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1
Hamilton, Caroline. "Investigations of macrocyclic esters and ether-esters". Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298341.
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Said, M. S. "Hydrolysis mechanisms for iminosulphonate esters and fluorene esters". Thesis, University of Essex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.353160.
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Nagatomi, Eiji. "Autoxidation of neopentyl esters used as models for synthetic ester lubricants". Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.482785.
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Arca, Hale Cigdem. "Cellulose Esters and Cellulose Ether Esters for Oral Drug Delivery Systems". Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/82920.
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Amorphous solid dispersion (ASD) is a popular method to increase drug solubility and consequently poor drug bioavailability. Cellulose ω-carboxyesters were designed and synthesized specifically for ASD preparations in Edgar lab that can meet the ASD expectations such as high Tg, recrystallization prevention and pH-triggered release due to the free -COOH groups. Rifampicin (Rif), Ritonavir (Rit), Efavirenz (Efa), Etravirine (Etra) and Quercetin (Que) cellulose ester ASDs were investigated in order to increase drug solubility, prevent release at low pH and controlled release of the drug at small intestine pH that can improve drug bioavailability, decrease needed drug content and medication price to make it affordable in third world countries, and extent pill efficiency period to improve patient quality of life and adherence to the treatment schedule. The studies were compared with cellulose based commercial polymers to prove the impact of the investigation and potential for the application. Furthermore, the in vitro results obtained were further supported by in vivo studies to prove the significant increase in bioavailability and show the extended release.
The need of new cellulose derivatives for ASD applications extended the research area, the design and synthesis of a new class of polymers, alkyl cellulose ω-carboxyesters for ASD formulations investigated and the efficiency of the polymers were summarized to show that they have the anticipated properties. The polymers were synthesized by the reaction of commercial cellulose alkyl ethers with benzyl ester protected, monofunctional hydrocarbon chain acid chlorides, followed by removal of protecting group using palladium hydroxide catalyzed hydrogenolysis to form the alkyl cellulose wcarboxyalkanoate. Having been tested for ASD preparation, it was proven that the polymers were efficient in maintaining the drug in amorphous solid state, release the drug at neutral pH and prevent the recrystallization for hours, as predicted.Ph. D.
5
Deshpande, S. D. "Borate esters promoted epoxidation". Thesis(M.Sc.), CSIR-National Chemical Laboratory, Pune, 1989. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2284.
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Witt, Fiona Joy. "Synthetic approaches towards phorbol esters". Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276852.
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Belogi, Gianluca. "Boronate esters in oligosaccharide synthesis". Thesis, University of Birmingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367628.
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Marriott, Robert Edward. "Accelerated cleavage of phosphate esters". Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272476.
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Zheng, Xueyan. "Regioselective Synthesis of Cellulose Esters". Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/49540.
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Cellulose is an extraordinarily abundant polymer that can be harvested and purified from trees and other renewable sources. Cellulose derivatives have been widely used as coatings, optical films, fibers, molded objects, and matrices for controlled release. The properties of cellulose derivatives are not only affected by the degree of substitution, but also by the position of substitution. In order to establish the structure-property relationships of cellulose derivatives, it is of great importance to impart regioselectivity into functionalized cellulose. However, regioselective substitution of cellulose is extremely challenging, especially in the synthesis of regioselectively functionalized cellulose esters due to the unstable ester bond under aqueous alkaline or acid conditions.
In this dissertation, the main objective is to search for new tools to synthesize regioselectively substituted cellulose esters, to understand how structural changes impact properties and performance, and thus to design cellulose derivatives delivering high performance. Several strategies for regioselective preparation of cellulose esters are discussed in detail. The obtained regioselective cellulose esters were fully characterized analytically.Ph. D.
10
Gao, Chengzhe. "Regioselective chlorination of cellulose esters". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/96548.
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Chemical modification of cellulose has been of growing interest, owing to the abundance and processing challenges of natural cellulose. To date, etherification and esterification are the most effective strategies to modify physicochemical properties of cellulose and append new functionalities. However, they typically require relatively harsh conditions, thus limiting introduction of new functional groups. An alternative strategy to synthesize novel cellulose derivatives is to append a good leaving group to cellulose backbone, followed by nucleophilic substitution reaction. Though tosylation and bromination of cellulose are frequently used, they have drawbacks such as chemo- and regioselectivity issues, high cost, and difficulty in purification. We have successfully developed a method to chemo- and regioselectively chlorinate cellulose esters using MsCl. Compared to bromination of cellulose typically used, this chlorination method has many advantages, including low cost of reagents and ease of separation. The chlorinated cellulose esters are useful intermediates for appending new functionalities by displacement reactions. We have synthesized a library of cellulose ester derivatives by this chlorination/nucleophilic substitution strategy, including cationic and anionic cellulose ester derivatives. These cellulose ester derivatives possess great potentialiii for various applications, including amorphous solid dispersion, tight junction opening, anionic drug delivery, and gas separation membranes.MS
11
Steele, Heather L. "Permeation Sampling of Phthalate Esters". University of Akron / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=akron1242748589.
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Balaguer, Amanda Marie. "Routes to Acylated Sydnone Esters". Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1316529382.
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Schaff, Jilla. "Fluorinated esters : synthesis and identification". PDXScholar, 1988. https://pdxscholar.library.pdx.edu/open_access_etds/3921.
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Reactions of different alcohols with 2-hydroxy - 1- trifluoromethyl -1,2,2-trifluoroethanesulfonic acid sultone were studied. Six new esters were prepared: C6F5OC(O)CF(CF3)SO2F, CH3CH2OC(O)CF(CF3)SO2F, CF3CH2OC(O)CF(CF3)SO2F, (CF3)2CHOC(O)CF(CF3)SO2F, CH2=CHCH20C(O)CF(CF3)SO2F, (CH2OC(O)CF(CF3)SO2F)2. Analytical data, infrared, nmr and mass spectra are presented supporting the proposed structures for these new compounds.
14
Giner, Gil Marta. "Role of allyl esters in pest control". Doctoral thesis, Universitat de Lleida, 2012. http://hdl.handle.net/10803/94147.
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Les propietats insecticides d’una sèrie d’esters d’al•lil va ésser avaluada en diferents insectes mitjançant diferents modes d’aplicació. L’acció per aplicació tòpica va variar en funció de l’ester d’al•lil aplicat. El cinamat i el naftoat d’al•lil van ser els compostos més actius front a ous i larves neonates de C. pomonella, G. molesta i L. botrana, mentre que el salicilat d’al•lil no va produir mortalitat a la major dosi assajada (10 mg/mL). El cinamat d’al•lil va ser l’únic ester actiu per aplicació tòpica en adults de A. pisum, mentre que tots els esters d’al•lil testatsvan ser actius en adults de T. castaneum.
Els esters d’al•lil assajats van produir una pèrdua de la viabilitat cel•lular en les línees cel•lulars d’insectes quan va èsser mesurda mitjançant dos metodologies diferents (MTT i Blau de tripà), degut a una disrupció de les membranes cel•lulars. El cinamat d’al•lil va ser el compost més actiu i les cèl•lules procedents de l’aparell digestiu de Choristoneura fumiferana (Lepidòpter) les més sensibles. L’acció insecticida per ingestió va ser confirmada en larves de S. littoralis i C. pomonella, i en nimfes de A. pisum, senyalant l’aparell digestiu com a principal punt d’acció dels esters d’al•lil.
Els corresponents àcids i dicloropropilesters van mostrar una menor o igual acció insecticida que els corresponents esters d’al•lil, deguda també, a una acció en la membrana cel•lular. Les diferències en l’acció dels compostos seria deguda a diferències en les propietats lipofíliques dels compostos i la seva interacció amb les membranes cel•lulars.
Pel que fa a l’efecte dels esters d’al•lil en la comunicació química dels insectes, aquesta va tenir lloc en T. castaneum però no en A. pisum, el que es podria utilitzar per a mantenir els productes enmagatzemats lliures de T. castaneum. Pel que fa a C. pomonella i a L. botrana, tots els esters d’al•lil assajats van produir una resposta en les antenes dels mascles de C. pomonella, però tan sols el cinamat d’al•lil la va provocar en les femelles de C. pomonella i en mascles i femelles de L. botrana. Aquesta acció no es va veure reflexada en un increment de l’atracció de mascles cap a fonts amb l’ester d’al•lil i feromona en assajos en túnel de vent, però si en l’atracció de femelles. Aquest fet podria utilitzar-se per a incrementar el nombre de captures de femelles en trampes de feromona.
Aquests resultats suggereixen un paper dels esters d’al•lil en el control de plagues, especialment del cinamat d’al•lil.La acción insecticida de varios esteres de alilo fue testada en diversos insectos y mediante distintos modos de aplicación. La actividad por aplicación tópica varió en función del éster de alilo. El cinamato de alilo y el naftoato de alilo fueros los compuestos más activos en huevos y larvas neonatas de C. pomonella, G. molesta y L. botrana, mientras que el salicilato de alilo no produjo mortalidad a la dosis más alta testada (10 mg/mL). El cinamato de alilo fue el único éster activo por aplicación tópica en A. pisum mientras que todos los esteres testados lo fueron para T. castaneum. Los esteres de alilo estudiados produjeron pérdida de viabilidad celular en todas las líneas celulares de insectos cuando dicha viabilidad fue analizada mediante dos metodologías distintas (MTT y Azul de Tripano), y siendo ésta debida a la disrupción de la membrana celular. El cinamato de alilo fue el producto más activo, y las células del aparato digestivo de Choristoneura fumiferana (Lepidoptera) las más sensibles. La acción insecticida por ingestión en larvas de S. littoralis y C. pomonella, y en ninfas de A. pisum, fue confirmada y el aparato digestivo fue señalado como principal punto de acción de los esteres de alilo. Los correspondientes ácidos y dicloropropilesteres presentaron una menor o igual acción insecticida que los esteres de alilo siendo dicha acción también debida a un efecto en la membrana celular. Las diferencias en la acción de los distintos compuestos podrían ser debidas a diferencias en las propiedades lipofílicas de los compuestos y su interacción con las membranas celulares. Los esteres de alilo produjeron un efecto en la comunicación química de T. castaneum pero no en A. pisum, lo que podría utilizarse para mantener los productos almacenados libres de T. castaneum. En cuanto a C. pomonella y L. botrana, todos los esteres de alilo probados produjeron una respuesta en las antenas de los machos de C. pomonella, mientras que tan solo el cinamato de alilo la produjo en las antenas de hembras de C. pomonella y en machos y hembras de L. botrana. Esta respuesta no se tradujo en un aumento de la atracción de machos hacia cebos con mezclas de ester de alilo y feromona en ensayos de túnel de viento, pero si aumentó el número de hembras atraídas. Este hecho podría utilizarse par incrementar el número de hembras capturadas en trampas de feromona. Estos resultados, sugieren el papel de los esteres de alilo en el control de plagas, especialmente del cinamato de alilo.
15
Arnosti, André. "Ação dos ésteres do ácido ricinoléico do óleo de mamona nas glândulas salivares e nos ovários de carrapatos Rhipicephalus sanguineus (Latreille, 1806) (Acari : Ixodidae). Análise histológica /". Rio Claro : [s.n.], 2011. http://hdl.handle.net/11449/87703.
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Orientador: Maria Izabel Camargo MathiasBanca: Gislaine Cristina Roma
Banca: Gilberto Orivaldo Chierice
Banca: Roberta Cornelio Ferreira Nocelli
Banca: Gervasio Henrique Bechara
Resumo: O presente trabalho traz informações que mostram a interferência dos ésteres do ácido ricinoléico extraídos do óleo de mamona (Ricinus communis), no ciclo secretor das glândulas salivares e na vitelogênese de fêmeas do carrapato Rhipicephalus sanguineus, agindo diretamente nos processos de alimentação e de reprodução, respectivamente. Para a realização deste estudo, coelhos hospedeiros infestados com carrapatos, foram alimentados com ração comercial comum (controle-GC) e com ração enriquecida com os ésteres em diferentes concentrações (tratamento- GT). As glândulas salivares sofreram danos, e tiveram o citoplasma das células acinares alterado, trazendo prejuízos ao seu funcionamento, além desta substância ter acelerado a degeneração do órgão como um todo. Os ésteres interferiram na atividade de secreção celular alterando a composição da glicoproteína salivar, especialmente nas células glandulares dos ácinos II. O efeito dos ésteres na vitelogênese foi observado nos ovócitos dos carrapatos do grupo tratamento (GT), os quais apresentaram células germinativas com alterações citoplasmáticas, inibição do desenvolvimento dos ovócitos I e II para os estágios avançados (IV e V), além da interferência na maturação dos ovócitos V. Além disso, nas ampolas dos ovários dos indivíduos tratados, espermatozóides não foram observados no seu interior confirmando a ação dos ésteres no processo de reprodução. Ficou demonstrado também que os danos causados pelos ésteres nas células das glândulas salivares e dos ovários desses ectoparasitas, aumentaram na mesma proporção que houve aumento das concentrações do produto, provocando intensa degeneração dos órgãos
Abstract: The present study brings information which shows the interference of ricinoleic acid esters extracted from castor oil (Ricinus communis) on the secretory cycle of Rhipicephalus sanguineus female ticks' salivary glands and vitellogenesis, acting directly on the feeding and reproduction processes respectively. To perform this study, host rabbits were infested with ticks, fed with regular commercial rabbit food (control-CG) and with food enriched with ester in different concentrations (treatment- TG). The salivary glands were damaged and had the cytoplasm of acinar cells altered, impairing their functioning, and the toxic substance also accelerated the degeneration of the organ as a whole. The esters interfered in the cellular secretion activity altering the composition of salivary glycoproteins, especially in the glandular cells of acini II. The effect of the esters in the vitellogenesis was observed in the oocytes of ticks belonging to the treatment group (TG), whose germinative cells presented cytoplasmic alterations, inhibition of the development of oocytes I and II for advanced stages (IV and V) and interference in the maturation of oocytes V. In addition, spermatozoa were not observed in the interior of the ovaries ampoules, confirming the acaricidal potential of the esters. It was also demonstrated that the damages caused by esters in the salivary glands cells and ovary cells of these ectoparasites increased in the same proportion of the increase in the concentrations of the toxic product, causing intense degeneration of the organs
Mestre
16
Alezra, Valérie. "Nouvelles voies d'accés à des sérines alpha-substituées énantiopures à partir d'aziridino-esters ou d'oxazolidino-esters". Paris 5, 2000. http://www.theses.fr/2000PA05P614.
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Mudholkar, Seema. "Effect of oleic acid esters on the microencapsulation of 5-fluorouracil by poly(ortho esters) polymer". Scholarly Commons, 1998. https://scholarlycommons.pacific.edu/uop_etds/2345.
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The investigation focussed on the effects of oleic acid esters on the microencapsulation characteristics of the poly( ortho esters) polymer and their role as potential latentiated acid catalysts for the hydrolysis of the polymer backbone thereby influencing release of 5-fluorouracil. Four oleic acid esters, viz., ethyl oleate, propyl oleate, butyl oleate and lauryl oleate were studied. The microspheres were prepared by the emulsion solvent evaporation technique using sorbitan sesquioleate (6.44%w/w) as the surfactant. The microspheres were prepared with a theoretical drug loading of between 13 and 14% by weight and ester loading of 2.46% by weight with respect to the non-volatile components of the system. All the oleic acid esters (2.46% by weight) were found to retard the release of 5-fluorouracil from the microspheres. The maximum control over drug release was offered by ethyl oleate. Ethyl oleate was also found to give the highest percent entrapment of the drug in the microspheres. The release of 5-FU from the microspheres was inversely related to the concentration of ethyl oleate over the concentration range of 0.72% to 2.46% by weight. Gel permeation chromatography, scanning electron microscopy and the in vitro release data suggested that release of 5-FU from the microspheres occurred by a combination of diffusion and polymer erosion. The polymer erosion was further complicated by the by products of ester hydrolysis. Steady state drug release after the lag phase was zero-order. This suggested that polymer degradation in the steady state region erosion process initiated by oleic acid produced as a result of hydrolysis of the oleic acid ester during the release process.
18
Mohammadi, Farahnaz. "Total synthesis of lavendamycin esters and analogs". Virtual Press, 1993. http://liblink.bsu.edu/uhtbin/catkey/865964.
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The purpose of this research was to synthesize 7-bromodeaminolavendamycin methyl ester (11), deaminolavendamycin methyl ester (19), 7-N-isobutyryldemethyllavendamycin methyl ester (54), 7-N-acetyldemethyllavendamycin ethyl ester (64), 7-Nisobutyryldemethyllavendamycin butyl ester (76), 7-N-isobutyryldemethyllavendamycin tbutyl ester (78), 7-N-cetyldemethyllavendamycin phenyl ester(79), and 7-Nisobutyryldemethyllavendamycin isopropyl ester (80).Lavendamycins 54, 64, 76, 80 were synthesized via the Pictet-Spengler condensation of the corresponding tryptophan esters with 7-N-acetamido-2-formylquinolinedione (91) or 7-N-isobutyramido-2-formylquinolinedione (92). 3-Carbomethoxy-l-( 8-hydroxyquinoline2-yl )-4-methyl-(3-carboline (18), and 3-carbomethoxy-l-(5-acetamido-8-acetoxy-7bromo-2-yl)-4-methyl-(3-carboline (109) were also prepared through the Pictet-Spengler condensation of p-methyl tryptophan methyl ester with 2-formyl-8-hydroxyquinoline (103) and 5-acetamido-8-acetoxy-7-bromo-2-formylquinoline (108), respectively.Compounds 18 and 109 were oxidized by potassium dichromate or Fremy's salt to give deaminolavendamycin methyl ester (19) and 7-bromodeaminolavendamycin methyl ester (11) respectively.7-Isobutyramido-2-formylquinoline-5,8-dione (92) was prepared according to the following general procedure. 8-Hydroxy-2-methylquinoline (26) was reacted with a 70% mixture of HNO3 / H2SO4 to produce 8-hydroxy-2-methyl-5,7-dinitroquinoline (39). Compound 39 was reduced by H2 / Pd-C and then reacted with isobutyric anhydride in the presence of sodium sulfite and sodium acetate to produce 88. Recrystallization of 88 with methanol gave 5,7-diisobutyramido-8-hydroxy-2-methylquinoline (98). Compound 98 was suspended in acetic acid and oxidized by a solution of potassium dichromate to give 7isobutyramido-2-methylquinoline-5,8-dione (90). The dione derivative 90 was oxidized by selenium dioxide in 1,4-dioxane to yield the target aldehyde 92. 2-Formyl-8hydroxyquinoline (103) was synthesized through a selenium dioxide oxidation of 8hydroxy-2-methylquinoline (26).Ester 96 was prepared by the Fischer esterification of L-tryptophan with an excess amount of isopropyl alcohol in the presence of dry HCI. L-Tryptophan phenyl ester (97) was prepared through a two-step reaction. NCBZ-L-tryptophan (101) was treated with phenol and BOP reagent in the presence of triethylamine in acetonitrile to yield NCBZ-L tryptophan phenyl ester (102). The N-protected ester was reduced to L-tryptophan phenyl ester (97) by ammonium formate in the presence of palladium on charcoal in N,Ndimethylformamide. Esters 93-95 were obtained by the treatment of their commercially available hydrochloride salts with 14% NH4OH and then extraction with ethyl acetate.The structures of the compounds 11, 18, 19, 54, 64, 76, 80, 88, 90, 92, 96, 97, 98, 102, 103, 106, 108 and 109 were comfirmed through tH NMR, IR, and MS. Elemental analyses of 90, 92, 96, 98, 103 and 106 and HRMS of 98, 19, 54, 76, 95, 109 are also included. 1H NMR are also provided for compounds 39, 94,95.Department of Chemistry
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Helm, Matthew D. "Heteroaromatic Boronic Esters Through Alkynylboronate Cycloaddition". Thesis, University of Sheffield, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485124.
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Painter, Susan Elizabeth. "Anaerobic biodegradation of phthalic acid esters". Thesis, Georgia Institute of Technology, 1989. http://hdl.handle.net/1853/25185.
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Smyth, G. Darren. "Asymmetric synthesis via #beta#-amino esters". Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297678.
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Mujtaba, Nadeam. "Homochiral heterocycles from β-amino esters". Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.418480.
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Drayton, Sally Katherine. "Palladium-catalysed cyclisation of allylic esters". Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358604.
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Strickland, Gary. "Epoxide polymerisations initiated by metaborate esters". Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.263661.
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Coulbeck, Eliot. "Parallel kinetic resolutions using active esters". Thesis, University of Hull, 2009. http://hydra.hull.ac.uk/resources/hull:2401.
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Obtaining enantiomerically pure compounds is of major importance in modern organic chemistry; the resolution of racemic compounds is a very useful and practical method of achieving this. Parallel kinetic resolutions are an interesting variation on the more classical resolution methods; this method has been recently introduced to the scientific community by Vedejs and there are currently very few examples of successful parallel kinetic resolutions in the literature.The aim of the project, outlined in this report, was to investigate the use of parallel kinetic resolution methodology to resolve racemic carboxylic acids and secondary alcohols. This aim was achieved and in total four distinct parallel kinetic resolution methods were developed; one for the resolution of carboxylic acids, one for the resolution of secondary alcohols, and two that can be used to resolve either carboxylic acids or secondary alcohols. The development process is described for each of these distinct resolutions and their relative scope and limitations are discussed. This report also details the possible reasons for the levels of selectivity found in these reactions, and discusses what effect the reaction conditions have on the level ofstereocontrol. Similarities between all four of the resolutions are described, and the possibility of a generic stereoselective pathway is discussed.This report however is not limited only to findings directly related to parallel kinetic resolutions; it also encompasses all findings from the above mentioned studies. As such, it also describes an unusual observation; the fact that the sign of optical rotation for the common resolving agent 4-isopropyl oxazolidinone is solvent dependant. The discovery and further exploration of a method for synthesising a range of optical pure secondary alcohols from the commercial available (S)-enantiomer of 1- (2-bromo-phenyl)-ethanol is also described. An interesting method for the determination of enantiomeric excess of carboxylic acids is also discussed.
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Pullen, Roger. "Poly(itaconate) esters as marine antifoulants". Thesis, Southampton Solent University, 1998. http://ssudl.solent.ac.uk/2436/.
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A series of fluorinated and non-fluorinated poly(mono- and diitoaconate)s and a perfluorinated acrylate, poly(2-(N-ethylperfluorooctanesulfanamido)ethyl acrylate) have been synthesised, by both solution and bulk chain growth polymerisation methods, characterised and some of their properties (thermal behaviour, surface energy and marine antifouling peformance) have been investigated. Chemical structures were confirmed by Gourier-transform infrared (FTIR) and nuclear magnetic resonance (1H & 13C NMR) spectroscopies, as well as mass spectrometry. Poly(itaconate)s prepared by solution chain growth polymerisation resulted in low average relative molecular mass (Mw <15000), whereas those prepared by bulk chain-growth polymerisation were of high average molecular mass (Mw ca 60000). The thermal degradation behaviour of polu(monoitaconate)s, Mwca60000, was dominated by dehydration/de-esterification reaction at ca 170 deg.C which yielded a poly(anhydride) structure. Poly(diitaconate)s Mwca 60000, were thermally stable up to ca 285 deg.C above which a chain-unzipping process resulted in the formation of monomer as the major degradation product. Glass transition temperatures (Tg) were not observed for poly(monotaconate)s; for poly(hexanoyl diitaconate) Tg was ca -18 deg.C whereas poly(1H,1H,2H,2H-perfluorodecanoyl diitaconate) exhibited two glass transition temperatures, attributed respectively to the relaxation of the alkyl side chain (ca 5 deg.C) and the overall polymer transition (ca 35 deg.C). Poly(hexadecanoyl diitaconate) was the only dditaconate to exhibit a melting endotherm. Surface energy contributions were calculated using the surface tension component (Good-Girafalco-Fowkes) theory. Recently-advanced and recently-receded contact angle measurements were performed at 25.0 + or - 0.2 deg.C for drops of water, diiodomethane and ethylene glycol on the itaconates that could be formed into films. Both recently-advanced and recently-retarded contact angles demonstrated the time-dependency of the wetting behaviour for drops of water, attributed to the slow, stepwise absorption of water by the polymer. Contact angles for drops of diiodomethane and ethylene glycol remained constant over time. Poly(1H,1H,2H,2H-perfluorodecanoyl diitaconate), PI-2, possessed the most hydrophobic surface (initial recently-advanced water contact angle: ca 120 degrees), whereas the least hydrophobic material was poly(hexadecanoyl diitaconate), PH-2; initial recently-advanced contact angle: ca 96 deg. Poly(1H,1H,2H,2H-perfluorodecanoyl diitaconate), PI-2, exhibited the lowest surface energy (advanced ca 7 mJm-2; receded: mean 9.7 mJm-2), whereas poly(hexadecanoyl diitaconate), PH-2 had the highest (advanced: ca 31-37 mJ m-2; receded 39.7 mJm-2). Poly(dodecanoyl monoitaconate), PA-5/6 exhibited surface energies of ca 22 mJ m-2 (advanced) and ca 31 mJ m-2 (receded). The low surface energy of poly(1H,1H,2H,2H-perfluorodecanoyl diitaconate), PI-2 is attributed to both the high hydrophobicity of the surface and the presence of pendent fluorocarbon side chains, which prevent the interaction of diiodomethane molecules with the polymer backbone. The relatively high surface energy of poly(hecadecanoyl diitaconate), PI-2, is due to the lower contact angles measured for this material. Increases in the basic contribution over time and its larger value relative to corresponding acidic contributions are attributed to the uptake of water by the polymer; hydrogen bonding with oxygen atoms of the ester linking group may provide the driving force behind the observed phenomenon. Antifouling performances were evaluated in seawater exposure trials over two fouling seasons. The sequence of fouling events was similar in both seasons: initial settlement by barnacles and algae follwed by settlement of tunicates. In the 1995 exposure trial polymers prepared by solution chain-growth polymerisation as well as a selection of commercial materials were evaluated. All samples exhibited almost no resistance to marine fouling. Suggested contributory factors to their poor performance was their low average relative molecular mass (Mw <15000), a variability of sample coatings or the ineffectiveness of the samples against the inhibition/prevention of settlement/attachment by marine fouling organisms. In the 1996 trial, high average molecular mass poly(itaconate) films prepared by bulk chain-growth polymerisation reactions were exposed. Poly(dodecanoyl monoitaconate)(PA-6), poly(1H,1H,2H,2H-perfluorodecanoyl monoitaconate) (PE-6) and poly(hexadecanoyl diitaconate) (PH-2) exhibited slight resistance to marine fouling, with resistances for these materials after seven months of exposure, of 13%, 18% and 34% respectively (control surfaces had fouling resistances of -5%). Areas free from coverage by fouling organisms were observed on all samples. The overall low resistance of poly(itaconate) can most likely be attributed to the absorption of water by these polymer films.
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Burns, Christine Elizabeth. "Heterogeneously catalysed preparation of ketophosphonate esters". Thesis, Queen's University Belfast, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326407.
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Saket, M. M. "Percutaneous absorption of some steroid esters". Thesis, Cardiff University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372583.
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Khan, Ghulam Ahmed. "Enzymatic synthesis of L-DOPA esters". Thesis, University of Reading, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333598.
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Bryant, Jonatham James Lloyd. "Investigations of commercial cyclic aromatic esters". Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387552.
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Anhoury, Roland. "Les esters en thérapeutique médicamenteuse humaine". Paris 5, 1995. http://www.theses.fr/1995PA05P239.
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Bouillon, Camille. "Synthèse de dendrimères poly(amino)esters". Aix-Marseille 2, 2009. http://theses.univ-amu.fr.lama.univ-amu.fr/2009AIX22073.pdf.
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Les dendrimères représentent une nouvelle classe de composés organiques utilisés dans de nombreux domaines d’application tels que la médecine, et notamment, grâce à leur architecture sphérique parfaitement ordonnée, définie et hyperbranchée. Sur la base de nos récents résultats très prometteurs avec les dendrimères PAMAM pour le transfert de siARN et d’ADN, et afin d’améliorer l’efficacité et la biocompatibilité de ces vecteurs non viraux, nous avons développé des dendrimères biodégradables susceptibles d’être dégradés in vivo par hydrolyse enzymatique ou par variation de pH. Pour la synthèse de cette nouvelle famille de dendrimères poly(amino)esters, nous avons envisagé deux stratégies de synthèses : l’une reposant sur la croissance du dendrimère via la formation de la liaison par addition de Michael, et l’autre reposant sur la construction du dendrimère via la formation de la liaison ester entre un acide et un alcool. Enfin nous avons mis au point une méthode originale et efficace en trois étapes pour préparer nos dendrimères poly(amino)esters : une étape d’activation des fonctions carboxyliques, puis une étape de transestérification avec l’alcool adéquat suivi d’un piégeage de l’excès d’alcool. Ainsi nous avons obtenu des dendrimères de petites générations possédant 12 fonctions esters tert-butyliques, acides ou amines en périphérieDendrimères represents a new class of organic compounds used in several domains of application such as the medicine, in particular, thanks to their perfectly ordered, defined and hypertrendy spherical architecture. On the basis of our recent and very promising results with PAMAM dendrimers for the transfer of siARN and of DNA, and to improve the efficiency and the biocompatibility of these non viral vectors, we have developed biodegradable dendrimers “susceptible” to be degraded in vivo by enzymatic hydrolysis or by variation of pH. For the synthesis of this new family of poly(amino)ester dendrimers, we envisaged two strategies of syntheses: the one basing on the growth of the dendrimer via the amine formation by Michaël addition, and the other one basing on the construction of the dendrimer via the ester formation by the reaction between an acid and an alcohol. Finally we developed an original and efficient method according to three step sequence to prepare our poly(amino)ester dendrimer using an activation of the carboxylic functions, then a transesterification with the adequate alcohol followed by a scavenging of the excess of alcohol. So we obtained dendrimers of small generation having 12 tert-butyl esters, acid functions or amines in surface
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Colin, Sylvie. "Nouveaux accès aux esters α-aminoboroniques". Rouen, 1999. http://www.theses.fr/1999ROUES026.
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Ce travail présente une étude sur de nouvelles synthèses d'esters α-aminoboroniques en vue de la préparation du S18326, un inhibiteur de la thrombine développé par les laboratoires Servier. Deux stratégies générales ont été étudiées pour accéder à ces composés, reposant sur une séquence déprotonation / borylation ou sur une hydroboration. La séquence déprotonation / borylation en α d'halogène, d'oxygène, ou d'azote nous a permis d'obtenir les α-halo, α-alkoxy, et α-aminoboronates souhaités. Le meilleur résultat a été obtenu en déprotonant en α d'azote hétérocyclique. La déprotonation / borylation de la Boc-pyrrolidine ou pipéridine, suivie de sa transestérification par le pinanediol conduit à l'α-aminoboronate attendu avec un rendement de 48 à 56 %. L'étape-clé permettant d'obtenir les esters αα-aminoboroniques chiraux, par déprotonation en présence de spartéine, a également été mise au point et conduit au boronate attendu présentant un excès diastéréoisomérique de 92%. La dernière étape, reposant sur l'addition d'un amidure de lithium de la dibenzylamine, reste à mettre au point. La stratégie de synthèse reposant sur l'hydroboration d'alcènes fonctionnalisés nous a permis d'obtenir les α-halo, α-alkoxy, et α-aminoboronates souhaités. Les α-haloboronates ont été obtenus par hydroboration catalytique des dihalopropènes et ce avec des rendements de 47-70 %. La transestérification de ces composés par le pinanediol nous a permis d'obtenir des composés plus stables avec des rendements de 80 %. L'hydroboration de la dibenzylallylamine nous a permis de proposer une synthèse du S18326, inhibiteur de la thrombine, en introduisant dès la première étape le groupe amino terminal. L'hydroboration de la dibenzylallylamine a été effectuée régiosélectivement. Sa transestérification par le pinanediol suivie de l'homologation de Matteson a été effectuée pour la première fois avec une amine en position terminale et a permis d'aboutir, après substitution par le LiHMDS et hydrolyse, a l'α,delta-diaminobutylboronate de pinanediol, précurseur du S18326. La synthèse a ensuite été achevée par la Société Oril-Industrie. Cette voie de synthèse pourrait donc constituer une alternative à la synthèse actuellement utilisée par Oril-Industrie. Les α-alkoxyboronates ont enfin été obtenus pour la première fois par hydroboration catalytique du 2,3-dihydrofurane, par le pinacolborane sous haute pression.
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Kirkham, James. "Alkynylboronate cycloadditions towards aromatic boronic esters". Thesis, University of Sheffield, 2011. http://etheses.whiterose.ac.uk/2107/.
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Ben, Halima Taoufik. "Engaging Esters as Cross-Coupling Electrophiles". Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/39493.
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Cross-coupling reactions, where a transition metal catalyst facilitates the formation of a new carbon-carbon or carbon-heteroatom bond between two coupling partners, has become one of the most widely used, reliable, and robust family of transformations for the construction of molecules. The Nobel Prize was awarded to pioneers in this field who primarily used aryl iodides, bromides, and triflates as electrophilic coupling partners. The expansion of the reaction scope to non-traditional electrophiles is an ongoing challenge to enable an even greater number of useful products to be made from simple starting materials. The major goal of this thesis research is to improve and expand upon this field by using esters as electrophiles via the activation of the strong C(acyl)−O bond. Esters are particularly robust in comparison to other carboxylic acid derivatives used in cross-coupling reactions. Success on the activation of such inert functional group using catalysis has both fundamental and practical value. By discovering new reaction modes of this abundant functional group, synthetic routes to access novel or industrially important molecules can be improved.
Chapter 1 of this thesis describes a literature overview of what has been accomplished in the field of cross coupling reactions using carboxylic acid derivatives as electrophilic coupling partners.
Chapter 2 discloses the first palladium Suzuki-Miyaura couplings of phenyl esters to produce ketones. The method is efficient and robust, giving good yields of useful products. The reaction is proposed to proceed via an oxidative addition to the strong C(acyl)−O bond of the ester. In contrast to previous efforts in this field that use traditional catalysts such as Pd(PPh3)4, the developed reaction requires use of an electron-rich, bulky N-heterocyclic carbene ligand, which facilitates the strong bond activation.
Furthermore, a palladium-catalyzed cross-coupling between aryl esters and anilines is reported, enabling access to diverse amides. The reaction takes place via a similar activation of the C−O bond by oxidative addition with a Pd−NHC complex, which enables the use of relatively non-nucleophilic anilines that otherwise require stoichiometric activation with strong bases to react.
Chapter 3 discloses a nickel-catalyzed amide bond formation using unactivated and abundant esters. In this transformation, an accessible nickel catalyst can facilitate the activation of diverse aliphatic and aromatic esters to enable direct amide bond formation with amines as nucleophiles. No stoichiometric base, acid, or other activating agent is needed, providing exceptional functional group tolerance and producing only methanol as a by-product. This reaction is of both fundamental and practical importance because it is the first to demonstrate that simple conditions can enable Ni to cleave the C–O bond of an ester to make an oxidative addition product, which can be subsequently coupled with amines. This discovery contrasts industrially-common and wasteful methods that still require stoichiometric activating agents or multistep synthesis.
Chapter 4 describes the evaluation of different types of cross-coupling reactions using methyl esters as electrophilic coupling partner. A high-throughput screening technique has been applied to this project. A combination between specific ligands, known by their efficiency to activate strong C−O bonds, and literature-based conditions has been designed for the chosen transformations. Using this strategy, two promising hits have been obtained using the same NHC ligand: a decarbonylative Suzuki-Miyaura and a decarbonylative borylation reaction.
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Rigo, Davide <1994>. "Synthesis and applications of isopropenyl esters". Master's Degree Thesis, Università Ca' Foscari Venezia, 2018. http://hdl.handle.net/10579/13861.
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A general solvent-free protocol for the synthesis of isopropenyl esters (iPEs) was developed and applied to different renewable based carboxylic acids and their acyl chlorides derivatives, relying on the use of sulfuric acid as catalyst. Isopropenyl acetate, a potentially renewable, cheap and non-toxic reagent, was used as “isopropenyl synthon source” for the synthesis of isopropenyl esters. Benzoic, p-methoxy benzoic, octanoic, phenylbutirric, levulinic, oxalic, malonic and succinic acids were used. Furthermore, Brønsted acid ionic liquids (BAILs) were tested for the synthesis of iPEs.
The protocol could also be extended to dicarboxylic acids, e. g. oxalyl chloride and succinyl chloride, upon simple modifications of the reaction setup (reaction performed in presence of a solvent using a heterogeneous acid catalyst).
Some of these synthesized iPEs (isopropenyl benzoate, octanoate and phenylbutyrate) and iPA were let react with 1,2-propanediol and ethylene glycol, under resin Amberlyst-15 catalysis, in order to study their reactivity. The aim was to obtain simultaneously the respective monoesters and acetals, exploiting the production of acetone by-product during the transesterification process. A comparison among the tested isopropenyls towards this tandem-type reaction was obtained.
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HARRATA, ABDELKAMEL. "Reactivite en phase gazeuse de cations radicaux : ceto-esters et dioxolannes-esters et de cations acylium substitues". Paris 6, 1989. http://www.theses.fr/1989PA066708.
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La reactivite d'ions bifonctionnels de faible energie interne: des ceto-esters ionises ch#3co(ch#2)#nco#2ch#3, de ions acylium ch#3co(ch#2)#nco#+ et co(ch#2)#nco#2ch#3#+ n=2 a 5; du methyl-2 dioxolanne-2 propanoate de methyle ionise est etudiee en phase gazeuse a l'aide des techniques de spectrometrie de masse. L'interpretation du comportement de ces ions (fragmentations precedees ou non d'isomerisations) s'appuie sur: l'analyse des decompositions unimoleculaires et bimoleculaires d'ions dont la duree de vie est de l'ordre de 10##5 s et l'utilisation de composes marques aux isotopes stables (deuterium, oxygene dix huit, carbone treize). Les resultats les plus significatifs sont les suivants: 1) les ceto-esters ionises se fragmentent essentiellement par ruptures homolytiques de differentes liaisons en et des groupes fonctionnels; 2) les ions acylium co(ch#2)#nco#2ch#3#+ s'isomerisent avant fragmentation par transfert 1, n+2 du groupe methoxyle rendant les deux fonctions carbonyles equivalentes; 3) les ions acylium ch#3co(ch#2)#nco#+ s'isomerisent avant fragmentation en ions (m-1)#+ de lactones ce qui a pour consequence de rendre indiscernable les deux atomes d'oxygene
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Ramiandrasoa, Guy. "Etude de l'accès sélectif aux esters 2,3-difonctionnels". Rouen, 1993. http://www.theses.fr/1993ROUES017.
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Plusieurs voies d'accès aux esters 2,3-difonctionnels ont été évaluées dans les séries dihydroxy- et aminohydroxyesters en raison de l'importance des produits naturels correspondants ou de leurs homologues synthétiques. Les précurseurs de ces synthèses sont les α et β cétoesters fonctionnels et leurs formes protégées ainsi que les dérivés silylés des dialkoxyacétates d'alkyle, acétals de cétène silylés fonctionnels qui représentent les équivalents synthétiques des synthons C2 oxoester « CO-COOR ». L'étude structurale des composés préparés est axée sur la RMN 1H et 13C ainsi que sur les caractéristiques des spectres de masse et fait l'objet d'un développement particulier
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Paracatu, Luana Chiquetto [UNESP]. "Ácido cafeico e seus ésteres: inibição do burst oxidativo de neutrófilos e efeito anti-Helicobacter pylori". Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/93126.
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Universidade Estadual Paulista (UNESP)
A ação patogênica do Helicobacter pylori envolve a colonização do trato gastrointestinal e a produção de EROs por neutrófilos atraídos e ativados pelo agente da infecção. A reação mediada pelos PMN é, todavia, ineficaz para eliminar o H. pylori e as EROs contribuem para a lesão tecidual e desenvolvimento de gastrites e úlcera péptica. O ácido cafeico é um dos mais importantes compostos fenólicos, e apresenta diferentes propriedades biológicas, entre elas antioxidante e antimicrobiana. O objetivo deste estudo foi avaliar a atividade antioxidante e anti-H.pylori do ácido cafeico e seus ésteres. Foram avaliados os ésteres: cafelato de metila, cafelato de butila e cafelato de heptila e realizada uma comparação entre as propriedades antioxidantes do ácido cafeico e tais ésteres, por meio de ensaio de quimiluminescência dependente de luminol e lucigenina, ensaio de inibição da produção do ácido hipocloroso e também ensaios morfológicos com e sem a presença de NBT. Os resultados deste estudo mostraram que os ésteres do ácido cafeico apresentaram melhores resultados em comparação com o ácido cafeico para a capacidade antioxidante. O cafelato de heptila apresentou os melhores resultados para a quimiluminescência dependente de luminol e lucigenina induzida por H. pylori e/ou zymozan opsonizado na concentração de 10 µM e 1 µM . O efeito do ácido cafeico e seus ésteres, também foi estudado na inibição da produção de ácido hipocloroso por neutrófilos ativados com PMA. O cafelato de heptila novamente provou ser melhor em capacidade antioxidante, levando a crer que a lipofilicidade deste composto...
The pathogenic action of Helicobacter pylori involves the colonization of the gastrointestinal tract and ROS production by neutrophils attracted and activated by the agent of infection. However, the reaction mediated PMN is ineffective to remove the H. pylori and ROS contribute to tissue damage and development of gastritis and peptic ulcer. Caffeic acid is one of most important phenolic compounds, and has different biological properties including antioxidant and antimicrobial activities. The aim of this study was to evaluate the antioxidant and anti-Helicobacter pylori activity of caffeic acid and esters. Esters evaluated: methyl caffeic acid ester, butyl caffeic acid ester and heptyl caffeic acid ester and a comparison between the antioxidant properties of caffeic acid and these esters through luminol and lucigenin chemiluminescence assay dependent, inhibition of production of hypochlorous acid assay, morphological tests with and without the presence of NBT. The results of this study showed that the esters of caffeic acid had better results in comparison with caffeic acid to their antioxidant capacity. The heptyl caffeic acid ester showed the best results for the luminol and lucigenin dependent chemiluminescence induced by H. pylori and / or opsonized zymozan in the concentrations of 10 µM and 1 µM. The effect of caffeic acid and esters, was also studied in inhibiting of production of hypochlorous acid by neutrophils activated with PMA. The heptyl caffeic acid ester again proved to be better at antioxidant activity, implying that... (Complete abstract click electronic access below)
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Rajagopal, Thivisa. "Synthesis of Single Isomer Trisubstituted Olefins from beta-chloro-alpha-iodo-alpha, beta-Unsaturated Esters and Alkynyl Esters". Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28552.
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A convenient method to synthesize regiospecific and stereoselective trisubstituted olefins bearing three substitutents with various functionalities is disclosed. A unique olefin template such as (E)-beta-chloro-alpha-iodo-alpha,beta-unsaturated esters cross-couple with 9-alkyl-9-BBN to produce single isomer trisubstituted olefins using palladium-catalyzed Suzuki-Miyaura cross-coupling reaction. This methodology can be further expanded to introduce various alkyl groups at the beta-position. The mechanism is somewhat unusual as it involves two catalytic cycles with an allenoate intermediate to explain the observed stereochemistry and protonolysis of that intermediate produces the key product, (E)-beta-chloro-alpha,beta-unsaturated ester. The protonolysis is mediated by the presence of H2O in the inorganic base, K3PO4·H2O.*
Similarly, another method has been developed to synthesize trisubstituted olefins using the alkynyl ester and 9-alkyl-9-BBN. This process also has a broad scope to introduce various alkyl groups at the beta-position. The mechanism currently proposed involves an oxidation of palladium to form H-[Pd]-OH species. This was confirmed based on the importance of water in the catalytic system and the isotopic experiments also confirmed the olefinic hydrogen at the alpha-position arises from the water itself. Following the formation of H-[Pd]-OH, syn carbopalladation to the alkynyl ester creates the hydroxyl palladium vinyl intermediate. However, this mechanism does not explain the observed stereochemistry. A more detailed study is required regarding this mechanism.*
*Please refer to dissertation for diagrams.
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Nelson, Keegan Gregory. "Enantioselective hydrolysis of 1-arylpropargylic esters by enzymatic kinetic resolution and dynamic kinetic resolution of 1-arylallylic esters". Thesis, University of Missouri - Kansas City, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1538847.
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Chiral 1-arylprop-2-en-1-ols and 1-arylprop-2-yn-1-ols are useful building blocks for modern pharmaceuticals. Previous work has found that enzyme catalysis is a potential new enantioselective synthetic route to the former. We found that Candida antarctica lipase is also an effective catalyst for kinetic resolution of various substituted 1 arylpropargylic acetates and haloacetates, affording the respective (R) -1 arylproargylic alcohols with high enantioselectivity (99-100% ee). By varying the substituents on both sides of the ester bond, we discovered that the deacylation of lipase is likely the rate-determining step for our catalytic system. A greater challenge is designing a dynamic kinetic resolution (DKR) system for such substrates, which combines a resolving catalyst (lipase) with a racemizing catalyst, and can potentially lead to quantitative conversion of a racemic substrate into an enantiopure product. We studied the efficacy of various transition-metal complexes for substrate racemization and will report our results for In and Cu compounds.
While kinetic resolution has been performed on the 1-arylallylic acetates with excellent yield and enantioselectivity and the DKR regime has been designed, the resulting site-isolation system has required further testing and fine tuning. We have herein investigated the utilization of macroscale site-isolation as well as various factors including solvent, and acyl donor effects in order to optimize conditions of the system.
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Cavalli, Fabrizia. "Atmospheric oxidation of selected alcohols and esters". [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=962378763.
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Safranski, David Lee. "Poly(beta-amino esters) for cardiovascular applications". Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42825.
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Abdominal aortic aneurysms are a leading cause of death in the U.S. where 14,000 people die from aneurysm rupture and 178,000 are diagnosed each year. A novel alternative treatment for abdominal aortic aneurysms has been proposed, where a biodegradable polymer scaffold is photopolymerized in situ around the exterior of the aneurysm. This scaffold will mechanically constrain the aneurysm from further expansion, and will deliver a drug, doxycycline, to treat the underlying biological cause of the disease. In order for device development, a suitable polymer must be designed with appropriate mechanical properties, degradation rate, polymerization, and elution rate. Poly(β-amino ester) networks have been proposed as the material of choice; however, many of their structure-property relationships have yet to be determined.
Therefore, the overall goal of this work is to determine the structure-property relationships of the poly(β-amino ester) networks in order to advance the design of the treatment, and has been divided into three objectives: (1) understand the structure-property relationships of poly(β-amino ester) networks, specifically the polymerization, degradation rate, and thermo-mechanical properties, (2) determine the impact of doxycycline incorporation on degradation rate and mechanical properties, (3) evaluate the effect of simulated physiological conditions on degradation rate and mechanical properties.
In the initial chapters, the fundamental structure-property relationships are established between reactant chemical structure, step-growth polymerization, photopolymerization, thermo-mechanical properties, and degradation rate using a systematic approach of two homologous series of reactants. Further tailoring of degradation rate, water content, and modulus in vitro was performed by using a copolymer network. Doxycycline inhibited photopolymerization due to overlapping absorbance spectra with the photoinitiator, but full network formation occurred by increasing the photoinitiator concentration. Networks displayed varying controlled release rates, and the underlying release mechanism was determined for each network using established methods.
In order to increase mechanical properties, a co-monomer, methyl methacrylate, was added to the network to increase the glass transition temperature, toughness, and deformation capacity. These co-networks displayed temporal-control of mechanical properties in simulated physiological conditions, since degradation caused a shift in the glass transition temperature, which changed the mechanical behavior of the network. The temporal-control of mechanical properties was further investigated under degradation conditions in vitro and in vivo. Due to the mechanically active loading environment in vivo, networks displayed a decrease in toughness, yet maintained mechanical properties similar to native biological tissues. These networks establish a multifunctional biomaterials platform with materials that can be easily synthesized, photopolymerized into various geometries, and sustain mechanical properties while undergoing degradation and therapeutic agent release.
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Velázquez, Janice M. "Conversion of corn oil to alkyl esters". [Ames, Iowa : Iowa State University], 2007.
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Jones, Iwan Gwynedd. "Desymmetrization of meso-anhydrides by proline esters". Thesis, Bangor University, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265515.
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Garrais, S. "Synthesis of Lipid Structures and Matricaria Esters". Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517311.
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McAteer, Elizabeth Ann. "Formation and oxidation reactions of phosphonate esters". Thesis, Queen's University Belfast, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396073.
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Stead, Angela Louise. "Reactions of alkoxyl radicals with aliphatic esters". Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403865.
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