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Dissertations / Theses on the topic 'Aliphatic acids'

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Published: 5 June 2025

Last updated: 24 June 2025

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1

Jing, Stanley Mofor. "Synthesis of Resveratrol Esters and Aliphatic Acids." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etd/1382.

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Resveratrol (RV) is a naturally occurring phytoalexin of the stilbenoid family produced by some plant species, and present in grape skin, peanuts, and red wine. It has been found to exhibit anti-cancer, anti-inflammatory, anti-viral, anti-aging, cardio protective, and anti-oxidant properties. Bioavailability is a huge setback that limits the potentials of RV. As a result, efforts have been made to design and synthesize RV esters and aliphatic acids in an attempt to increase its bioavailability, solubility in water, and possibly improving its biological activities. Resveratrol esters, 3,5,4'-triacetyloxystilbene (2) and Methyl 1,1',1''- (3,4',5-stilbenyl)-1,6-hexanedioate (3) have been synthesized. Compound 3 is a new compound, synthetic yield is 88%, and purity is above 95% based on NMR integration. Both 2 and 3 are good candidates for biological evaluation. 3 was used as a precursor in the synthesis of resveratrol aliphatic acid, 8-(3',5'-dihydroxylstilbene-4''-oxy)-3,6-dioxocotanoic acid (9). First, 2 was hydrolyzed to resveratrol diester, 3,5-diacetyloxystilbene (4). Mitsunobu reaction of 4 and methyl 8-hydroxy-3,6-dioxooctanoate (7) was then carried out to afford methyl 8-(3',5'-diacetyoxystilben-4''-oxy)-3.6-dioxooctanoate (/5), which was then hydrolyzed to afford 9 in total 43.6 % yield. Structures of all newly synthesized compounds were confirmed by 1H and 13C NMR spectroscopy.

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2

Durand, Pierre-Luc. "Fatty acids as a source of original aliphatic polycarbonate materials." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0710.

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Cette thèse porte sur la valorisation de dérivés d’acides gras dans l’objectif d’élaborer des matériaux polycarbonates aliphatiques (PCAs) bio-sourcés originaux. Dans cette optique, deux plateformes de carbonates cycliques à 6 chaînons (6CCs) ont été synthétisés en utilisant des voies d’accès impliquant soit la formation d’un intermédiaire de type malonate ou un couplage entre un acide gras et le 2-amino-1,3-propanediol. La polymérisation par ouverture de cycle de ces monomères a été étudiée. La première plateforme de 6CCs a été polymérisée en présence de Sn(Oct)2 comme catalyseur, donnant accès à des polycarbonates de faible Tg allant de -61°C jusqu’à-26°C du fait de longues chaines latérales pendantes. La polymérisation de la seconde plateforme de6CCs a été effectuée de manière contrôlée en utilisant un système catalytique composé de la DBU et d’une thio-urée. Tirant profit de ces polycarbonates aliphatiques bio-sourcés linéaires porteurs d’insaturations, des matériaux originaux réticulés ont été synthétisés. Plusieurs méthodes de réticulation ont été testées telles que le couplage thiol-ène irréversible, la réaction de Diels-Alder thermo-réversible et la cyclo-addition photo-réversible [2+2] entre deux groupements cinnamate.Ainsi, des PCAs réticulés issus d’acides gras ont été synthétisés et caractérisés; ces derniers possèdent des propriétés physico-chimiques modulables selon la nature des monomères de départ etla densité de réticulation des réseaux<br>Fatty acids were derivatized with the objective to design bio-based aliphatic polycarbonate(APC) materials. To that purpose, two platforms of lipidic 6-membered cyclic carbonates were prepared following synthetic routes either involving the ring-closure of a malonate intermediate or the coupling reaction between a fatty acid and 2-amino-1,3-propanediol. The ring-openingpolymerization (ROP) of these cyclic carbonates was next investigated. The first platform of 6CCswas polymerized in the presence of Sn(Oct)2 as catalyst, yielding low Tg aliphatic polycarbonates ranging from -61°C to -26°C with respect to the size of the pendant aliphatic side chains. The polymerization of the second lipidic 6CC platform was performed in a controlled fashion using DBU/Schreiner thiourea as catalytic system. Taking advantage of the presence of unsaturation functions on the linear bio-based APCs, cross-linked polycarbonate materials were then prepared.Several cross-linking methods were tested such as the irreversible thiol-ene coupling, the thermoreversible Diels-Alder reaction and the photo-reversible [2+2] cyclo-addition reaction between two cinnamate moieties. Fatty acid-based cross-linked APCs were thus designed and characterized; the latter exhibit tunable physico-chemical properties as a function of the monomer structure and the cross-linking density

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3

Wu, Wai Shing. "Measurements of amino acids and aliphatic amines in ambient aerosols /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?CHEM%202003%20WU.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.<br>Includes bibliographical references (leaves 226-231). Also available in electronic version. Access restricted to campus users.

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4

Schory, David Henry. "Quantum Chemical Investigations of Nucleophilic Aromatic Substitution Reactions and Acid Dissociations of Aliphatic Carboxylic Acids." Wright State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=wright1253480264.

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5

Gillmore, Adam Thomas. "Poly-L-leucine : applications to asymmetric catalysis and stereoselective synthesis." Thesis, University of Liverpool, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366977.

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6

Shen, Steve I. "Arg-Gly-Asp (RGD) conjugated aliphatic acids as micellar drug carrier for targeted drug delivery." Scholarly Commons, 2004. https://scholarlycommons.pacific.edu/uop_etds/2641.

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Targeted drug delivery is desired in cancer therapy since most of the side effects common to chemotherapy are related to the toxicity of the drug. Integrin over-expression has been shown in various cancer cells and can be exploited for targeted drug delivery. The goal of this study is to design amphiphilic conjugates with targeting motifs as a targeted drug delivery carrier. Toward this effort, novel amphiphilic conjugates of the Arg-Gly-Asp (RGD) peptide or GRGDS was linked to aliphatic acids of varying chain length. The hypothesis is that these novel amphiphilic conjugates, at concentrations above the critical micelle concentration (CMC), can form micelles in aqueous environment, encapsulate poorly-water soluble drugs, and target the α v β 3 integrin. The amphiphilic conjugate is also hypothesized to serve as targeting moiety in mixed micelle drug delivery system using Pluronic block copolymer. Synthesis of RGD amphiphilic conjugates was achieved by converting carboxylic acids into more reactive N-hydroxysuccinimidyl derivative and converting the carboxylic functional group of peptide into methyl ester. Then the activated NHS aliphatic ester was conjugated with methyl-protected peptide in the presence of organic base and methyl ester was removed in NaOH and subsequently neutralized. Intermediates and final products were characterized by MS, FTIR, and NMR. Micelle formation occurred in concentration of 0.015 to 0.12 mM for C 14 -RGD, C 16 -RGD, C 18 -RGD, and C 18 -GRGDS. Amphiphilic conjugate mixed with Pluronic L121 and Pluronic P104 (5% C 18 -RGD/L121 and 10% C 18 -GRGDS/P104) formed micelles at lower CMC of 0.0006 and 0.01 mM, respectively. Solubility of Taxol in water was improved by 87% when encapsulated in C 18 -RGD micelle above CMC. The solubility was increased 7 fold and 18 fold in mixed micelles of 5% C 18 -RGD/P104 and 5% C 18 -RGD/L121 above CMC. Three different drugs (DOX, Taxol, and etoposide) were used to evaluate the efficacy of the targeting C 18 -GRGDS micelle carrier alone or C 18 -RGD mixed with Pluronic block copolymers micelle. All 3 drugs significantly enhanced cytotoxicity toward cancer cells when loaded in micelle carrier above CMC. With same DOX concentration, C 18 -GRGDS micelle carrier significantly decreased percent of viable cells (12.9 ± 1.2%) above CMC when compared to concentrations below CMC (24.1 ± 1.0%). Mixed micelle of targeting amphiphile and Pluronic loaded with Taxol above CMC significantly decreased the percent of viable cells (38.3 ± 7.9%) when compared to non-targeting Pluronic block copolymer micelle (56.0 ± 2.8%). (Abstract shortened by UMI.)

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7

fadhil, ali abd al-karim alkarim. "Reversed-phase and surfactant modified reversed-phase high and ultra-high performance liquid chromatography of phenolic and aliphatic carboxylic acids." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1574428923192499.

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8

Ulrich, Hans-Jakob. "The adsorption of aliphatic fatty acids at aquatic interfaces : a comparison between polar and nonpolar surfaces /." [S.l.] : [s.n.], 1986. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=7967.

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9

Itsenko, Oleksiy. "Photoinitiated Radical Carbonylation Using [11C]Carbon Monoxide : 11C-Labelling of Aliphatic Carboxylic Acids, Esters, and Amides." Doctoral thesis, Uppsala universitet, Kemiska institutionen, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6021.

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One-step photoinitiated free radical carbonylation was employed for the rapid (5–7 min) labelling of aliphatic carboxylic acids, esters, and amides with a short-lived positron emitter 11C (t½ = 20.3 min) at the carbonyl position. The labelled compounds were synthesized from alkyl iodides (0.05–0.1 mmol), [11C]carbon monoxide, and appropriate nucleophiles. Decay-corrected radiochemical yields were up to 74%; conversion of [11C]carbon monoxide reached 85–90%; specific radioactivity was 158–192 GBq/mmol. The labelled compounds were identified and characterized using HPLC, LC-MS, and 1H and 13C NMR. The effects of solvents, additives, photoirradiation, temperature, and reaction time were studied and discussed. [carbonyl-11C]Amides were synthesized using amines in 1–2 equiv. to iodides, exploiting solvent effects to control reactivity. [carboxyl-11C]Acids were synthesized using water as a nucleophile, in binary and ternary aqueous solvent mixtures; the addition of TBAOH or KOH was necessary to obtain high radiochemical yields. [carbonyl-11C]Esters were synthesized using primary and secondary alcohols, tert-butanol, and phenol. Bases were KOH, BuLi, LiHDMS. The effects of photosensitizers were studied and exploited to accelerate the labelling of carboxylic acids and esters resulting in 75–85% decay-corrected radiochemical yields under mild conditions without the use of bases. A mild procedure for the 11C-carboxylation of alkyl iodides using DMSO as an oxygen nucleophile was developed. This method is expected to be suitable in the macroscale synthesis of carboxylic acids using isotopically unmodified carbon monoxide. Radical carbonylation was applied to improve the synthesis of an extensively used PET tracer, [carbonyl-11C]WAY-100635. The tracer was synthesized in one step, whereas a common approach via Grignard reagents requires three steps. In addition, several (13C)compounds were synthesised using the described methods. Free radical carbonylation may be used for the 11C-carbonylation of alkyl iodides, whereas transition-metal carbonylation – of aryl halides and triflates. Thus, the two carbonylation methods are complementary with respect to the scope of synthetic targets.

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10

Fasciano, Jennifer Marie. "Use of Surfactant Modifiers for High-Performance Liquid Chromatography of Aliphatic and Aromatic Acids and Capillary Electrophoresis of Glycosaminoglycans." Miami University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=miami1448126648.

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11

Leite, Goncalo M. "Potential for control of spoilage and mycotoxigenic species using mixtures of anti-oxidants, aliphatic acids and molecular approaches using RNAi." Thesis, Cranfield University, 2013. http://dspace.lib.cranfield.ac.uk/handle/1826/8632.

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In recent years, consumer perceptions are that they would like minimum levels of preservatives or even preservative free food. However, this leads to higher risks of microbial spoilage problems, especially due to growth of spoilage fungi, which are capable of growth at intermediate environmental conditions. Studies have been carried out to evaluate the effect of different preservatives at optimal and sub-optimal concentrations on growth, biosynthesis of mycotoxin production at a molecular and phenotypic level for Fusarium graminearum (Tri5) and trichothecene production and Penicillium verrusocum (otapksPv) and ochratoxin A (OTA) production. These were complimented by studies on development of RNAi approaches to inhibit key regulatory genes in the biosynthetic pathways for mycotoxins in these two species. Additional studies were carried out to develop a rapid technique for RNA extraction from fungal biomass. Initial liquid media based studies identified the growth boundaries of a range of 20 spoilage fungi including 3 mycotoxigenic species in relation to preservatives and pH. This showed that up to the legal allowable concentrations of sorbic and benzoic salts at pH 3.0 all strains were capable of growth after 24h. With the exception of F. graminearum all the other species and strains of spoilage fungi were able to grow in these conditions. The use of a mixture of preservatives, a common practise in the food industry, proved effective at inhibiting growth of most spoilage fungi for 21 days at the EU legal limits. Over the EU legal limit of 250 ppm of potassium sorbate mixed with 150 ppm of sodium benzoate only Aspergillus niger had observable growth. Mixtures of weak organic acids, fumaric and malic acid, with the preservative potassium sorbate was shown to be effective at inhibiting growth below the legal limits of use of these food additives, even though the presence of potassium sorbate appears to be fundamental to the inhibition effect, of these natural food additives. Moreover the presence of fumaric acid stimulated growth of Aspergillus flavus. The extraction of high quality total RNA from low amounts of mycelium showed that up to 3 times higher yields can be achieved while improving RNA integrity and overall quality. This development also reduced the time required to extract fungal RNA and the risk of cross-contamination showing the potential use in high throughoutput gene expression studies. In vitro and In situ studies demonstrated the risk of using single sub-optimal antifungal compounds to inhibit growth and mycotoxin production. For F. graminearum, while growth was reduced, the Tri5 gene expression and trichothecenes type B production were stimulated in the presence of thyme essential oil, Prochloraz and BHA. This was also shown with P. verrucosum where otapksPv gene expression and OTA production were stimulated at different water conditions by the presence of sub-optimum concentrations of thyme essential oil and Prochloraz. The antioxidant BHA was able to reduce both otapksPv expression and OTA production in P. verrucosum. The use of siRNA oligonucleotides to silence Tri5 and otapksPv demonstrated that both F. graminearum and P. verrucosum possess the RNAi pathway machinery. In both mycotoxigenic fungi the expression of the target key biosynthetic pathway was knocked down. The optimum levels of the designed siRNA molecules were of between 10 and 25 nM for the molecules targeting P. verrucosum otapksPv. Even though gene silencing using siRNA molecules is transient the effect on otapksPv was still observable after 15 days. This lead to a 3 to 5 times a reduction in the amount of OTA. On the other hand, the silencing of Tri5 in F. graminearum was only detectable in the first 6 days after transfection.

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12

Itsenko, Oleksiy. "Photoinitiated Radical Carbonylation Using [¹¹C]Carbon Monoxide : ¹¹C-Labelling of Aliphatic Carboxylic Acids, Esters, and Amides." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis: Univ.-bibl. [distributör], 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6021.

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13

Stoller, André. "Synthese d'analogues structuraux de l'acide arachidonique, inhibiteurs potentiels de la 5-lipoxygenase." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13165.

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14

Gellibert, Françoise. "Synthese d'analogues structuraux a motif captodatif et de nouveaux metabolites de l'acide arachidonique : actions sur la 5-lipoxygenase." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13031.

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La synthese d'inhibiteurs de la biosynthese des leucotrienes a ete developpee selon deux voies: -synthese de metabolites naturels de l'acide arachidonique (monoepoxides) -synthese de produits analogues de l'acide arachidoniques susceptibles de stabiliser l'intermediaire radicalaire forme au cours de la premiere etape de la 5-lipoxygenase

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15

Zschaler, Josefin, and Jürgen Arnhold. "The hydroperoxide moiety of aliphatic lipid hydroperoxides is not affected by hypochlorous acid." Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-189197.

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The oxidation of polyunsaturated fatty acids to the corresponding hydroperoxide by plant and animal lipoxygenases is an important step for the generation of bioactive lipid mediators. Thereby fatty acid hydroperoxide represent a common intermediate, also in human innate immune cells, like neutrophil granulocytes. In these cells a further key component is the heme protein myeloperoxidase producing HOCl as a reactive oxidant. On the basis of different investigation a reaction of the fatty acid hydroperoxide and hypochlorous acid (HOCl) could be assumed. Here, chromatographic and spectrometric analysis revealed that the hydroperoxide moiety of 15S-hydroperoxy-5Z,8Z,11Z,13E-eicosatetraenoic acid (15-HpETE) and 13S-hydroperoxy-9Z,11E-octadecadienoic acid (13-HpODE) is not affected by HOCl. No reduction of the hydroperoxide group due to a reaction with HOCl could be measured. It could be demonstrated that the double bonds of the fatty acid hydroperoxides are the major target of HOCl, present either as reagent or formed by the myeloperoxidase-hydrogen peroxide-chloride system.

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16

Micas-Languin, Dominique. "Preparation d'aldehydes alpha-hydroxyles chiraux : application a la synthese de metabolites de l'acide arachidonique et de composes biologiquement actifs." Paris 6, 1987. http://www.theses.fr/1987PA066527.

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La preparation des composes du titre se fait a partir du d-mannitol via la decyclisation par des nucleophiles de diepoxydes; les alpha -hydroxy aldehydes obtenus ont ete utilises pour preparer le leucotriene b**(4) et un de ses homologues en c21

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17

Dryzhakov, Marian. "Nitro-assisted Brønsted acid catalysis : activation of C(sp3)–O and C(sp3)–F bonds." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF012/document.

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Les alcools sont des partenaires électrophiles attractifs pour des réactions de substitution nucléophile puisque l'eau est le seul sous-produit de la réaction en présence de nucléophiles protiques. Malgré le fait que la réaction soit fortement intéressante, la portée des transformations catalytique reste limitée à une combinaison spécifique alcool/nucléophile, ce qui rend l’emploi d’un ensemble général de conditions catalytiques fortement élusif. Cette thèse décrit le développement d'un système général de catalyse doux pour l'activation d'une large gamme d’alcools π-activés ainsi que d’alcools aliphatiques abordant ainsi les limitations clés dans le domaine. B(C6F6)3•H2O, un acide de Brønsted fort quand il est combiné avec le nitrométhane, a été découvert comme étant un système catalytique idéal pour la substitution chimiosélective d'alcools en présence de fonctionnalités et de groupements protecteurs sensibles aux conditions acides sans le compromis typique entre vitesse de réaction, réactivité substrat/nucléophile et quantité de catalyseur. Plus particulièrement, un effet co-catalytique de composés nitro est décrit pour la réaction d’azidation des alcools aliphatiques tertiaires en employant B(C6F6)3•H2O, permettant, pour la première fois, un turnover catalytique. Sur la base des investigations cinétiques, électroniques et spectroscopiques qui ont été menées, des agrégats de composés nitro et d’acides liés par des intéractions hydrogènes sont proposé comme étant l’espèce catalytiques responsables de la cinétique de la catalyse observée. L'utilité des nouvelles conditions catalytiques a été étendue au-delà de l'activation d'alcool et appliquée au clivage des liaisons fortes C-F dans les réactions de Friedel-Crafts défluorinatives de fluorures aliphatiques tertiaires<br>Alcohols are attractive electrophilic partners for nucleophilic substitution reactions as water is the only by-product in a reaction with protic nucleophiles. Despite being a highly desirable reaction, the scope of useful catalytic transformations remains limited to specific alcohol-nucleophile pairs and a general set of catalytic conditions remains elusive. This thesis describes the development of a general and mild catalyst system for the activation of a broad range of π-activated and aliphatic alcohols to address key limitations in the field. B(C6F6)3•H2O, a strong Brønsted acid, when combined with nitromethane has been found as a widely useful catalyst system for chemoselective alcohol substitution in the presence of acid sensitive functionalities and protecting groups without the typical compromises in reaction rates, substrate/nucleophile scope and catalyst loading. In particular, a co-catalytic effect of nitro compounds is described for the B(C6F6)3•H2O catalyzed azidation of tertiary aliphatic alcohols, enabling catalyst turnover for the first time. On the basis of kinetic, electronic, and spectroscopic investigations, higher order hydrogen-bonded aggregates of nitro compounds and acids are proposed as kinetically competent Brønsted acid catalysts at the origin of the enhanced reactivity. The utility of the new catalytic conditions has been extended beyond alcohol activation and applied to the cleavage of strong C–F bonds in defluorinative Friedel-Crafts reactions of tertiary aliphatic fluorides

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18

Lesieur, Pierre. "Etude de l'orientation moléculaire dans les films de Langmuir-Blodgett." Paris 6, 1986. http://www.theses.fr/1986PA066290.

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Ce travail constitue une caractérisation des films de Langmuir-Blodgett par résonance paramagnétique électrique et par diffusion Raman résonante en lumière polarisée. Les films sont constitués de multicouches, mixtes ou alternées, de porphyrines amphiphiles et d'acide docosanoïque. Le sujet porte sur l'orientation des macrocycles porphyriniques par rapport au substrat supportant les couches

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19

Gasperoni, Alessia. "Removal of inhibitors from birch pretreatment liquor by nanofiltration: Mechanisms of separation and influence of operational variables and mode." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15147/.

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Lignocellulosic biomass has attracted considerable attention as an alternative feedstock for the production of fuels, energy and chemicals, due to its renewability, abundance and reduced cost. Pretreatment and hydrolysation of lignocellulose releases sugars that are subsequently converted by fermentation. However, by-products such as aliphatic acids and furans could be generated during the upstream processes, which could inhibit enzymes and fermenting microorganisms. In addition, fermentation of low-concentrated sugars would lead to low products concentration and, consequently, to higher recovery and purification costs. Therefore, it is beneficial to reduce the concentration of the inhibitors and to concentrate the fermentable sugars in the liquor, prior to the fermentation process. This study was focused on the identification of the operating conditions to effectively remove aliphatic acids and furans from birch pretreatment liquor by nanofiltration. Two commercial NF membranes (NF90 and TS40) were employed. Effects of main operating parameters such as pH, feed concentration, temperature, pressure and tangential velocity on the separation performances were investigated, in both dead-end and cross-flow modes. The membrane performances were compared in terms of retention of sugars and inhibitors, permeate flux and permeability loss. It was found that NF90 membrane was more suitable than TS40 for simultaneous sugars concentration and beneficial removal of the inhibitors. Better separation performances were achieved at pH 1.5, 8 bar, room temperature and 3000 rpm. Dilution of 5 times of the liquor promoted the rejection of the sugars and kept low the retention of the inhibitory compounds. Water permeability loss was recovered by flushing with NaOH and water. The protocol and the operating conditions proposed in this study are suitable to perform the filtration process not only on laboratory scale, but also on industrial scale.

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20

Osei-Boadi, Kate. ""An aliphatic essential amino acid influences the expression of host defense peptides in colonic epithelial cells: in vitro findings and potential clinical implications in Crohn's disease"." Diss., Kansas State University, 2014. http://hdl.handle.net/2097/17629.

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Doctor of Philosophy<br>Department of Human Nutrition<br>Tonatiuh Melgarejo<br>Background and Objective: Crohn’s disease (CD) patients express low levels of host defense peptides (HDPs) especially β-defensins, which may compromise intestinal barrier function. Antibiotic treatment for bacterial infections in CD is limited and rarely curative, making it necessary to find alternative therapeutic approaches. We therefore investigated to what extent an essential amino acid; L-isoleucine (L-ILE) might induce the expression of human β-defensins (HBDs) in colonic epithelial cells as an alternative approach to help patients with CD. Antimicrobial activity of HBD2 was also assessed against four bacterial isolates which can cause secondary infections in CD. Methods: HTB-37 Caco-2 cells were stimulated with L-ILE at a concentration of 0 - 500µg/ml for 6 hours. Total RNA was extracted using RNeasy Micro Kit (QIAGEN). Reverse transcription was carried out with Superscript ®III First-Strand Synthesis System. The cDNA was amplified using specific primers for HBD1-3. Antimicrobial activity of HBD2 was determined using the broth dilution assay. Results: HBD1 was constitutively expressed under all conditions. HBD2 was expressed in HTB-37 cells after stimulation with L-ILE. Below 25µg/ml L- ILE stimulation, no expression of HBD2 was observed. HBD2 exhibited antimicrobial activity against bacterial isolates tested, with a MIC of 32, 64 and 128 µg/ml for both strains of E. coli, S. aureus and P. aeruginosa respectively. Conclusions: Our results indicate that L-ILE stimulation of HTB-37 Caco-2 cells can induce HBD2 expression. Data collected from our in vitro studies might have major implications for modifying the intestinal microbiota towards a healthier state in CD patients. Promoting the expression of HBD2 by colonic cells may lead to a lower rate of infection in these patients. Future in vivo studies are warranted to determine the potential clinical use of intra colonic administration of L-ILE in CD patients. The observed antimicrobial activity of HBD2 against bacterial isolates provides evidence that it is a crucial component of mucosal epithelial defense against infections which can complicate disease symptoms in CD.

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21

Malki, Abdelhafid. "Transformation électrocatalytique de produits issus de la biomasse : oxydation du fructose sur électrodes d'or et de platine." Poitiers, 1988. http://www.theses.fr/1988POIT2274.

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L'oxydation electrochimique du fructose en milieu basique et en milieu acide est realisee: une etude cinetique est effectuee, on etudie la modification des proprietes catalytiques superficielles des electrodes par adjonction d'adatomes, on fait plusieurs electrolyses a potentiel programme montrant que l'on obtient par cette reaction un melange d'acides gluconique, tartrique et citrique

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22

Muller, Michel. "Etude de reactions d'isomerisation, de cracking et d'alkylation d'hydrocarbures en presence de divers superacides." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13022.

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23

Le, Gars Pierre. "Synthese directe de chlorures d'acide par carbonylation de derives halogenes aliphatiques." Toulouse 3, 1987. http://www.theses.fr/1987TOU30199.

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24

Alami, Mouâd. "Addition conjuguee de composes organomanganeux sur divers composes carbonyles alpha -beta ethyleniques." Paris 6, 1987. http://www.theses.fr/1987PA066232.

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25

Peschard, Olivier. "Déconjugaison par protonation énantioselective : application à la synthèse de la vinylglycine." Rouen, 1989. http://www.theses.fr/1989ROUES017.

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26

Dubois, Joëlle. "Contribution a l'etude du mecanisme de la carboxylation dependant de la vitamine k." Paris 6, 1987. http://www.theses.fr/1987PA066346.

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27

HOUTTEVILLE, MARIE-CLAIRE. "Etude de la simple et de la double diastereoselectivite de la reaction d'aldolisation de l'acide propanedithioique : synthese de beta-oxodithioesters par oxydation chimioselective de beta-hydroxydithioesters." Caen, 1988. http://www.theses.fr/1988CAEN2006.

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28

Gravier-Pelletier, Christine. "Synthese du leucotriene enantiomeriquement pru ltb quatre et d'un analogue a partir du d-manniotol." Paris 6, 1986. http://www.theses.fr/1986PA066507.

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29

IZNADEN, MOHAMMED. "Esters d'acides 2h-perfluores : synthese et reactivite." Reims, 1989. http://www.theses.fr/1989REIMS001.

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Les esters d'acides hydro-2 perfluores sont prepares par defluoration photoreductive des esters perfluores correspondants dans l'hexamethylphosphorotriamide. Les proprietes acides de l'hydrogene porte par le carbone-2 ont ete exploitees et des syntheses a haut rendement de composes polyfluores multifonctionnels ont ete realisees: enaminoesters, iminoesters, cetoesters, composes heterocycliques

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30

Mayoungou-Vembet, Pierre. "Dynamique et processus d'évolution d'un hydrocarbure (eicosane) dans le sol." Poitiers, 1989. http://www.theses.fr/1989POIT2277.

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31

Coetzee, Jacorien. "Towards new catalytic systems for the formation of methyl methacrylate from methyl propanoate." Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/2585.

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The two stage Lucite Alpha Process for the industrial manufacturing of methyl methacrylate (MMA) represents one of the most efficient technologies currently available for the large scale production of this important chemical commodity. The second stage of this process, which involves the condensation of methyl propanoate (MeP) with formaldehyde over a heterogeneous fixed bed catalyst, however, still shows great scope for improvement. Herein the development of a novel homogeneous catalytic system that would promote the condensation of either propanoic acid or MeP with formaldehyde is explored. Since C–C bond forming reactions which proceed via C–H activation pathways typically display high atom efficiency, our efforts were particularly focussed on employing a functionalisation strategy that is mediated by C–H activation. In the case of propanoic acid, the possibility of achieving regioselective α-methylenation by linking the substrate to phosphorus was evaluated. Thus, a series of acyloxyphosphines and acylphosphites derived from either propionic acid or phenylacetic acid was prepared and, where stability allowed, fully characterised. Some of the resultant simple mixed anhydrides posed problems relating to their stability, and the stabilisation of such ligand systems by using electronic and / or steric effects was therefore explored. In addition, the coordination chemistry and in solution behaviour of Rh(I) and Ru(II) complexes containing these ligands was examined. Similar to the free ligands, complexes derived from these mixed anhydrides rearranged in solution via a number of decomposition pathways, with the specific pathway dependent on the nature of the auxiliary ligands. For most of these complexes, however, ligand decarbonylation was the route of preference for decomposition. Despite the instability of these complexes, a selection of Rh(I) mixed anhydride complexes were assessed for their potential as C-H activation catalysts in reactions aimed at the α-methylenation of saturated carboxylic acids. Furthermore, the stabilisation of Rh(I) mixed anhydride complexes with chelating auxilary ligands, such as bisphosphines or N-substituted diphosphinoamines, was explored. In particular, a series of new Rh(I) mixed anhydride complexes containing dppe, dppb and dppbz as secondary ligands were prepared and the effects of these secondary ligands on the in solution stability of these complexes assessed. As MeP represents the final product in the first stage of the Alpha process and not propanoic acid, the utilisation of PNP iridium pincer complexes in the regioselective sp³ C–H activation of MeP and related esters was also examined. The factors that govern the regioselectivity of such reactions were of great interest to us and, in particular, the effects of water on the reactivity and regioselectivity of these reactions were explored. For MeP, preferential C–H activation of the methoxy group was found to proceed under anhydrous conditions and the catalytic functionalisation of this site with ethene using this activation approach was considered. Formaldehyde, employed in the second stage of the Alpha process, is a difficult substance to manufacture and handle, especially on a large scale. A preliminary study on the in situ production of anhydrous formaldehyde via the catalytic dehydrogenation of methanol was therefore performed. During this study, catalytic systems based on carbonate salts and / or transition metal complexes were considered. In the hope of reducing the number of steps required in the production of MMA, a new one-pot cascade reaction for the indirect α-methylenation of MeP with methanol was developed. Although the production of MMA using this system only proceeded with low efficiency, the obtained results serve as an important proof of concept for future developments in this area. Finally, the capacity of a series of simple bases to catalyse the condensation of MeP with formaldehyde was assessed as part of a fundamental study directed towards determining the factors that govern the efficiency of this reaction. In addition, the extent to which each base effects the deprotonation in the α-position of MeP was determined with the aid of deuterium labelling experiments. Similarly, using sodium propanoate as model base a rough estimate of the kinetics of deprotonation could be made based on the degree of deuterium incorporation over time. These studies suggested that the low efficiency of this condensation reaction is not caused by ineffective deprotonation but rather by the weak nucleophilicity of the generated carbanion. For this reason, attempts to increase the electrophilicity of formaldehyde through Mannich-type condensations reactions involving secondary amine and carboxylic acid additives were made.

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32

Brechot, Philippe. "Oxycarbonylation des olefines en presence de nitrites d'alkyle catalysee par les complexes du palladium." Paris 6, 1988. http://www.theses.fr/1988PA066107.

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33

Åkerblom, Denize, and Erik Göranzon. "Greener Water Repellency? Feasible alternatives to fluoro chemicals for DWOR treatments on textiles." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-17695.

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BACKGROUND: Perfluorinated compounds (PFCs) have been used as durable water and oil repellent treatments in clothing for more than 50 years. The reason for its popularity is related to the chemical structure, which also makes these compounds persistent in the environment. Numerous studies have shown negative environmental and health effects related to high concentrations of perfluorinated compounds in blood serum. Due to these studies, this paper aimed to find out if perfluorinated compounds could be replaced by non-perfluorinated without compromising performance related to water and oil repellency. METHODOLOGY: A reference sample impregnated with fluorocarbons was compared with the following non-perfluorinated treatments, aliphatic polyurethane (comb polymer) organic silicone and acid (comb polymer) and hydrocarbon (dendrimer). Impregnations were subjected to abrasion, UV-radiation and washing and after each destructive treatment; oil and water repellency tests were conducted. The environmental and health effect of all treatments were examined in a theoretical study. RESULTS: Due to difficulties with the impregnation process, comparable results could only be concluded with the perfluorinated and the hydrocarbon compound. The hydrocarbon was superior the perfluorinated compound to abrasion but for usage simulation methods that allowed chemical reactions, hence UV-radiation and washing, the fluorocarbons showed better resistance. CONCLUSION: Results show that the hydrocarbon treatment could replace perfluorinated treatments commercially when only water and not oil repellency is required. The alternative treatments in this study are not yet sufficiently examined with respect to environmental and health and can therefore not be called greener with certainty.<br>Program: Textilingenjörsutbildningen

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34

EL, JAZOULI MUSTAPHA. "Formation de liaisons carbone-carbone par l'intermediaire des imidothioesters : applications synthethiques." Caen, 1985. http://www.theses.fr/1985CAEN2016.

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Apres une etude de la metallation, suivie d'alkylation, de quelques imidothioesters satures, des reactions d'aldolisation dont la selectivite est examinee, sont realisees a partir d'un n-phenyl imidothioester. Les imidothioesters alpha -insatures dont la reactivite vis-a-vis de magnesiens et de lithiens est etudiee sont de bons accepteurs de michael. Par l'intermediaire des alkylthio-enaminates et d'une cetenimine issue de leur decomposition thermique, de nouvelles voies d'acces a des cetones dissymetriques, sont decrites a partir de n-phenyl imidothioesters satures et alpha -insatures. Synthese de cetones terpeniques et d'une pheromone

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35

Girardin, André. "Nouvelle voie d'acces stereospecifique a la vitamine a, l'acide retinoique et son isomere 13-cis : synthese d'analogues." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13157.

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Les acides retinoiques all trans et 13-cis offrent un grand interet dans le domaine medical, en particulier pour le traitement de maladies de la peau. En vue d'obtenir des structures offrant un meilleur indice therapeutique, differents analogues de l'acide retinoique ont ete synthetises. Dans une premiere partie, une synthese originale de chromannes est decrite. Dans une seconde partie, les analogues sont prepares par reaction de wittig mais il s'avere que la purification des isomeres est extremement difficile. En vue de supprimer le probleme de la separation, il a ete realise une etude utilisant le titane a degre d'oxydation zero. Il a ete montre que l'utilisation de cette nouvelle methode permettait de preparer une chaine polyenique all trans ainsi qu'une chaine polyenique presentant un maillon cis terminal. Cette methode a ete utilisee pour preparer des exemples en serie terpenique ainsi qu'en serie aromatique

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36

Dlubala, Alain. "Etude de la reactivite de dianions formes par double deprotonation de dithioesters beta-thiosubstitues." Caen, 1987. http://www.theses.fr/1987CAEN2010.

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37

Magnoux, Patrick. "Modes de formation du coke et de désactivation des zéolithes : influence de la structure poreuse et de l'acidité." Poitiers, 1987. http://www.theses.fr/1987POIT2033.

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38

Pham, Thi-Nhan Nguyen. "Thio-rearrangement de claisen : facilite, reversibilite, synthese de composes thiocarbonyles." Caen, 1987. http://www.theses.fr/1987CAEN2045.

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39

Maddaluno, Jacques. "Synthèse énantiosélective de composés d'intérêt biologique : approche de polyols vicinaux par aldolisation stéréocontrôlée, approche de bêta-amino esters par addition de Michael stéréocontrôlée sous haute pression." Paris 6, 1986. http://www.theses.fr/1986PA066240.

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La réaction d'aldolisation des benzoylaryacetates avec l'acétaldéhyde fait ressortir la capacité de ce synthon à effectuer un transfert d'asymétrie. Etude de la réactivité des alcoxy-3 acroléines. L'addition d'amines primaire sur des crotonates à haute pression permettent d'obtenir de meilleures sélectivités

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40

Gaudin, Jean-Marc. "Synthèses sélectives à l'aide de complexes du Palladium(0) : élaboration de chaine latérale de stéroïde (glaucastérol), phéromones et alpha-amino esters d'intérêts biologiques." Paris 6, 1986. http://www.theses.fr/1986PA066536.

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Ce travail porte sur l'utilisation de complexe du palladium (0) en catalyse homogène pour la synthèse de molécules d'intérêts biologiques. Trois applications y sont décrites: - la synthèse d'une phéromone secrétée par la reine des abeilles et d'une hormone végétale : l'acide traumatique. La construction du squelette carbone de ces molécules est basée sur une double alkylation d'une bis (aryl sulfonyl) méthane, l'une d'entre elles faisant intervenir un complexe eta (3) allyl palladien fonctionnalisé ; - la synthèse d'alpha-amino esters susceptibles d'être utilisés comme inhibiteur d'enzyme. Ceci est réalisé par l'alkylation catalysée d'une base de Schiff dérivée de la glycine. Quelques facteurs pouvant influencer l'énantiosélectivité de cette réaction ont été étudiés; - la synthèse de la chaine latérale du glaucasterol. Ce stéroïde marin isolé très récemment à la particularité de posséder dans sa structure un cyclopropane vinylique. La réaction clef est une cyclisation sn' catalysée. Elle s'effectue avec un transfert complet de la chiralité d'un benzoate allylique sur un des carbones cyclopropaniques et permet d'autre part le contrôle de la stéréochimie de la double liaison.

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41

Denys, Goument Colombe. "Dicétones-1,4 thiosubstituées." Rouen, 1988. http://www.theses.fr/1988ROUES023.

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42

Dupas, Georges. "Synthèse et réactivité de modèles du NADH : modèles chiraux, modèles greffés." Rouen, 1987. http://www.theses.fr/1987ROUES007.

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43

Potin-Gautier, Martine. "Photoamidation d'olefines fluorees, en milieu homogene et en milieux microemulsions non aqueux." Toulouse 3, 1987. http://www.theses.fr/1987TOU30011.

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Les amides perfluores et mixtes (a doubles chaines hydrogenee et perfluoree) sont des precurseurs de tensioactifs susceptibles d'ameliorer les proprietes des mousses extinctrices, par diminution de la tension interfaciale entre l'eau et l'huile par un meilleur etalement de la mousse. Ces amides sont synthetises par photoamidation d'olefines : r::(f)-ch=ch::(2), r::(f)-ch=ch-r::(h), r::(f)-ch::(2)-ch=ch-r::(h) dans le t-butanol et dans des microemulsions de formamide

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44

Ferroud, Clotilde. "Étude de la réaction de Diels-Adler intra et intermoléculaire sous haute pression : application à la synthèse stéréosélective d'alcaloïdes de l'indole du groupe des yohimbanes." Paris 6, 1986. http://www.theses.fr/1986PA066023.

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Le schéma de synthèse repose sur une unité bicyclique, précurseur direct des unités (d,e) du squelette pentacyclique. Cet intermédiaire est basé sur une réaction de Diels-Alder sous haute pression, utilisant la cycloaddition de diènes de structure donneur-accepteur 1,4 avec une lactone insaturée comme diénophile. La synthèse du système pentacyclique est exposée à partir de cet intermédiaire clé.

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45

Wasser, Christian. "Synthese de derives phenoliques et etude de leur proprietes hypopigmentantes." Université Louis Pasteur (Strasbourg) (1971-2008), 1987. http://www.theses.fr/1987STR13191.

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Ce memoire presente les syntheses d'acyl-2 methoxy-4 phenols (a) d'alkyl-2 methoxy-4 phenols (b), d'alkyl-3 methoxy -4phenols (c), d'alkoxy-4 phenols (d) d'acide (hydroxy-4' phenyl)-3 methyl-2 propionique (e), d'acide (hydroxy-4' phenyl)-3 hydroxy-2 propionique, d'hydroxy-7 carboxy-3 tetrahydro-1,2,3,4 isoquinoleine et d'acide hydroxy-4 phenylpropargylique(f). L'etude "in vivo" (cobayes) et "in vitro" des proprietes hypopigmentantes des composes a, b, c, d, e et f. L'etude "in vivo" et "in vitro" des proprietes hypopigmentantes de substances naturelles : arbutine, luteoline, abscissine

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46

Lavigne, André. "Oxydations cupro-catalysees des amines aliphatiques : etudes mecanistiques et applications synthetiques." Paris 6, 1987. http://www.theses.fr/1987PA066470.

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Preparation de nitriles a partir d'amines primaires et d'alpha -aminoacides. Les acides amines monosubstutitues rch(nh::(2))co::(2)h donnent le nitrile rcn, alors que les acides amines disubstitues rr'c(nh::(2))co::(2)h conduisent a l'azine rr'c=n-n=cr'r. Les mecanismes proposes font intervenir le cuivre (iii), forme in situ a partir du cuivre (i) et de l'oxygene

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47

Léon, Patrick. "Alkylation d'amines par les sels de sulfonium, reaction de type gabriel et synthese de polyamines." Paris 6, 1987. http://www.theses.fr/1987PA066488.

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48

Mignard, Samuel. "Mode de désactivation des zéolithes : caractérisation des zéolithes cokées par adsorption de diverses molécules." Poitiers, 1988. http://www.theses.fr/1988POIT2297.

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49

Réau, Régis. "Phospholes et phosphanorbornadienes : valorisation en catalyse homogene." Toulouse 3, 1988. http://www.theses.fr/1988TOU30162.

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Les ligands etudies ont ete utilises d'une part en association avec des complexes cationiques du palladium en reactions de dimerisation de l'acrylate de methyle, de codimerisation de l'acrylate de methyle et du butadiene-1,3 et de telomerisation de ce dernier avec le methanol; d'autre part en association avec des complexes de rhodium dans l'hydroformylation de l'hexene-1 de styrenes et de l'acrylate de methyle

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50

Baharmast, Bahman. "Monohalogénocyclopropanation de composés éthyléniques fonctionnalisés : réactions d'élimination sur les adduits." Grenoble 1, 1986. http://www.theses.fr/1986GRE10081.

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On etudie la stereoselectivite de la reaction de monohalogenocyclopropanation menee sur des alcools, esters. , cetones et acides alpha -ethyleniques, puis la methylmonohalogenocyclopropanation des cetones et alcools alpha -ethyleniques. Dans un dernier chapitre est abordee l'etude de la regioet de la stereo elimination sur les alcools halogeno- et methylhalogenocyclopropaniques apres etude prealable sur des composes halogenocyclopropaniques apres etude prealable sur des composes halogenocyclopropaniques non fonctionnalises

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