been synthesized. By varying polymerization conditions, optoelectronic properties have been tuned, leading to the formation of polymers exhibiting a white emission. These polymers have then been integrated into OLED, as the active layer. Finally, more original polymers have been synthesized, using more original reactions or monomers such as by forming in situ benzobisthiazole. Other polymers integrating more originals monomers, such a tetrazine or divanillin, have been synthesized. Optoelectronic properties of such materials have been studied for the purpose of their integration into devices
Styles APA, Harvard, Vancouver, ISO, etc.
5

Ward, Simon Edward. « Novel amino-acids from imino Diels-Alder reactions ». Thesis, University of Cambridge, 1997. https://www.repository.cam.ac.uk/handle/1810/283723.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

Capra, Julien. « Synthese biomimetique de composes azotes biologiquement actifs ». Thesis, Paris 11, 2011. http://www.theses.fr/2011PA112030.

Texte intégral
Résumé :
Ce travail de thèse est consacré à la synthèse de composés azotés biologiquement actifs s’inspirant notamment d’une réaction biosynthétique. Dans un premier temps, nos travaux avaient pour but de développer une nouvelle voie d’accès aux acides alpha-aminés par une réaction d’isomérisation énantiosélective d’imines. Après différentes études préliminaires, les meilleurs précurseurs d’acides alphaaminés par cette méthode que nous ayons identifiés sont les alpha céto amides. L’isomérisation 1,3 d’une imine formée à partir d’un alpha céto amide et de la diphénylméthanamine à l’aide de différents alcoolates chiraux a été réalisée. L’utilisation de l’alcoolate dérivé de la (+)-N-méthylpseudoéphédrine, employé en quantité sub-stœchiométrique, a permis d’obtenir l’alpha amino amide correspondant avec un excès énantiomérique de 67%. Il reste encore à mettre au point des conditions opératoires satisfaisantes pour la conversion de cet adduit en acide alpha aminé. L’étude de l’isomérisation 1,3 d’imines nous a permis de mettre en évidence une réaction de déshydrogénation 1,4 permettant d’accéder de façon originale à des 2-azadiènes et nécessitant la présence d’oxygène. Ainsi, plusieurs 2-azadiènes non activés ont été préparés par traitement basique d’imines issues de la condensation d’acétophénones et de diphénylméthanamine sous atmosphère d’air. Dans une dernière partie, l’étude de l’addition conjuguée d’une oxazolidinone chirale sur des alkylidènemalonates de dialkyle a été réalisée dans le but de développer une méthode d’accès à des acides alpha aminés. Les conditions opératoires mises au point ont permis d’obtenir une excellente diastéréosélectivité à partir de la plupart des alkylidènemalonates de dialkyle
This thesis work is devoted to the synthesis of biologically active nitrogen-containing compounds, particularly inspired by a biosynthetic reaction. Initially, our work aimed to develop a new pathway to a-amino acids using anenantioselective imine isomerization reaction. After various preliminary studies, the best precursors of a-amino acids that we have identified are a-keto amides. The 1,3isomerization of an imine formed from an a-keto amide and diphenylmethanamine using various chiral alkoxides was then conducted. The alkoxide derived from (+)-N-méthylpseudoéphédrine, employed in sub-stoichiometric quantities, allowed obtaining the corresponding a-amino amide with 67% enantiomeric excess. It still remains to develop satisfactory operating conditions for the conversion of this adduct to an a-amino acid.The study of the 1,3 isomerization of imines allowed us to bring to light a 1,4 dehydrogenation reaction, which allows an original access to 2-azadienes and which requires the presence of oxygen. Thus, several non-activated 2-azadienes have been prepared by basic treatment of imines derived from acetophenones anddiphenylmethanamine, under air atmosphere.In the last part, the study of the conjugate addition of a chiral oxazolidinone on dialkyl alkylidenemalonates was carried out, with the aim to develop a method of access to enantiopure b-amino acids. Reactions conditions developed allowed to obtain an excellent diastereoselectivity from most dialkyl alkylidenemalonates
Styles APA, Harvard, Vancouver, ISO, etc.
7

Jones, Catrin A. « The asymmetric synthesis of #alpha#-amino acids from imines ». Thesis, Bangor University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263167.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
8

Lewis, Kirk Alexander. « Stereoselective synthesis using aminyl radicals derived from α-amino acids ». Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/32976.

Texte intégral
Résumé :
Chapter 1 is the introduction to the thesis. It contains an overview of amino acids and aminyl radicals. The amino acids section includes material on their synthesis through traditional methods and asymmetric syntheses, as well as the use of radical reactions in their formation. The aminyl radical section gives a description of the nature of the radical and then proceeds with general techniques for aminyl radical formation. A more detailed account of our own group's use of sulfenamides and imines in aminyl radical formation is ·covered and the chapter is ended with a look at the work of aminyl radicals in amino acid synthesis and my subsequent intentions in this area. The preparation and cyclisation of sulfenamide precursors derived from [alpha]-amino acids is discussed in chapter 2. Both the cyclisations of aminyl and urethanyl (introduction of benzyloxycarbonyl and tosyl protecting groups onto amine) radicals onto suitably placed alkenyl substituents were investigated. 5-Exo-trig cyclisation reactions successfully afforded the cyclic products in moderate yield with reasonable diastereoselectivity. The effects of the [alpha]-CO2R (where R = Me or tBu), the size of the amino acid side chain and placement of alkenyl substituent (N-substituted or sidechain containing alkene) are discussed. The use of imines as aminyl radical precursors is explored in chapter 3. [Alpha]-amino acids and aldehydes were condensed and the cyclisation products isolated. The formation of aminyl radicals by 5-exo-trig cyclisation and subsequent H-atom abstraction gave moderate to good yields of N-cyclopentyl substituted a-amino acids. Preparation of the aldehydes is discussed. Tandem cyclisations involving aspects of chapters 2 and 3 are looked at in chapter 4. The preparation of the unnatural a-amino acids required for tandem cyclisation and subsequent formation of the sulfenamide or imine is reported. 5-Exo, 6-exo cyclisation of the sulfenamide derivative gave the tandem product in low yield and with moderate diastereoselectivity. This was in contrast to the imine derived reaction which proved unsuccessful. The remaining chapters incorporate the detailing of experimental relevant to the discussion and the presentation of references quoted throughout the thesis.
Styles APA, Harvard, Vancouver, ISO, etc.
9

Betit, Lyanne. « Derivatization of Azomethine Imines into beta-Aminocarbonyl Motifs ». Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32473.

Texte intégral
Résumé :
β-Aminocarbonyl motifs are a privileged substructures in medicinal chemistry and peptidomimetics. As part of our efforts toward metal free aminations, we developed a method for intermolecular amino-carbonylation of alkenes using hydrazones. This method provides access to cyclic azomethine imines containing a β-aminocarbonyl motif. Conceptually, these dipoles can be derivatized into many bioactive compounds, such as 1,3-diamines, β-amino amides and β-amino acids. The first part of this thesis will present the results on the derivatization of our aminocarbonylation products into various nitrogen-containing molecules, such as β-amino amides, β-amino acids and pyrazolones. More specifically, a short, chromatography-free derivatization of azomethine imines into N-Boc-β-amino amides will be presented. Following these results, the next chapter will focus on attempts at develop novel aminocarbonylation reactivity between 1,2-diacylhydrazines and alkenes followed by results from our reductive N-N bond cleavage experiments on our cyclic hydrazides.
Styles APA, Harvard, Vancouver, ISO, etc.
10

Hartley, James Holroyd. « Saccharide accelerated hydrolysis of boronic acid imines ». Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369335.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.

Livres sur le sujet "Imine acids"

1

Hartley, James Holroyd. Saccharide accelerated hydrolysis of boronic acid imines. Birmingham : University of Birmingham, 2000.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Santanilla, Alexander Buitrago. New Approaches Towards the Asymmetric Allylation of the Formyl and Imino Groups via Strained Silane Lewis Acids. [New York, N.Y.?] : [publisher not identified], 2013.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Rosenthal, Gerald. Plant Nonprotein Amino and Imino Acids : Biological, Biochemical, and Toxicological Properties. Elsevier Science & Technology Books, 2012.

Trouver le texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.

Chapitres de livres sur le sujet "Imine acids"

1

Elford, Tim G., et Dennis G. Hall. « Catalytic Additions of Allylic Boronates to Carbonyl and Imine Derivatives ». Dans Boronic Acids, 393–425. Weinheim, Germany : Wiley-VCH Verlag GmbH & Co. KGaA, 2011. http://dx.doi.org/10.1002/9783527639328.ch8.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Batey, Robert A. « Nucleophilic Addition Reactions of Aryl and Alkenylboronic Acids and Their Derivatives to Imines and Iminium Ions ». Dans Boronic Acids, 279–304. Weinheim, FRG : Wiley-VCH Verlag GmbH & Co. KGaA, 2006. http://dx.doi.org/10.1002/3527606548.ch7.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

Cavallini, Doriano, Giorgio Ricci, Silvestro Duprè, Laura Pecci, Mara Costa, Rosa M. Matarese, Bernardo Pensa, Antonio Antonucci, Sandro P. Solinas et Mario Fontana. « Sulfur-containing cyclic ketimines and imino acids ». Dans EJB Reviews 1991, 257–63. Berlin, Heidelberg : Springer Berlin Heidelberg, 1991. http://dx.doi.org/10.1007/978-3-642-77200-9_19.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Tracey, M. R., R. P. Hsung, J. Antoline, K. C. M. Kurtz, L. Shen, B. W. Slafer et Y. Zhang. « Imine/Enamide Rearrangement ». Dans Three Carbon-Heteroatom Bonds : Esters and Lactones ; Peroxy Acids and R(CO)OX Compounds ; R(CO)X, X=S, Se, Te, 1. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-021-00408.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
5

Coates, C., J. Kabir et E. Turos. « Ketene–Imine Cycloadditions ». Dans Three Carbon-Heteroatom Bonds : Esters and Lactones ; Peroxy Acids and R(CO)OX Compounds ; R(CO)X, X=S, Se, Te, 1. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-021-00569.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
6

« Reduction ». Dans Biocatalysis in Organic Synthesis : The Retrosynthesis Approach, 73–112. The Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/bk9781782625308-00073.

Texte intégral
Résumé :
This chapter covers enzyme classes that catalyse reduction reactions, including ketoreductases, enoate reductases, carboxylic acid reductases, imine reductases, amino acid dehydrogenases, opine dehydrogenases, amine dehydrogenases and nitro reductases. The chapter is divided into separate sections, each detailing the reduction of a specific functional group, including ketones, aldehydes, carboxylic acids, alkenes, imines, nitro aromatics, sulfoxides, azides, n-oxides and azo compounds. Each section begins with a review of chemical methods of carrying out each transformation, followed by a description of the enzyme classes that are also capable of carrying it out. The substrate scope of each enzyme class, including its chemo-, regio- and stereoselectivity, is discussed and a general mechanism for the enzyme-catalysed reaction is presented. Where appropriate, strategies for co-factor recycling are also included. This should give the reader a rounded understanding of when and how to carry out reduction reactions using enzymes.
Styles APA, Harvard, Vancouver, ISO, etc.
7

« Coenzyme Forms of Vitamin B6 ». Dans The Chemical Biology of Human Vitamins, 193–227. The Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/bk9781788014649-00193.

Texte intégral
Résumé :
Vitamin B6 in supplements is provided as pyridoxine and converted in vivo to the side chain-phosphorylated pyridine aldehyde, pyridoxal-phosphate (PLP). The conjugated heterocyclic aldehyde can engage in imine formation with amino acids in specific enzyme sites preparatory to stabilized amino acid Cα-carbanion formation in the amino acid-PLP aldimines. From such accessible carbanionic intermediates, chemistry at Cα, Cβ, and Cγ, including retroaldol chemistry and C–C bond formations, occurs in more than 100 human enzyme sites. Indeed, the PLP coenzyme is synonymous with human amino acid metabolism
Styles APA, Harvard, Vancouver, ISO, etc.
8

Coates, C., J. Kabir et E. Turos. « Ester Enolate–Imine Cyclocondensations ». Dans Three Carbon-Heteroatom Bonds : Esters and Lactones ; Peroxy Acids and R(CO)OX Compounds ; R(CO)X, X=S, Se, Te, 1. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-021-00574.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
9

Perst, H. « Connective Imine Formation by the Reaction of Thioketenes with Sulfur ­Diimides ». Dans Three Carbon-Heteroatom Bonds : Thio-, Seleno-, and Tellurocarboxylic Acids and Derivatives ; Imidic Acids and Derivatives ; Ortho Acid Derivatives, 1. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-023-00772.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
10

Perst, H. « Connective Imine Formation by Aza-Wittig Reaction of Iminophosphoranes or Related Compounds with Ketenes ». Dans Three Carbon-Heteroatom Bonds : Thio-, Seleno-, and Tellurocarboxylic Acids and Derivatives ; Imidic Acids and Derivatives ; Ortho Acid Derivatives, 1. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-023-00767.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.

Actes de conférences sur le sujet "Imine acids"

1

Mallakpour, Shadpour. « Microstructure and properties of novel optically active poly(ester-imide)/TiO2 bionanocomposites containing natural amino acids moieties ». Dans 2010 International Conference on Enabling Science and Nanotechnology (ESciNano). IEEE, 2010. http://dx.doi.org/10.1109/escinano.2010.5701084.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
2

Pather, Kaveshree, Nuala A. Helsby, Brian D. Palmer et Lai-Ming Ching. « Abstract 1555:In vitroandin vivoevaluation of analogs ofN-(o-carboxybenzoyl)glutamic acid imide, an active thalidomide metabolite ». Dans Proceedings : AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010 ; Washington, DC. American Association for Cancer Research, 2010. http://dx.doi.org/10.1158/1538-7445.am10-1555.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
3

WU, ZHIJIAN, FUQIANG BAN et RUSSELL J. BOYD. « THEORETICAL STUDY ON THE REACTION MECHANISMS OF THE IMIDE FORMATION IN AN N-(O-CARBOXYBENZOYL)-L-AMINO ACID ». Dans Proceedings of the International Symposium on Solid State Chemistry in China. WORLD SCIENTIFIC, 2002. http://dx.doi.org/10.1142/9789812776846_0077.

Texte intégral
Styles APA, Harvard, Vancouver, ISO, etc.
4

Bigović, Miljan, Marija Kaluđerović, Jovana Jovanović, Haris Majstorović et Milica Kosović-Perutović. « Synthesis of Schiff bases between some five-membered heterocyclic aldehydes and thiocarbohydrazide (TCH) and optimization of reaction conditions ». Dans 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.435b.

Texte intégral
Résumé :
The usual way of synthesizing imines (Schiff bases) between carbonyl compounds –aldehydes and ketones – with thiocarbohydrazide (TCH) involves heating them for 3 hours in a mixture of water solvents and ethanol with the addition of a catalytic amount of concentrated hydrochloric acid. Heating in the presence of acid catalysts over a long period of time may be unsuitable for acid-sensitive, labile, reactive or thermally unstable aldehydes, which are prone to polymerization under these conditions. We tested the condensation reaction at room temperature with a series of aldehydes, while maintaining the described ratios (equimolar ratio of aldehydes and TCH), with the addition of a few drops of 36% HCl. The course and completion of the reaction were monitored using infrared spectroscopy (FTIR). The reaction time is longer compared to the heating conditions, while the yields are comparable. We obtained a series of compounds of high degree of purity, satisfactory yield varying from 50-90%, whose structure and purity were confirmed by NMR spectroscopy.
Styles APA, Harvard, Vancouver, ISO, etc.
5

Haynes, A., et P. Gouma. « Nanoengineering Polyaniline for Advanced Chemosensing Applications ». Dans ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-10310.

Texte intégral
Résumé :
The focus of this study is the development of polyaniline based hybrid systems for selective room temperature detection of NO2. The electrospinning technique has been employed to produce highly dispersed nanocomposites of leucoemeraldine base polyaniline (LEB-PANI) with cellulose acetate (CA) as a secondary component. The nanocomposites exhibit sensitivity and selectivity to NO2 down to 1 ppm with response time of 70s and recovery time of 155s. Spectroscopic analyses of the nanocomposites reveal that the molecular interactions between cellulose acetate and LEB-PANI yields enhanced sensitivity and selectivity to NO2. DC electrical resistance measurements of the composite during exposure to the analyte suggest that the response mechanism has some dependency on the humidity level in the gas chamber. This is found to be partly attributed to the byproduct of hydrolyzed CA: acetic acid. Infrared spectroscopy reveals that the acetate ions from the acid and polymer transforms base groups of LEB-PANI to higher oxidized states and affix to quinoid, benzenoid, and imine groups along polyaniline’s chain. These sites operate as additional reactions sites along the polymer backbone for increased ion mobility and aid in retaining the sensor’s stability and selectivity under varying gas atmospheres. This paper details the results from sensing experimentation and classical characterization techniques in an effort to develop a paradigm for chemical sensing with CA-PANI nanocomposites.
Styles APA, Harvard, Vancouver, ISO, etc.
6

Lee, Chi-Hung, Jia-Ru Chen, Hung-Wei Shiu, Ko-Shan Ho, Shinn-Dar Wu, Kuo-Huang Hsieh et Yen-Zen Wang. « Effect of Bridging Groups on Sulfonated Poly(Imide-Siloxane) for Application in Proton Exchange Membrane of Fuel Cells ». Dans ASME 2008 6th International Conference on Fuel Cell Science, Engineering and Technology. ASMEDC, 2008. http://dx.doi.org/10.1115/fuelcell2008-65155.

Texte intégral
Résumé :
A series of six-membered sulfonated poly(imide-siloxane)s were synthesized using 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA), aminopropyl-terminated polydimethylsiloxane (PDMS) 2,2-benzidinedisulfonic acid (BDSA), as the sulfonation target diamine groups, and various non-sulfonated diamine monomers behaving as bridging groups. The structure-property relationship of SPI-SXx membranes is discussed in details according to the chemical structure of the nvarious non-sulfonated diamines of SPI-SXx membranes from the viewpoints of proton conductivity, ion exchange capacity (IEC) and membranes properties (water uptake, membrane swelling) at equal PDMS content SPI-SXx. They showed good solubility and high thermal stability up to 300 °C. The PDMS was introduced to enhance the proton conductivity and water uptake attributed from the highly flexibility of the siloxane segments. They showed a comparable or even higher proton conductivity than that of Nafion 117 in water at 60 °C. The conductivity and water uptake of angled, SPI-SXm and ODA-based SPI-SX membranes (SPI-SXO) are greater than those prepared from DDM-based SPI-SX membranes (SPI-SXD) at a given IEC. These differences resulted from the increased numbers of entanglements of the flexibility membrane. The SPI-SXD showed alomost isotropically dimensional changes with the increases of water uptake and the volume were slightly smaller than those estimated from the additivity rule. Microscopic analyses revealed that these smaller (<10 nm) and well-dispersed hydrophilic domains contribute to the better proton conducting properties. The new sulfonated poly(imide-siloxane)s have proved to be a possible candidate as the polymer electrolyte membrane for PEFCs and DMFCs.
Styles APA, Harvard, Vancouver, ISO, etc.
Nous offrons des réductions sur tous les plans premium pour les auteurs dont les œuvres sont incluses dans des sélections littéraires thématiques. Contactez-nous pour obtenir un code promo unique!

Vers la bibliographie