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1
Ibanez, Sébastien. "Caractérisation physicochimique des membranes cellulaires lors de la cancérogénèse : application à la plasticité cellulaire." Thesis, Lyon, 2021. https://n2t.net/ark:/47881/m6tt4qsz.
Анотація:
Le tissu mammaire est intrinsèquement hétérogène et son développement ainsi que son homéostasie impliquent des mécanismes génétiques et épigénétiques permettant des modifications contrôlées de l’identité cellulaire tout au long de la vie d’une femme. Dans un contexte tumoral, les mécanismes liés à cette modulation de l’identité cellulaire peuvent être en revanche perturbés. Ceci facilite une grande dynamique épigénétique et l’acquisition d’une plasticité phénotypique située au cœur du développement et de la progression tumorale. La plasticité phénotypique décrit la capacité d’un système biologique à s’adapter et exprimer différents phénotypes en réponse à des conditions environnementales changeantes. Les cellules perdent dans ce contexte leur identité cellulaire et subissent des modifications profondes de leur métabolisme. L’une des conséquences de ces dérégulations métaboliques est le remodelage des lipides lors de l’acquisition d’un phénotype plastique. Nous avons pu corréler ce remodelage lipidique à une modification de la fluidité membranaire des membranes cellulaires. Cette mesure de fluidité membranaire s’effectue à l’aide d’une sonde de fluorescence ratiométrique synthétisée pour la première fois dans notre équipe. La première partie de cette thèse a concerné la validation dans un contexte biologique de la capacité de cette sonde fluorescente, le Dioll, à rendre compte de l’alignement des chaînes lipidiques directement au sein des membranes d’une cellule. L’analyse des propriétés physicochimiques de la sonde de fluorescence lors du marquage des membranes cellulaires a mis en avant les avantages de cette molécule par rapport aux sondes préexistantes, notamment un meilleur rapport quantique, une meilleure répartition au sein des phases liquides désordonnées permettant ainsi une meilleure discrimination des endomembranes et un marquage des membranes cellulaires avec une résolution sans précédent. Lors de la deuxième partie de cette thèse, nous avons utilisé les propriétés du Dioll pour mettre en évidence la corrélation existant entre fluidité membranaire et des variations phénotypiques à l’origine de la plasticité cellulaire. L’analyse d’un ensemble de lignées cellulaires cancéreuses mammaires a montré que nous pouvions discriminer les différents sous-types cellulaires à partir de ces mesures corrélées le plus souvent à une plus grande fluidité membranaire. Dans un second temps, nous avons utilisé un modèle isogénique de modulation de la plasticité cellulaire par induction d’un processus de perte des caractéristiques épithéliales au sein de cellules mammaires humaines immortalisées initialement épithéliales (HMEC). À partir de ce modèle, nous avons pu observer une diminution de l’alignement des chaînes lipidiques membranaires lors de l’acquisition d’un phénotype plus indifférencié. Finalement en modulant l’environnement hormono-nutritif de la cellule, il a été possible de créer un modèle permettant l’acquisition et la stabilisation d’un phénotype très indifférencié, hybride en termes de composante épithéliale et mésenchymateuse et multipotent. Ce phénotype dit « métastable » permet de rediriger de façon très efficace ces cellules dans les différentes voies de différenciation mammaire luminale ou myoépithéliale. Nous avons pu ainsi corréler les variations phénotypiques dans ce modèle à des variations biophysiques associées à une plus grande fluidité membranaire, les cellules métastables possédant un désordre très important au niveau de leurs chaînes lipidiques membranaires en comparaison de leur descendance ayant acquis une identité cellulaire luminale ou myoépithéliale. L’ensemble de ces résultats est discuté dans la perspective d’utiliser ces mesures indirectes de fluidité membranaire pour déterminer un indice de plasticité phénotypique ou de dynamique épigénétique qui servirait alors d’outil diagnostic et d’aide à la mise en place de stratégies thérapeutiques plus efficaces et personnaliséesThe mammary tissue is inherently heterogeneous and its development as well as homeostasis involve genetic and epigenetic mechanism allowing controlled switches of cell identity during woman’s lifetime. During tumoral context, the mechanisms linked to this cell identity modulation can be disturbed. This facilitates a large epigenetic dynamic and the acquisition of phenotypic plasticity essential for tumour development and progression. Phenotypic plasticity describes the ability of a biological system to adapt and express different phenotypes in response to variations of environmental conditions. In this context, the cells lose their cell identity and undergo profound changes in their metabolism. One of the consequences of these metabolic dysregulation is the remodelling of cell lipid composition during the acquisition of a plastic phenotype. We were able to correlate this lipid remodelling with a change in lipid chains arrangement within cell membranes, a phenomenon known to modify the membrane fluidity. The membrane fluidity is measured by a ratiometric fluorescent probe synthesized for the first time in our team. The first part of this thesis concerned the validation in a biological context of this probe, Dioll, to report its capacity of following the membrane fluidity of cell membranes. The analysis of the physicochemical properties of the fluorescent probe during the labeling of cell membranes has highlighted the advantages of this molecule compared to pre-existing probes (better quantum ratio, better distribution within disordered liquid phase and better discrimination of endomembranes). The second part of this thesis, we used the properties of Dioll to highlight the correlation between membrane fluidity and phenotypic variations at the origin of cell plasticity. Analysis of a set of breast cancer cell lines showed that we could discriminate different cell subtypes. Secondly, we used an isogenic model of modulation of cellular plasticity by inducing a process of loss of epithelial characteristics within initially epithelial immortalized human mammary cells (HMEC). From this model, we were able to observe an increase of membrane fluidity during the acquisition of a more undifferentiated phenotype. Finally, by modulating the hormonal-nutritive environment of the cell, it was possible to create a model allowing the acquisition and stabilization of a much undifferentiated phenotype, hybrid in terms of epithelial and mesenchymal component and multipotent. This so-called “metastable” phenotype makes it possible to redirect these cells into the various luminal or myoepithelial mammary differentiation pathways. We were thus able to correlate the phenotypic variations in this model with biophysical variations associated with greater membrane fluidity, the metastable cells having a very significant disorder at the level of their membrane lipid chains in comparison with their progeny having acquired a luminal cell identity or myoepithelial. All of these results are discussed with a view to using these measurements of membrane fluidity to determine an index of phenotypic plasticity or epigenetic dynamics which would then serve as a diagnostic tool and aid in the implementation of therapeutic strategies more efficient and personalized
2
Roggenbuck, Rafael. "Darstellung von Sauerstoff-Heterocyclen durch rhodiumkatalysierte Tandem-Hydroformylierung von ungesättigten Alkoholen." [S.l. : s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962720844.
3
Dieme, Jean-Louis. ""La mort diola" (ou la seconde naissance) : esquisse des éléments d'une anthropologie et d'une théologie diola de la mort." Paris 4, 1988. http://www.theses.fr/1987PA040316.
Анотація:
Comment l'homme diola conçoit-il la mort ? Pour l'homme diola du pays gassylai, brin ou bandial en Casamance (Sénégal), la mort est conçue comme un grand passage, un grand voyage, une grande traversée. La vie et la mort constituent, pour lui, une seule et même réalité vivante qui porte deux noms différents et se manifeste sous deux visages différents. La mort est un autre nom, une autre réalité de la vie. La mort, c'est l'autre vie ; et le mort, un autre vivant. Celui ou celle qui meurt entreprend un grand voyage qui lui permet de passer d'un monde à un autre. Il passe du monde visible au monde invisible. Le premier monde, le monde visible, est celui des hommes ; le second, le monde invisible, est celui des morts et des ancêtres. Dieu, quant à lui, habite, à la fois, le monde visible et le monde invisible, parce qu'il en est l'unique créateur, le pie-mère de tous les hommes et de tous les vivants, le maitre de la vie et de la mortHow does the diola man conceive death ? For the diola man of the gassylai country side, brin or bandial in Casamance (Senegal), death is conceived like a great passage, a great voyage, a great crossing. Life and death constitute for him one and the same living reality which has got two different faces. Death is another name, another reality of life. Death is another life and dead is another living. He who dies undertakes a great voyage which permits him to go over from one world to another. He passes from the visible world to the invisible world. The first, the visible world, is the one of men; the second, the invisible world, is the one of the dead and of the ancestors. God, as for him, lives both in the visible world, for he is their sole creator, the father and mother of all the men and the living, the master of life and death
4
Cullen, Bernard. "Selective hydrogenation of a multifunctional compound : 2-butyne-1,4-diol to cis-2-butene-1,4-diol." Thesis, University of Glasgow, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412969.
5
Mpuhlu, Batsho. "Synthesis of P-Methane-3,8-Diol." Thesis, Nelson Mandela Metropolitan University, 2007. http://hdl.handle.net/10948/570.
Анотація:
The synthesis of para-menthane-3,8-diol in a batch reactor was investigated in some detail with the view to evaluate the potential of producing said p-menthane- 3,8-diol in a continuous-flow reactor from the results obtained from the batch process. The methodology used as base for this investigation was a published procedure by Takasago of Japan. The Takasago-method produced 92.3 percent Yield for the product para-menthane-3,8-diol, and 2.7 percent Yield of the by-product, acetal. The objective for this investigation was to produce a minimum p-menthane-3,8- diol content of 97.0 percent and a maximum content of 3.0 percent for the by-product acetal. The batch production process was evaluated in detail using statistical experimental design methodologies. Three process variables, namely catalyst loading, organic/aqueous phase ratio and reaction temperature were selected for the study. The experimental method was based on the Takasago procedure, however the substrate was added as a single slug as opposed to gradual addition method and the reaction period was reduced to 30 minutes. Apart from statistical analysis, mechanistic aspects were also used to interpret the following results. Using a central composite design, three response models (one for the conversion of citronellal, p-menthane-3,8-diol and acetal formation) were determined. An analysis of the response surfaces indicated that, to increase the citronellal conversion all three variables should be increased. To increase the amount of pmenthane- 3,8-diol, the reaction temperature and acid concentration should be increased, but the Aq/org ratio should be decreased as the acid catalyst concentration is increased. To minimize the amount of acetals formed during the reaction, the Aq/org ratio should be decreased; temperature and acid concentration can be decreased or increased. The reaction mechanism suggested that p-menthane-3,8-diol may be formed along two pathways: One pathway directly forms p-menthane-3,8-diol, whilst the second pathway forms the isopulegol first, then proceeds to form product by hydrolysis. The acetal is formed as result of the reaction between unreacted citronellal and p-menthane-3,8-diol. From the design experiments it was suggested that reaction time can be reduced to 8 minutes at reaction temperatures between, 80-85 0C The product and acetal were isolated by simple vacuum evaporation of the low boiling citronellal and isopulegol. Results from recycling the catalyst phase were similar to those of the initial process. The results of this investigation has clearly shown that with a proper understanding of the effect of process variables on the performance of the batch synthesis route, the conversion of this traditionally batch (actually semi-batch) process into a continuous process is quite feasible provided that suitable equipment is available. The most important features required for such equipment would be: Intense mixing throughout the reaction zone so as to maximise the surface area between the two immiscible phases, hence the rate of mass transfer between the two phases; and the ability to run reactions above the boiling point of water. Plans for the further study of the process are already well underway and sections of static mixing tubes have been acquired to build a continuous lab scale tubular reactor that would be capable of providing the level of mixing required.
6
Seoane, Gustavo A. "Synthesis of pyrrolizidine diols via azide-diene cycloadditions." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/81012.
Анотація:
The generality of the [4+1] annulation methodology in the context of natural product synthesis was demonstrated by extending its applicability to the heteroatom (nitrogen) case thus allowing access to the alkaloid field. This novel methodology involved the intramolecular union of a hypovalent nitrogen atom equivalent and a conjugated diene to afford a pyrroline ring. The flexibility of this strategy was exemplified by the formal synthesis of ring-A oxygenated pyrrolizidine alkaloids platynecine 8, turneforcidine 9, hastanecine 10, and dihydroxyheliotridane 11.
The key features of this technology involved preparation of azidodiene ill, its cyclization, via the intermediate triazoline which was not isolated, to vinylaziridines 234, and the vinylaziridine-pyrroline rearrangement of several derivatives of 234 to pyrrolizidines 239, 241, and 242. A study of the thermal decomposition of oxygenated azidodienes such as 196 and 233 was carried out. Conclusive results regarding the stereochemical control of the C-7 substituent were attained and used for the formal stereospecific syntheses of pyrrolizidinediols 8, 9, 10, and 11.
The possibility of asymmetric induction was also investigated, and was realized in the microbial reduction of only one of the enantiomers of alcohol ill protected as ester 248, providing potential access to either enantiomeric series of pyrrolizidine diols.
[see document for diagram of chemical reaction]Ph. D.
7
Ayari, Abdelhamid. "Synthèse et réactivité de diols-1,2 F-alkylés." Nice, 1989. http://www.theses.fr/1989NICE4336.
Анотація:
Le travail réalisé concerne la synthèse et la réactivité de F-alkyl ethanediols-1,2 de structure générale R indice F CHOHCH indice2 OH. Le matériau de départ est constitué par les F-alkyléthenes R indice F,CH=CH indice 2. Ces diols sont caractérisés par la présence d'un groupement hydroxyle adjacent à la chaine fluorée. Ils sont susceptibles de présenter des propriétés particulières dues à la réactivité, a priori, différentes des deux fonctions alcools. A partir d'alcènes, trois voies de synthèse ont été testées : oxydation par le permanganate de l'hexadecyltrimethyl ammonium dans du cichlorométhane ; oxydation par le permanganate de potassium dans un système binaire : eau-éthanol et en présence de 5% d'Aliquat 336 ; oxydation par le permanganate de potassium dans de l'acétone. Quatre familles de produits issus de la réactivité de ces F-alkyl-ethanediols-1,2 nous ont paru très prometteurs : 1) l'azoture de F-alkyl-2 hydroxy-2 éthane; 2) le méthacrylate de F-alkyl-2 hydroxy-2 éthyle ; 3) l'oxyde d'allyle de F-alkyl-2 hydroxy-2 éthyle ; 4) les sels d'ammonium. Ces ammoniums sont susceptibles, a priori, de mettre en solution dans l'eau aussi bien des hydrocarbures que des fluorocarbures ; de conduire à des mousses stables et de moduler l'hydrophobie considérable de la chaine fluorée
8
Reeve, Toby Benjamin. "Diol-functionalised polystyrene resins : synthesis and applications." Thesis, University of Leicester, 2004. http://hdl.handle.net/2381/30088.
Анотація:
Chapter 1 introduces the motivation behind and the methods for the use of insoluble polymers for the heterogenisation of well-defined homogenous catalysts. The use of diol ligands and polymer-supported catalysts in the Diels-Alder reaction and dialkylzinc addition to aldehydes is also reviewed. Finally, the aims of this work are outlined. Chapter 2 evaluates various routes for the synthesis of diol-functionalised resins. The grafting of triol compounds to preformed chloromethylated resins was undertaken through formation of an ether linkage, leaving a pendant diol. Emphasis was placed on incorporating an alkyl spacer between the diol moiety and the resin in order to distance the supported Lewis acid from the polymer matrix in subsequent catalysis applications. A relationship between the size of alcohol substrates and ease of reaction with chloromethylated resins is reported; due to mass transport effects, the grafting of larger residues is considerably more difficult. Chapter 3 discusses the synthesis of polystyrene resins possessing a chiral diol-functionality introduced via asymmetric dihydroxylation of alkenes. The asymmetric dihydroxylation process is reviewed. Two contrasting strategies for diol-functionalised resin preparation are described: (a) solution-phase alkene dihydroxylation followed by grafting and (b) dihydroxylation of an alkene moiety already bound to the solid-phase. Chapter 4 investigates supported-diol-titanium species as Lewis acids and probes the effect of alkyl spacer length on their activity in the Diels-Alder reaction of methyl acrylate and cyclopentadiene. The incorporation of a nine-carbon methylene spacer led to an improvement in catalyst activity. The application of polymer-bound Ti-based Lewis acids in the asymmetric Diels-Alder reaction of methacrolein and cyclopentadiene and diethylzinc addition to benzaldehyde is also reported. In both cases low ee's were observed.
9
Xu, Su-Ying. "Supramolecular systems for diol and fluoride recognition." Thesis, University of Bath, 2014. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.642049.
Анотація:
Determination of a target molecule is of great importance both in industrial applications and human health. For a long time, this has attracted the extensive attention of researchers to develop new strategies. One of the vigorous sub-branches lies in supramolecular field. its ability to mimic a natural occurring event and unearth the mode of interaction for a targeted molecule. By varying the structure of a probe, researchers could rationally design synthetic sensors with selective binding affinity to target molecules and also satisfy different requirements for a certain application by combining different functional groups. The growing incidence of diabetes has promoted scientists to develop new effective strategies for early and quickly monitoring saccharide concentration. Interest in boronic acid-based saccharide probes has dramatically increased in the past several decades due to the unique properties of forming boronate esters with cis-diols. Previous work in James group demonstrated that by the introduction of a proximal amine group, the binding between boronic acid and saccharide can occur at neutral, i.e., physiological pH and the binding between boronic acids and saccharides can induce fluorescent "turn-on" responses. Acrylamide hydrogels with boron-additives have potential applications in separating saccharides and recognising glycation process in electrophoresis. Two monoboronic acid-based gel monomers 27 and 28 with different fluorophores have been synthesised and analysis measurements were carried out both in hydrogel, as well as in solution. As a Lewis acid, the strong binding affinity between boron and fluoride was also extensively explored to develop fluoride sensors. By investigating boron-containing 1,8-naphthalimide derivative 33, it is found that the binding between boron and fluoride could induce a red-shift of absorption (about 20 nm) with obvious colour changes and unique changes of NMR chemical shift. By comparison with control compounds (34 and 35), it was found that the addition of the boronic acid moiety would improve the selectivity, though at the expense of loss of sensitivity towards anions. Traditional molecular recognition is mainly based on host-guest interaction, where a synthetic host molecule could selectively interact with a guest molecule via weak and generally reversible interactions. The reaction-based sensing strategy is a new strategy in designing a high sensitivity probe toward a specific analyte, in which an irreversible reaction is normally utilised. Boronic acid moieties were extensively used both in exploring saccharide sensors and organic synthesis (Suzuki Homocoupling reaction). Here these two aspects were combined together to develop a Suzuki Homocoupling reaction-based saccharide sensing strategy. Different boronic acid substrates were employed and the sensing mechanism was investigated. Furthermore, as a collaboration project, colorimetric enantioselective recognition of chiral secondary alcohols was achieved via hydrogen bonding to a chiral metallocene containing chemosensor (38 and 39).The observed enantioselectivity of 38 could partly be due to the steric effect of the formed hydrogen bond complexes and the distance to the chiral centres.
10
Barbour, Leonard James. "Clathration by diol hosts : thermodynamics and structure." Doctoral thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/21427.
Анотація:
Inclusion properties of the following seven diol host compounds were investigated: Host 1 9,9'-bis(9,91-dihydroxy-fluorene) Host 2 1, 1'-binaphthyl-2,2'-bis( diphenylhydroxymethyl) Host 3 2,2'-bis(9-hydroxy-9-fluorenyl)biphenyl Host 4 trans-9, 10-dihydroxy-9,10-diphenyl-9, 10-dihydroanthracene Host 5 trans-9, 10-dihydroxy-9,10-di-p-tolyl-9,10-dihydroanthracene Host 6 trans-9, 10-dihydroxy-9, 10-di-p-tert-butylphenyl-9, 10-dihydroanthracene Host 7 trans-9, 10-dihydroxy-9, 10-di-a-naphthyl-9, 10-dihydroanthracene These compounds all possess molecular planes with bulky substituents and opposing hydroxyl moieties as probes for possible coordination to guest molecules by means of hydrogen bonding. Sixteen different inclusion compounds were formed with common organic solvents as the guests. Various characterisation techniques were used and the crystal structures of the inclusion compounds and of the a-phases of Hosts 2 and 5 were elucidated using single crystal X-ray diffraction methods. Thermal decomposition studies using thermogravimetry and differential scanning calorimetry (DSC) were carried out in order to relate the strength of the host-guest interactions to the structures of the inclusion compounds. Owing to practical limitations, the DSC technique is not suitable for the measurement of '1H for the decomposition of an inclusion compound where the guest is relatively volatile. Therefore an apparatus was devised to yield accurate '1H0 values for this process.
11
Su, Hong. "Structure and decomposition of diol inclusion compounds." Master's thesis, University of Cape Town, 1998. http://hdl.handle.net/11427/27009.
Анотація:
The inclusion properties of the host, trans-9, 10-dihydroxy-9, 10-diphenyl-9,10- dihydroanthracene, with various guest molecules, namely cyclohexanone, 2- methylcyclohexanone, 3-methylcyclohexanone and 4-methylcyclohexanone, were investigated. The host to guest ratios were determined by programmed temperature thermogravimetry. Two of the four molecular structures were elucidated using single crystal X-ray diffraction. All the inclusion compounds were also characterised by differential scanning calorimetry, hotstage microscopy and Xray powder diffraction. The kinetics of decomposition of the inclusion compound containing the guest cyclohexanone were studied using different experimental techniques under isothermal conditions: these were the quartz microbalance, the levitating balance and isothermal thermogravimetry. The kinetics of decomposition of the other three compounds were studied by means of isothermal thermogravimetry. The Arrhenius parameters determined showed a compensation effect between the activation energies and pre-exponential factors. Competition experiments were performed to determine the selectivity of the host for the four guest substances.
12
Schubert, Wolf-Dieter. "Structure and thermodynamics of Diol inclusion compounds." Master's thesis, University of Cape Town, 1991. http://hdl.handle.net/11427/16007.
Анотація:
Includes bibliographical references.This work is predominantly concerned with the structural analysis of the coordinatoclathrates formed by the host compound trans-9,10-dihydroxy-9,10-diphenyl- 9,10-dihydroanthracene (1) with compounds containing neutral nitrogen atoms (Lewis bases). The structures of inclusion compounds with two nitriles (acetonitrile and 3- hydroxypropionitrile), with pyridine and with three substituted pyridines (3- methylpyridine, 2,4-dimethylpyridine and 2,6-dimethylpyridine) have been solved by single crystal X-ray diffraction methods. The crystal packing modes and hydrogen bonding schemes have been elucidated, while the guest cavities have been investigated. The thermal stability of the complexes was analysed by thermogravimetric analyses and differential scanning calorimetry. These techniques were employed in determining the guest content, in investigating the thermal properties of the compounds and in establishing the activation energies for the desorption processes. Desorption studies, utilising X-ray powder diffraction, were used to investigate the structures resulting from the desorption of guest from the complexes. The selectivity of the host for either of the isomers 2,4- and 2,6-dimethylpyridine was investigated.
13
Gooden, Peter N. "Continuous-flow reactions of diols in supercritical carbon dioxide." Thesis, University of Nottingham, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580384.
Анотація:
The continuous O-alkylation of alcohols and diols has been studied over solid acid catalysts in supercritical carbon dioxide, scC02, to examine the potential for performing highly selective, clean etherification reactions. An introduction to the application of these reactions with respect to green chemistry is presented in Chapter 1, focusing in particular, on the industrial use of alternative solvents and solid acid catalysts. The apparatus, experimental methods and analytical techniques are described in Chapter 2, and their use is illustrated with reference to the acid catalysed esterification of 1,6-hexanediol in SCC02. Chapter 3 details the etherification of the symmetrical diol substrate, 1,6-hexanediol, which was investigated using primary alcohols (MeOH, EtOH and n-PrOH) as alkylating agents. This system showed remarkable pressure tunability with the desymmetrised mono-ether being favoured at high system pressures, and the bis-ether formed selectively at low pressure. When studying other diols, intermolecular etherification was only observed at primary OH groups, secondary OH groups preferentially underwent elimination or formed cyclic ethers when the substrate structure allowed. The etherification of the commercially important di-hydroxy substrate, isosorbide, was also attempted in scC02, and the results are presented in Chapter 4. The OH groups of isosorbide, an unsymmetrical molecule, exhibited vastly differing reactivity, and achieving good selectivity to the desired product, dimethyl isosorbide (DMI), proved difficult. In addition, the formation of dimethyl ether (DME), an undesirable by-product formed from unreacted MeOH, means that these processes currently have limited commercial potential. Dimethyl carbonate (DMC) has also been studied as a potentially benign reagent for the formation of methyl ethers in scC02, shown in Chapter 5. DMC was observed to decompose over acid catalysts to form DME and C02, but gave excellent yields of the methyl ethers of various substrates. Temperature programmed experiments revealed that the decomposition reaction greatly assisted the methylation of the substrate. This system shows much greater potential for commercial application as highly concentrated substrate solutions can be converted with high yields and selectivities. A brief summary of the conclusions drawn from this Thesis is given in Chapter 6. This Chapter evaluates how well the initial Project aims were met and proposes some future directions for this area of research.
14
Herman, Thierry. "Acylation et silylation énantiosélectives de diols méso ou prochiraux." Grenoble 2 : ANRT, 1988. http://catalogue.bnf.fr/ark:/12148/cb37614250n.
15
Liu, An. "Ferriin oxidation of benzylic 1,2-diols a mechanistic approach /." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=861.
16
Herman, Thierry. "Acylation et silylation énantiosélectives de diols méso ou prochiraux." Rouen, 1988. http://www.theses.fr/1988ROUES020.
17
Irish, Kerry E. "Clarence Dill : the life of a western politician /." Thesis, Connect to this title online; UW restricted, 1994. http://hdl.handle.net/1773/10494.
18
Harvey, Grant Andrew. "Structure and reactivity of diol host-guest compounds." Master's thesis, University of Cape Town, 1990. http://hdl.handle.net/11427/17286.
Анотація:
Includes bibliographical references.The crystal structures of trans-9, 10-dihydroxy-9, 10-diphenyl-9, 10- dihydroanthracene with various guest molecules have been determined by X-ray diffraction. The guests were 2-butanone, 4-vinylpyridine, 4-methylpyridine and 2-methylpyridine. The host to guest ratios were determined by microanalysis and density measurements. The change of the overall host lattice structure upon guest release was studied by X-ray powder diffraction. The thermal characteristics of the compounds were studied using thermogravimetric analysis and differential scanning calorimetry. Guest desorption from three of the four compounds occurred in a single step whereupon the host framework collapsed back to the guest-free structure. The compound containing 4-methylpyridine, released the guest molecules in a two-step process. Evidence of a new host phase was identified from the XRD pattern of this intermediate phase. On further guest release, the intermediate phase converted to the guest-free host structure. In an attempt to reconcile thermodynamics with structure, the correlation between hydrogen bond length and guest desorption enthalpy was investigated.
19
Niang, Aliou Cissé. "Faith and freedom in Galatia a Senegalese Diola sociopostcolonial hermeneutics /." Fort Worth, Tex. : Texas Christian University, 2007. http://etd.tcu.edu/etdfiles/available/etd-02012008-150123/unrestricted/Niang.pdf.
Анотація:
Thesis (Ph.D.)--Brite Divinity School, Texas Christian University, 2007.Title from dissertation title page (viewed Feb. 4, 2008). Includes abstract. "Dissertation presented to the Faculty of the Brite Divinity School in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Biblical interpretation." Includes bibliographical references.
20
Farren, Christopher. "Polyfluorinated compounds via free-radical reactions of alcohols and diols." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4791/.
Анотація:
Site-selective incorporation of fluorocarbon substituents into organic molecules is a field of continuing interest, and a variety of approaches have been reported. The research described within this thesis is concerned with the functionalisation of C-H bonds adjacent to primary or secondary hydroxyl units via free-radical additions to fluoroalkenes. A range of cyclic and acyclic alcohols and diols have been functionalised in this manner, and both substituent and electronic effects on the radical process have been investigated. Further functionalisation of the polyfluoroalkylated products has been performed, giving a range of new fluorinated systems, and an investigation into the chemistry of these systems has begun.
21
Díaz-Urrutia, Christian. "Vanadium-Catalyzed Aerobic Oxidation of Diols and Lignin Models/Extracts." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35102.
Анотація:
As the world moves forward to the development of biorefineries, the interest to replace chemicals and materials derived from petroleum is increasing exponentially. Lignin is a macromolecular by-product derived from the wood pulping industry, mainly used for heating purposes. The development of new processes to produce high value-added lignin products such as multifunctional aromatic chemicals and high-tech carbon materials are required to fulfill the needs for biorenewable feedstocks. Such processes are likely to include selective oxidation catalysis.
The aim of this Thesis is to advance the state-of-the-art for the oxidation of lignin models and lignin extracts using homogeneous catalysts based on vanadium, an inexpensive and abundant transition metal, using air as the only oxidant. Lignin models containing the most important features of lignin (e.g., β-O-4 and β-1 linkages) were initially used to assess the catalytic potential. Previously reported (HQ)2V(O)(OiPr) and (dipic)V(O)(OiPr) catalysts (dipic = dipicolinate and HQ = 8-oxyquinoline) displayed different selectivity for C-H, C-O and C-C bond cleavage upon varying of the solvent, the lignin model or the catalyst. Moreover, these catalysts cleave the C-H bond of secondary alcohols through a two-electron oxidation process and the C-C bond cleavage of the oxidation product ketone in the presence of exogenous base.
Several amine bis(phenolate) oxovanadium(V) catalysts were synthesized and fully characterized, and demonstrated very good activity for the oxidation of lignin models and the depolymerization of organosolv lignin. These new catalysts overcome the need for added base, display higher reaction rates of oxidation, and improve the selectivity for the disassembly of lignin models. The different selectivities involving C-H vs. C-O vs. C-C bond cleavage are discussed together with a novel redox-neutral C-C bond cleavage of lignin model 1,2-diphenyl-2-methoxyethanol.
The oxovanadium(V) catalysts, along with a metal-free variant and other transition metal catalysts, were employed to assess their performance for the oxidation and depolymerization of organosolv lignin. Although most catalysts oxidized the lignin extracts, the oxovanadium(V) complexes demonstrated the highest degree of lignin depolymerization as shown by Gel Permeation Chromatography (GPC), quantitative-Heteronuclear Single Quantum Correlation (q-HSQC) and quantitative 31P NMR spectroscopy of derived phosphite esters.
In a complementary study, oxovanadium(V) catalysts also established their utility for the valorization of cellulose-derived substrates (e.g., diols). Two trialkoxyamine oxovanadium(V) complexes bearing a triethoxyamine and tris[2-(3,5-di-tert-butyl-phenoxy)methyl]amine ligand respectively, selectively cleaved the C-C bond in 1,2-diols with excellent rates and using air as the only oxidant. In a stoichiometric investigation of this reaction, it was determined that the transformation proceeds through an unusual direct oxidative two-electron cleavage of diols, affording a non-oxo monometallic V(III) intermediate. DFT calculations support a single-site proton-coupled electron-transfer of the hydroxyl hydrogen to the V oxo orbital.
In summary, this Thesis describes new developments in vanadium catalysis such as mechanistic implications and catalyst optimization for the valorization of lignocellulosic biomass utilizing air as an oxidant.
22
Bouchard, Francine T. "Novel thermally depolymerizable polycarbonates of tertiary, benzylic, or allylic diols." Thesis, University of Ottawa (Canada), 1986. http://hdl.handle.net/10393/4955.
23
Sagna, Joseph. "L'organisation socio-politique des diola (bayot et bandial) : étude diachronique." Paris 5, 1986. http://www.theses.fr/1986PA05H017.
Анотація:
Ce résumé est une synthèse de notre travail de recherche dont l'objet se rapporte à l'organisation socio-politique de la société diola en Casamance (Sénégal). Nous avons opté pour une étude diachronique, plutôt qu'une étude comparative de la société actuelle et de la société traditionnelle, afin de mettre en évidence le rapport dialectique qui existe entre société traditionnelle et colonisation dans la transformation des institutions et de la société diola. Notre thèse est donc divisée en deux périodes principales: - la première partie est essentiellement anthropologique et vise à recréer la société telle qu'elle a existé. Nous avons également étudié progressivement la famille traditionnelle et les institutions les unes après les autres, jusqu'à rendre ainsi compte de l'ancienne organisation avec sa logique constitutionnelle, ses acteurs et son système organisationnel. - la deuxième partie est consacrée à la période coloniale, qui elle- même comprend deux étapes historiques principales : la découverte du pays puis de la région de Casamance, et le début des échanges; et enfin, la seconde étape, la plus caractéristique qui concerne la colonisation et la pacification de la zone. Nous ne nous sommes pas arrêtés a cette période de la colonisation, mais nous avons tenté de poursuivre notre étude jusqu'après les indépendances, pour voir si ce nouvel avènement allait apporter, à son tour, de profondes modifications ou un rétablissement de l'ordre ancien. Bien entendu, nous ne voulons faire de cette présentation qu'un aperçu de notre thèse, et rappelons qu'elle ne peut en aucune manière remplacer l'argumentation et l'analyse de base développées dans notre recherche. Pour cela, nous invitons donc ceux qui s'intéressent à cette étude, de consulter notre thèse pour comprendre et saisir notre démarcheThe summary is a synthesis of our study whose topic is a social and political organization of Diola ethnic group (Bayot and Bandial) in Calamanco (Senegal). We chose to make a "diachronic" research rather than a comparative one between present and ancient society in order to enlighten the dialectic relation which exists between traditional society and colonization in the changes of Diola society and institutions. Our thesis is divided into two main periods: the pre-colonial period and the very period of colonization. So, the first part is mainly anthropological and tends to re-create Diola traditional society by analyzing symbols and thanks to those who have known it. Therefore, we have gradually studied traditional family and institutions, each by each, in order to give a precise idea of traditional society with its constitutional logic, its members and its organizational system. The second part deals with colonial period consisted of two major stages. The first stage relates to the discovery of Senegal, then of Casamance and to the beginning of exchanges. The second stage, more characteristic, concerns colonization and pacification of this area. We didn't bound our study to colonization but tried to analyze the period after independence to see whether this new advent would carry out deep changes or restore ancient order. As a matter of fact, we only want this summary to be a survey of our thesis and recall it can't, in any way, replace the argumentation and the basic analysis developed in our investigation. So, we invite those who are interested in our research work to cast a look at our thesis to understand our aim
24
Voith, Matthias. "Asymmetrische Synthese von 2 Methyl-substituierten 1,3-Diolen." Aachen : Shaker, 2003. http://deposit.d-nb.de/cgi-bin/dokserv?idn=969516622.
25
Bassene, Alain-Christian Creissels Denis. "Description du Joola Banjal (Sénégal)." Lyon : Université Lumière Lyon 2, 2006. http://theses.univ-lyon2.fr/sdx/theses/lyon2/2006/bassene_ac.
26
Ben, Chrait Imen. "Développement de réseaux polyuréthane à base d’oligocarbonates dihydroxytéléchéliques partiellement biosourcés." Thesis, Lille, 2018. http://www.theses.fr/2018LIL1R071.
Анотація:
Des oligocarbonates dihydroxytéléchéliques partiellement biosourcés ont été synthétisés par transcarbonatation en masse en faisant réagir l'isosorbide comme principal diol biosourcé et un diol aliphatique en tant que co-monomère avec du diphénylcarbonate en présence d'un catalyseur. Les oligomères ont été préparés en faisant varier le rapport des deux monomères diols. Les conditions de réaction ont été optimisées pour parvenir à une conversion totale en monomères tout en éliminant le phénol résiduel (sous-produit de la réaction). Les oligomères résultants portent des unités d'isosorbide à leurs deux extrémités de chaînes. La teneur en terminaisons hydroxyles a été déterminée par RMN-1H suivant une méthode de dérivatisation. Tous les oligocarbonates sont amorphes et leur Tg augmente avec l'augmentation de la teneur en isosorbide et avec la rigidité du co-monomère diol. Ces oligocarbonates ont été utilisés pour développer des revêtements polyuréthanne en ajoutant un polyisocyanate. Tous les revêtements obtenus sont transparents, brillants et présentent de très bonnes résistances aux solvants. Les propriétés thermiques, mécaniques et physico-chimiques des polyuréthanes dépendent à la fois de la structures de l’oligocarbonate et de celle du trimère d’isocyanatePartially bio-based dihydroxytelechelic oligocarbonates were synthesized by melt transcarbonatation polymerization using isosorbide as the principal bio-sourced diol and an aliphatic diol as co-monomer with diphenyl carbonate in the presence of a catalyst. The oligomers were prepared by varying the ratio of the two diol monomers. The reaction conditions were optimized to reach full conversion whilst also removing any residual phenol (by-product of the reaction). The resulting oligomers bear isosorbide units at both extremities. The hydroxyl group content is further determined by 1H-NMR according to a derivatization method. All the oligocarbonate diols were amorphous and their Tg increases with increasing isosorbide content and rigidity of the co-monomer diol. These oligocarbonates were used to develop polyurethane coatings by adding a polyisocyanate. All the coatings obtained are transparent, glossy and have a very good solvents resistance. The thermal, mechanical and physicochemical properties of polyurethanes depend on the structures of the oligocarbonate and the polyisocyanate used
27
Estupiñán, Romero Mónica. "Comprehensive analysis of Pseudomonas aeruginosa oleate-diol synthase activity." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/360336.
Анотація:
The discovery of new biotechnological applications of hydroxy fatty acids such as the oxylipins, has provided the basisto explore new mechanisms of oxylipin biosynthesis in prokaryotes, as no evidence on the occurrence of oxylipin production in bacteria existed for a long time. In 2010, a diol synthase activity was biochemically characterized in Pseudomonas aeruginosa 42A2, an environmental strain isolated from oily-waste water, which enables accumulation oxylipins in the extracellular medium. This rare diol synthase activity has been described for the first time in bacteria, generating oxylipins with interesting properties by oxygenation of monounsaturated fatty acids, preferentially oleic acid. The catalytic mechanism proceeds through the dioxygenation of oleic acid to release (10S)-hydroperoxy-(8E)- octadecenoic acid (10S-HPOME), which is reduced to (10S)-hydroxy-(8E)- octadecenoic acid (10S-HOME) through a secondary non-enzymatic reaction, followed by conversion of the hydroperoxide intermediate into (75,10S)-dihydroxy¬(8E)-octadecenoic acid (7,10-DiHOME).However, the genes involved in oxylipin biosynthesis and transport to the extracellular medium, and the biological relevance of these metabolites in this bacterium remained unknown. The current work reports the first outer membrane transporter of oxylipins in P. aeruginosa, the ExFadLO, and identifies the operon structure of the genes coding for two previously uncharacterized enzymes involved in oleate-diol synthase activity, acting sequentially as oleic acid dioxygenase (10S-DOX) and hydroperoxide isomerase or diol synthase (7,10-DS) activities. These proteins belong to a new subfamily of bacterial enzymes, designated as FadCCPs, only found among P. aeruginosa species. Insights into this unique oleate-diol synthase metabolic route evolutionary pathway, and the possible biological relevance of oxylipin biosynthesis and metabolism in P. aeruginosa are discussed. Moreover, a biotechnological approach to P. aeruginosa oleate-diol synthase activity for oxylipin production is proposed.Estudio global de la actividad oleato diol sintasa en Pseudomonas aeruginosa El descubrimiento de nuevas aplicaciones biotecnológicas de ácidos grasos hidroxilados tales como las oxilipinas, ha proporcionado las bases para explorar nuevos mecanismos de biosíntesis de oxilipinas en procariotas, ya que durante mucho tiempo no hubo evidencias sobre la producción de oxilipinas en bacterias. En 2010, se caracterizó bioquímicamente la actividad diolsintasa en Pseudomonas aeruginosa 42A2, una cepa del medio ambiente aisladaen aguas contaminadas con residuos oleaginosos, capaz de acumular oxilipinas en el medio extracelular. Esta actividad diol sintasa ha sido descrita por primera vez en bacterias, posibilitando la obtención de oxilipinas con propiedades interesantes mediante la oxigenación de ácidos grasos monoinsaturados, preferentemente el ácido oleico. El mecanismo catalítico descrito tiene lugar a través de la dioxigenación de ácido oleico para liberar ácido (105)-hidroperoxi-(8E)-octadecenoico (105-HPOME), que se reduce al ácido (105)-hidroxi-(8E)-octadecenoico (105-HOME) a través de una reacción secundaria no enzimática, seguido por la conversión del intermediario hidroperóxido a ácido (75,105)-dihidroxi-(8E)-octadecenoico (7,10-DiHOME). Sin embargo, los genes implicados en la biosíntesis de oxilipinas y su transporte al medio extracelular, así como la relevancia biológica de estos metabolitos en esta bacteria eran desconocidos. El presente trabajo describe el primer transportador de membrana externa de oxilipinas en P. aeruginosa, la proteína ExFadLO, e identifica el operón cuyos genes codifican dos enzimas no caracterizadas hasta el momento, que participan en la actividad oleato diol sintasa actuando de forma secuencial mediante las actividades dioxigenasa del ácido oleico (105-DOX) e hidroperóxido isomerasa o diol sintasa (7,10-DS). Estas proteínas pertenecen a una nueva subfamilia de enzimas bacterianas, designadas como FadCCPs, distribuidas únicamente entre las especies de P. aeruginosa. Además, se discuten nuevos aspectos en torno a la vía evolutiva de la ruta metabólica oleato diol sintasa,y la posible relevancia biológica de la biosíntesis de oxilipinas y su metabolismo en P. aeruginosa. Por último, se propone una aproximación biotecnológica de la actividad oleato diol sintasa de P. aeruginosa para la producción de oxilipinas.
L'activitat oleat diol sintasa va ser caracteritzada bioquímicament en Pseudomonas aeruginosa 42A2, una soque del medi ambient aïllat en aigües contaminades amb residus oleaginosos, capaç d'acumular oxilipines derivades de l'àcid oleic com els àcids (10S)-hidroperoxi-(8E)-octadecenoic (10S-HPOME), (10S)-hidroxi-(8E)- octadecenoic (10S-HOME) i (7S,10S)-dihidroxi-(8E)-octadecenoic (7,10-DiHOME) en el mediextracel·lular. Aquest treball descriu el primer transportador de membrana externa de oxilipines en P. aeruginosa, la proteïna ExFadLO, i identifica l'operó del qual gens codifiquen dos enzims no caracteritzades fins al moment, que participen en l'activitat oleat diol sintasa, actuant de forma seqüencial mitjançant les activitats dioxigenasa de l'àcid oleic (10S-DOX) i hidroperòxid isomerasa o diol sintasa (7,10-DS). Aquestes proteïnes pertanyen a una nova subfamília d'enzims bacterians, designades com FadCCPs, distribuïdes únicament entre les espècies de P. aeruginosa. A més, es discuteixen nous aspectes al voltant de la via evolutiva de la ruta metabòlica oleat diol sintasa i la possible rellevància biològica de la biosíntesi de oxilipinas i el seu metabolisme en P. aeruginosa. Finalment, es proposa una aproximació biotecnològica de l'activitat oleat diol sintasa de P. aeruginosa per a la producció de oxilipines.
28
Gujral, Chirag Harsharan Singh. "Boronic-diol complexation as click reaction for bioconjugation purposes." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/boronicdiol-complexation-as-click-reaction-for-bioconjugation-purposes(a7072d58-2a4f-4d0f-bcab-6cd709bdac12).html.
Анотація:
The research presented in this thesis focuses on the study of the reaction between boronic acids and diols and its evaluation as a possible "click" reaction, possibly applicable in bioconjugation and drug delivery. A key feature of this reaction is its reversibility at acidic pH, which could allow the release of a diol-containing drug from a bioconjugate in the acidic environment of late endosome/lysosome, possibly after undergoing receptor mediated endocytosis. Over the last two decades various studies have focused on the study of the conjugation of boronic acids to diols using Alizarin Red S as a fluorescence reporter. In this research we have presented an alternative method based on the batochromic shifts of Alizarin Red S absorbance; this method is particularly advantageous in complex systems with an elevated scattering, such as colloidal dispersions or for binding to complexed active compounds. We have therefore demonstrated that this method allows the determination of equilibrium constants between diols (e.g. catecholamines) and boronic acids. We have also demonstrated that the method allows to follow the kinetics of enzymatic reactions involving catechols; in particular, we have focused on cytochrome P450-mediated reactions such as the conversion of estradiol to 2-hydroxyestradiol using CYP1A2, or the demethylation of 3-methoxytyramine to dopamine using CYP2D6. Once we have established a reliable method for following this reaction on low molecular weight compounds, we have applied it to polymeric bioconjugates. Specifically, we have selected hyaluronic acid (HA) as a biocompatible and biodegradable polymeric backbone and produced derivatives containing boronic acids, catechols and dimethylated catechols (as negative controls). The resulting polymers where characterised via UV-Vis, 1H NMR and SLS, also qualitatively evaluating their cytotoxicity and enzymatic degradability. The conjugates with boronic acids showed the lowest cytotoxicity, and the highest degradability. The complexation of HA-boronic derivatives was then studied; using the same library of diols previously used with low molecular weight compounds, evaluating the effect of the presence of the polysaccharidic macromolecular chain.
29
Charron, Martin. "Novel naphthalene-2,3-diol antioxidants: Design, synthesis and reactivity." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26866.
Анотація:
Antioxidants, which are molecules capable of inhibiting or quenching free radicals, are believed to be very important molecules for preventing and limiting ''oxidative stress'' in human cells. This oxidative stress is caused by unwanted reactions between free radicals and cell's vital constituents, such as DNA, proteins and lipids. These reactions are responsible for lipid peroxidation, DNA and proteins breakage and mutations that are today known to be associated with degenerative diseases such as Parkinson's and Alzheimer's disease as well as with aging. The design and development of new antioxidant molecules more effective than Vitamin E, a key antioxidant in human blood, may have value in the prevention of some diseases and slow down the aging process.
Compounds 23 and 66, for example, were 2 and 84 times more effective than Vitamin E at quenching DPPH. These compounds were also shown to be considerably less toxic to Adrenal Pheochromocytoma cells than the catechols such as 3 and 6.*
*Please refer to dissertation for diagrams.
30
Fournier, Rémi. "Polymères associatifs par interaction covalente réversible diol-acide boronique." Thesis, Paris 6, 2016. http://www.theses.fr/2016PA066401/document.
Анотація:
Ce travail de thèse porte sur la synthèse et l'étude physico-chimique de polymères associatifs hydrosolubles à associations complémentaires. Utilisant la chimie covalente réversible, ce système met en jeu l'association d'un poly(diol) et d'un poly(acrylamide) partiellement hydrolysé portant des fonctions d'acide boronique. Ces dernières sont introduites par une technique de greffage qui a été optimisée et finement caractérisée. Le mélange des deux polymères permet d'obtenir des solutions visqueuses et des gels dynamiques et ceci pour de faibles concentrations. La possibilité de viscosifier des formulations en-dessous de la concentration de gélification constitue un résultat marquant qui distingue ce système de nombreux polymères à association hydrophobe. Dans le régime de gel, les propriétés rhéologiques linéaires sont analysées en relation avec l'étude de la force des interactions moléculaires qui ont été mesurées par la RMN du bore et une technique de fluorescence. La rhéologie non-linéaire apporte des informations essentielles sur la relation entre le cisaillement et la structure du réseau réversible formé. L'utilisation d'un système de visualisation de l'échantillon sous écoulement permet l'observation d'effets locaux fortement non-linéaires. L'influence des différents paramètres, comme le pH et la température, sur les propriétés dynamiques des solutions peut être rationalisée et modélisée en termes de lois d'échelles. L'originalité de ce concept de système associatif par associations complémentaires est mise en perspective au travers d'une revue de la littérature rationalisant le lien entre architecture et rhéologie des polymères associatifs hydrosolublesThis thesis deals with the synthesis and the physical chemistry study of water-soluble complementary associative polymers. Based on reversible covalent chemistry, this system brings into play the association of a poly(diol) and of a partially hydrolyzed poly(acrylamide) bearing boronic acid moieties. The latter are introduced by a grafting technique which has been optimized and finely characterized. The mixing of these two polymers allows obtaining viscous solutions and visco-elastic gels at relatively low polymer concentrations. The possibility to make formulations viscous below the gel point represents a remarkable result, which differentiates this system to numerous associative polymers based on hydrophobic interactions. In the gel regime, the linear rheological properties are analyzed with regard to the strength of molecular interactions which have been measured by boron NMR and a fluorescence technique. Non-linear rheology brings essential information about the relationship between shearing and the structure of the formed reversible network. The use of a visualization setup of samples under flow enables the observation of very non-linear local effects such as wall slip and shear-banding. The influence of various parameters, as pH and temperature, on the dynamical properties of solutions and gels can be rationalized and modeled in terms of scaling laws. The originality of this concept of associative system with complementary associations is put into perspective through a literature review on the relationship between architecture and molecular interactions on one hand, and rheological properties of associative polymers on the other hand
31
BARBIERI, PATRICK. "Nouvelles syntheses d'heterocycles utilisant le dioxanne-1,4 diol-2,3." Paris 6, 1989. http://www.theses.fr/1989PA066737.
Анотація:
Nouvelles syntheses d'heterocycles utilisant le dioxanne-1,4 diol-2,3. Le glyoxal ou ethanedial, le plus simple des dialdehydes alphatiques est un synthon tres utile tant en chimie heterocyclique, qu'en chimie macromoleculaire. Son utilisation a l'etat pur est difficile car il se polymerise rapidement. L'emploi de la combinaison bisulfitique ou des solutions aqueuses de ce reactif entraine parfois des problemes de reactivite et d'isolement des produits. Le dioxanne-1,4- diol-2,3, issu de la combinaison du glyoxal avec l'ethyleneglycol est un compose cristallise stable a temperature ambiante et regenere facilement le dialdehyde dans des conditions douces. Nous avons mis a profit les proprietes interessantes de ce derive du glyoxal pour preparer l'imidazole et la pyrazinone ainsi que certains de leurs derives respectifs
32
Awenengo, Dalberto Séverine. "Les Joola, la Casamance et l'État (1890-2004) : l'identisation Joola au sénégal." Paris 7, 2005. http://www.theses.fr/2005PA070036.
Анотація:
ENTRE LA FIN DU 19e SIECLE ET LE DEBUT DES ANNEES 2000, LES POPULATIONS DE LA BASSE-CASAMANCE SE SONT PROGRESSIVEMENT CONSTITUEES ET IMAGINEES EN COMMUNAUTE JOOLA. CE TRAVAIL ANALYSE LES PROCESSUS DE CETTE " IDENTISATION ", OU CONSTRUCTION IDENTITAIRE, QUI SE SONT ENGAGES ET RENFORCES AVEC LA CREATION, LA GESTION, L'IMAGINATION ET LES USAGES, DANS L'ORDRE COLONIAL PUIS INDEPENDANT, DE LA CASAMANCE ET DU SENEGAL EN D'AUTRES TERMES, IL ETUDIE LA FONCTION DE LA REPRESENTATION JOOLA EN EXAMINANT LA FAÇON DONT LES POPULATIONS DE LA BASSE-CASAMANCE, LA CASAMANCE, LE SENEGAL ET L'ETAT SE SONT MUTUELLEMENT PRATIQUES ET IMAGINES, FAVORISANT LA COMPOSITION D'UNE COMMUNAUTE JOOLA DONT L'IDENTITE NE S'EST STANDARDISEE QUE TRES RECEMMENT, SOUS L'EFFET DES TRAVAUX CULTURELS ET DES INVENTIONS DE LA TRADITION QUI SE SONT MULTIPLIES AVEC LE DECLENCHEMENT DU MOUVEMENT INDEPENDANTISTE CASAMANCAIS EN 1982. L'ETUDE DES CONSTRUCTIONS - ET DE LEURS ARTICULATIONS - DES IDENTITES JOOLA, CASAMANCAISE, SENEGALAISE ET CITOYENNE, EN PRIVILEGIANT UNE APPROCHE MULTIVOQUE DE L'IDENTITE JOOLA, MONTRE QUE C'EST DANS LA RUPTURE DE LA LIAISON CITOYENNE ET NON DANS LA FORMATION D'UNE IDENTITE JOOLA ET CASAMANCAISE QUE DOIT SE COMPRENDRE LA CRISE CASAMANCAISE CE TRAVAIL PERMET AUSSI D'ETUDIER AUTREMENT, A PARTIR DE LA PERIPHERIE JOOLA ET CASAMANCAISE, LE SENEGAL COLONIAL ET INDEPENDANT, LEURS MODELES, HERITAGES ET MODES DE TRANSMISSION. FONDEE SUR DES SOURCES D'ARCHIVES DE LA FRANCE COLONIALE ET SUR DES TEMOIGNAGES ORAUX, CETTE THESE A EGALEMENT ETE BASEE SUR DES ARCHIVES PRIVEES INEDITES ET INACCESSIBLES, QUE LE VOLUME D'ANNEXES PERMET DE CONSULTER EN PARTIEBetween the end of the 19th century and the beginning of the years 2000, the populations of lower casamance have gradually constituted and imagined themselves as a community and as a joola community. This work analyses the processes of this "identisation" - or identity building - which have emerged and seen themselves reinforced through the creation, the management, the imagination and the uses of casamance and senegal at first in the colonial order, then in the independent state. In other words, it examines the function of joola identity by going into the way the populations of lower casamance, casamance, senegal and the state were mutually practiced and imagined. This has promoted the composition of a community joola whose identity was standardized only very recently, under the effect of cultural works and inventions of tradition which has seen themselves multiplied with the start of the separatist movement of casamance in 1982. The study of the constructions - and theirs articulations - of the joola, casamancaise, senegalese and citizen identites, privileging various approaches of joola identity, shows that it is in the rupture of the citizenship connection and not in the formation of a joola or casamancaise identity that the casamance crisis must be understood. This work also allows to study differently, starting from the casamance and joola periphery, the colonial and the independent senegal, their models, heritages and modes of transmission. Based on sources of files of colonial and on oral testimonies, this thesis was also based on new and inaccessible private archives, that the volume of appendices makes it possible to consult partly
33
Coen, Gerard Patrick. "Enzyme-catalysed synthesis and applications of enantiopure alkene and arene diols." Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343093.
34
Smith, Martin A. "The monofunctionalisation of 1,n diols catalysed by lanthanide (III) salts." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431327.
35
Suthers, William G. "Regioselective copper (II) mediated protection of trans diols in D glucopyranosides." Thesis, University of Reading, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252231.
36
Smith, Zoe Ann. "A pinacol coupling approach towards the synthesis of 3,4-pyrrolidine-diols." Thesis, University of Leicester, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409371.
37
Leijondahl, Karin. "Synthesis and asymmetric transformations of diols by enzyme- and ruthenium catalysis /." Stockholm : Department of Organic Chemistry, Stockholm university, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-8294.
38
Grossart, Allan G. "A study of some liquid crystalline materials containing 1, 2-diols." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.627608.
39
Betou, Marie. "Semipinacol rearrangement of cis-fused β-lactam diols into bicyclic lactams". Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/4348/.
Анотація:
The 6-azabicyclo[3.2.1]octane ring system is found in a wide variety of biologically active natural and non-natural products. The aim of this project is to prepare the 7,8-diketo-6-azabicyclo[3.2.1]octane structure via a semipinacol rearrangement of ring-fused β -lactams. Chapter 1 introduces the pinacol and semipinacol rearrangement, including the use of cyclic sulfites and phosphoranes, and ring expansion of β -lactams. Previous work in the Grainger group for the synthesis of lactams via tandem radical cyclisation-dithiocarbamate group transfer is also discussed. Chapter 2 describes the methodology developed for the semipinacol rearrangement of β-lactams. Access to suitable precursors for the semipinacol rearrangement is achieved through a sequence of 4-exo trig radical cyclisation, base-mediated dithiocarbamate group elimination and dihydroxylation. Formation of the 7,8-diketo-6-azabicyclo[3.2.1]octane ring system occurs through semipinacol rearrangement of the corresponding cyclic sulfites and phosphoranes. In Chapter 3, the scope and limitations of the methodology are explored. Different substituents on the nitrogen of the β-lactam, groups on the cyclohexane moiety (methyl and oxygenation) and ring sizes are investigated. An original approach to the total synthesis of peduncularine is described in Chapter 4. Synthesis of a suitably functionalised β-lactam and attempts to further transform it into the desired 7,8-diketo-6- azabicyclo[3.2.1]oct-3-ene structure are reported. Work towards the total synthesis of calyciphylline D, calyciphylline F and caldaphnidine M is described in chapter 5. Reductive amination and stereoselective reduction of piperitone are investigated. Use of a model system for the addition of nucleophiles onto thiolactams is also described.
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Angell, Valerie. "Monoalkylation of 1,2-diols and Design of First Aid Smart Fabrics." Thesis, Boston College, 2012. http://hdl.handle.net/2345/3854.
Анотація:
Thesis advisor: Marc SnapperMonoalkylation of 1,2diols: No method for an asymmetric monoalkylation has been previously reported. Attempts here were made to develop this transformation by using a copper catalyst and BOX ligand to impart chirality. Design of First Aid Smart Fabrics: A cellulose filter paper would be linked through a cleavable linker to a bioactive agent. This linker would cleave upon the presence of blood to release the drug directly onto the body
Thesis (MS) — Boston College, 2012
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Pushina, Mariia. "Sensing of Anions, Amines, Diols, and Saccharides by Supramolecular Fluorescent Sensors." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1558539245401457.
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Huang, Kuan-Chen. "Study The Application of Non-isocyanate Approach in Polyurethanes and Diols." University of Akron / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=akron161729301625948.
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Nieman, James A. "Improved syntheses and resolutions of cis, cis-spiro(4.4) nonane-1,6-diol and cis, cis-2,2'-spirobiindane-1,1'-diol, applications as chiral auxiliaries." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/nq20760.pdf.
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McKibben, Bryan P. "Reactivity studies of arene-cis-diols in cycloadditions and potassium permanganate oxidations : synthesis of the corresponding arene-trans-diols and an approach to the synthesis of (+)-pancratistatin /." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-164317/.
45
Rabenstein, Michael. "Untersuchungen zur Zyklisierung bei Polykondensationsreaktionen." [S.l. : s.n.], 2001. http://www.sub.uni-hamburg.de/disse/361/Disse.pdf.
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Bassene, Alain-Christian. "Description du Joola Banjal (Sénégal)." Lyon 2, 2006. http://theses.univ-lyon2.fr/documents/lyon2/2006/bassene_ac.
Анотація:
Cette thèse présente une description générale et aussi complète que possible de la grammaire du jóola banjal, langue atlantique parlée par environ 7. 000 locuteurs en Casamance, au sud-ouest du Sénégal. Cette description passe en revue la phonologie, la morphophonologie, la morphologie et la syntaxe, d’un point de vue typologique et fonctionnel. Le jóola banjal compte deux types de voyelles selon le trait ±ATR et une structure syllabique de forme (C)V(C(C)). C’est une langue à classes nominales dans laquelle adjectifs, pronoms, démonstratifs, interrogatifs et verbes sont soumis à l’accord en classe imposé par le substantif. Cet accord se manifeste par la répétition du préfixe de classe devant chaque élément en relation syntaxique avec ce dernier. La présence de l’indice de sujet est généralement obligatoire, même en présence d’un constituant sujet. La partie syntaxique est organisée selon les rubriques suivantes : la prédication non verbale, les modifications de la valence verbale, l’expression de la localisation et du déplacement, les formes verbales non finies, la phrase complexe, la topicalisation, la focalisation et l’interrogation. D’une manière générale, le jóola banjal ne présente pas de particularités typologiques exceptionnelles par rapport aux langues les plus connues du groupe atlantique. Néanmoins, son étude offre des informations utiles pour une meilleure connaissance des langues atlantiques et pour leur étude comparativeThis dissertation presents a general description, as complete as possible, of Jóola Banjal, an Atlantic language spoken by almost 7,000 speakers in Casamance, in the South-west of Senegal. This description consists of a study of phonology, morphophonology, morphology, and syntax, in a typological and functional approach. Jóola Banjal has two types of vowels according to ±ATR feature and a syllabic structure of form (C)V(C(C)). It is a noun class language in which adjectives, pronouns, demonstratives, interrogatives and verbs agree in class with nouns. This agreement is marked by the prefixation of a class marker to every element in syntactic relation with the noun. The presence of the subject marker is generally obligatory, even when the subject noun is present. The syntactic part of the description is organized along the following topics: non verbal predication, changing valency, encoding location and motion, non-finite verb forms, complex constructions, topicalization, focalization, and interrogation. Generally speaking, Jóola Banjal does not present exceptional typological characteristics with regard to the best-known Atlantic languages. Nevertheless, its study provides information useful for a better knowledge of the Atlantic languages and for comparative studies
47
Beluocine, T. "Chemoenzymatic synthesis of enantiopure arene cis-diols : applications in asymmetric homogenous catalysis." Thesis, Queen's University Belfast, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.431407.
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Silwood, Christopher James Leslie. "NMR spectroscopic studies of intramolecular hydrogen bonding in 1,2-and 1,3-DIOLS." Thesis, Birkbeck (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404485.
49
Pitzer, Kevin K. "The synthesis of amino- and deutero- sugars from halo-cyclohexadiene-cis-diols." Diss., This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-06062008-155317/.
50
Merad, Jérémy. "Synthèse énantiosélective organocatalysée de 1,3-diols acycliques par amplification de type Horeau." Thesis, Aix-Marseille, 2015. http://www.theses.fr/2015AIXM4357.
Анотація:
Les 1,3-diols acycliques sont des motifs ubiquitaires, essentiels dans la structure de nombreux produits naturels. Le développement d’approches permettant leur obtention de manière énantiosélective se révèle donc d’un grand intérêt synthétique. Dans ce contexte, notre équipe a envisagé une stratégie reposant sur des transferts d’acyle énantiosélectifs organocatalysés multiples. Cette approche a abouti à la mise en oeuvre d’une méthodologie de désymétrisation énantiosélective organocatalysée de 1,3-diols méso acycliques. Les composés ainsi obtenus constituent des briques moléculaires aisément valorisables en synthèse totale. Une approche similaire a permis de décrire, dans un second temps, une méthode inédite de double dédoublement cinétique de 1,3-diols anti. Générale et pratique, ce procédé fournit des diols énantiopurs de structures variées. La particularité de ces méthodologies réside dans l’exploitation du principe de Horeau se traduisant par une amplification de l’énantiosélectivité déployée par le catalyseur chiral. Les isothiourées employés dans ces réactions constituent une famille de bases de Lewis azotées dont la capacité à promouvoir les réactions d’acylation énantiosélectives n’a été découverte que récemment. Bien que leur utilisation en catalyse énantiosélective se soit rapidement démocratisée, les éléments structuraux responsables de leur sélectivité n’ont pas été totalement identifiés. Avec le nouvel objectif d’établir une relation entre structure, réactivité et sélectivité de ces molécules, des isothiourées originales ont été synthétisées et leur potentiel catalytique étudié en détailAcyclic 1,3-diols are ubiquitous scaffolds, essential in the structure of numerous natural products. The developpment of innovative pathways allowing their enantioselective obtention is of first interst in organic synthesis. In this context, our team envisaged a strategy of multiple organocatalyzed enantioselective acyl transfers. This approach led to the implement of a methodology based on the organocatalyzed desymmetrization of meso 1,3-diols. The desymmetrized compounds were obtained with high level of enantioselectivity and were used as useful building blocks easily valorizable in total synthesis. In a second time, we developed an organocatalyzed method of double kinetic resolution (DoCKR) of anti 1,3-diols. Very general, practicable and useful, this process allows the preparation of enantiopur diols with a large structural diversity. The particularity of these methods reside in the exploitation of the Horeau principle leading to the amplification of the enantioselectivity. These phenomons of kinetic amplification, often anecdotic, were used in this study as a powerful tool.The employed isothioureas belong to the nitrogenated Lewis bases family which were discovered only very recently to promote enantioselective acyl transfer. Although their uses in enantioselective catalysis were rapidly democratized, the structural feature responsible of their selectivity are not all clearly identified. To establish a relationship between structure, reactivity and selectivity of theses molecules, new isothioureas were synthesized and evaluated in enantioselective catalysis