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1
Viola, Angelo <1985>. "Alkylidene malonates and acetoacetates as intermediates for the preparation of bioactive molecules." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6344/1/Viola_Angelo_Tesi.pdf.
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In this thesis we investigated the versatility and the potential applications of different kinds of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides. Our research group devoted great attention to this kind of compounds since alkylidenes can be considered important intermediates in the synthesis of several scaffolds, to be inserted into molecules of potential biological and pharmaceutical interest. The increasing use of alkylidenes is due to their ability to react as unsaturated electrophiles and to the possibility to exploit them as intermediates for the introduction of different kind of functionalities.The preparation of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides is presented in chapter 1.
This section deals with different preparation methods of alkylidenes that we developed during the last few years and to the technologies involved for each synthetic protocol. The reactivity that allowed to use the alkylidenes as intermediates in the synthesis of scaffolds for biologically active compounds is shown in chapter 2. In particular, we will discuss the most important reactions used to obtain the desired molecules, and we will focus on the most interesting aspects of these latter ones.
Finally, chapter 3 will illustrate the potential applications and the related syntheses of potential bioactive compounds. The synthesized molecules find application in several fields and for this reason we considered each class of compounds in its related branch of interest.
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Viola, Angelo <1985>. "Alkylidene malonates and acetoacetates as intermediates for the preparation of bioactive molecules." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6344/.
Full textAbstract:
In this thesis we investigated the versatility and the potential applications of different kinds of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides. Our research group devoted great attention to this kind of compounds since alkylidenes can be considered important intermediates in the synthesis of several scaffolds, to be inserted into molecules of potential biological and pharmaceutical interest. The increasing use of alkylidenes is due to their ability to react as unsaturated electrophiles and to the possibility to exploit them as intermediates for the introduction of different kind of functionalities.The preparation of alkylidene malonates, acetoacetates, malonamides and acetoacetoamides is presented in chapter 1.
This section deals with different preparation methods of alkylidenes that we developed during the last few years and to the technologies involved for each synthetic protocol. The reactivity that allowed to use the alkylidenes as intermediates in the synthesis of scaffolds for biologically active compounds is shown in chapter 2. In particular, we will discuss the most important reactions used to obtain the desired molecules, and we will focus on the most interesting aspects of these latter ones.
Finally, chapter 3 will illustrate the potential applications and the related syntheses of potential bioactive compounds. The synthesized molecules find application in several fields and for this reason we considered each class of compounds in its related branch of interest.
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Marrot, Florent. "Etude des malonates et squarates de lanthanoi͏̈de comme précurseurs des sulfures et oxysulfures correspondants." Toulouse 3, 1994. http://www.theses.fr/1994TOU30207.
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Cette recherche s'inscrit dans le cadre de l'elaboration de materiaux a partir de complexes de coordination, par le biais d'une degradation thermique en atmosphere controlee, a des temperatures aussi basses que possible. L'objectif particulier recherche vise a l'obtention de sulfures de terre-rare a partir des malonates ou squarates de ces elements. Les structures de deux complexes malonate de lanthane penta-hydrate et de deux complexes malonate mixtes de lanthane et de cuivre ont ete determinees. Toutes ces structures presentent des feuillets denses charges positivement dans lesquels le ligand malonate reunit quatre centres metalliques. La connexion entre ces feuillets se fait soit par un anion malonate soit par une entite dimalonate de cuivre. La synthese et l'etude structurale d'un malonate bimalonate de lanthane ont egalement ete realisees. Ce compose presente un caractere monodimensionnel marque. Deux familles de squarates de lanthanoide et d'ammonium, dependant du rayon ionique de la terre-rare, ont ete mises en evidence et leurs structures cristallines determinees. L'une est monodimensionnelle avec developpement de chaines en zigzag, l'autre est bidimensionnelle avec presence de feuillets ; l'electroneutralite est assuree par les ions ammonium. La degradation thermique de ces complexes, sous atmosphere d'azote et de soufre permet d'obtenir les sesquisulfures, phase beta, du lanthane au gadolinium, ou les oxysulfures, du dysprosium a l'ytterbium, par traitement de deux heures a partir de 700c ; ce qui represente un avantage certain par rapport aux methodes conventionnellement employees. La phase haute temperature gamma du sesquisulfure de cerium (1200-1300c) peut etre utilisee en tant que pigment rouge, en remplacement du sulfoseleniure de cadmium qui tend a etre interdit. Nous avons reussi a stabiliser cette phase a l'aide de dopants judicieusement choisis vers 600c et a controler la morphologie des poudres obtenues. Cette partie de la these doit demeurer confidentielle
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Fallan, Charlene. "Ytterbium-catalysed conjugate allylation of alkylidene malonates and enantioselective nickel-catalysed Michael additions of azaarylacetates and acetamides to nitroalkenes." Thesis, University of Edinburgh, 2012. http://hdl.handle.net/1842/7683.
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I. Catalytic Conjugate Allylation of Alkylidene Malonates Nucleophilic conjugate addition of allylsilanes and allylstannanes to alkylidene malonates under the action of ytterbium catalysis in the presence of hexafluoro-isopropanol has been developed. Enantioselective conjugate allylation of alkylidene malonates under ytterbium or scandium catalysis using chiral bis(oxazoline) ligands allows access to the conjugate addition products in an enantiomerically-enriched form. Furthermore, elaboration of the allylated substrates via decarboxylation and an oxidative cleavage was demonstrated. II. Catalytic Enantioselective Conjugate Addition of Azaarylacetates and Acetamides to Nitroalkenes An enantioselective nickel-catalysed Michael addition of azaarylacetates and acetamides to nitroalkenes has been developed. A range of azaaryl pronucleophiles were shown to react with a variety of nitroalkenes to generate highly functionalised Michael addition products with impressive diastereo- and enantiocontrol. A possible mechanism for this process is proposed and crystal structures of the addition products have also been attained, allowing determination of the absolute stereochemistry. Elaboration and further functionalisation of these products was also possible under a range of conditions.
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Ultchak, Flaviana Salles. "Equilibrio liquido-vapor dos sistemas n-butanol : dimetilmalonato ou dietilmalonato as pressões de 100 e 200mmHg." [s.n.], 2000. http://repositorio.unicamp.br/jspui/handle/REPOSIP/267645.
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Orientador: Maria Alvina KrahenbuhlDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica
Made available in DSpace on 2018-08-12T02:24:53Z (GMT). No. of bitstreams: 1 Ultchak_FlavianaSalles_M.pdf: 2164181 bytes, checksum: f1468bdd0cb3489326bd20f27ce9101c (MD5) Previous issue date: 2000
Resumo: Dados de equilíbrio de fases são úteis no projeto e otimização de processos que envolvem separação de fases, como destilação e extração. Malonatos são substâncias orgânicas que atuam como importantes intermediários em várias reações, como na produção de tintas, fármacos, pesticidas e aromas. Mesmo assim, as propriedades físicas dos malonatos são escassas na literatura. Este trabalho tem como objetivo obter as curvas de equilíbrio líquido-vapor isobáricas para três sistemas: dimetilmalonato/n-butanol a 100 e 20OmmHg, dietilmalonato/n-butanol a 200mmHg. Foi utilizado um ebuliômetro de recirculação de fases, da marca comercial "Normag". As concentrações das fases líquidas e vapor foram obtidas por cromatografia gasosa. Observou-se que ocorria uma reação química durante os experimentos, mas que não impediu o desenvolvimento do trabalho. A consistência termodinâmica foi testada pelo método de van Ness-Fredenslund (1977) e os parâmetros de interação binária do coeficiente de atividade para os modelos Wilson, UNIQUAC e NRTL foram estimados pelo método da máxima verossimilhança de acordo com Stragevitch (1997). Apesar da reação química, os dados obtidos são consistentes de acordo com os critérios adotados, mas observou-se que com o aumento da ftação molar do malonato presente, a partir de 0,5, a qualidade dos dados foi prejudicada pela reação química
Abstract: Phase equilibrium data are useful in the project and optimization of process that inc1udes phases separation, such as distillation and extraction. Malonates are organic substances that participate as an important intennediate in production reactions, like as ink, pharmaceuticals, pesticides and ftagrances. However their properties are rare in scientific literature. In this work the isobaric curves ofvapor-liquid equilibrium were measured for three systems: (I) dimethyl malonate+l-butanol at 100 mmHg, (2) dimethyl malonate+l-butanol at 200 mmHg and (3) diethyl malonate+l-butanol at 200 mmHg. Each system was measured by means of an ebuliometer with phase circulation (NORMAG). The liquid and vapor phase concentration was obtained by gaseous chromatography. A chemical reaction was verified during the experiments, but it didn't impede the work development. The thermodynamic consistency of the data was tested using the van Ness-Fredenslund method (1977) and the binary interaction parameters ofthe activity coefficient for the WILSON, UNIQUAC and NRTL models were calculated by the Maximum Likelihood Method in agreement with Stragevitch (1997). However a reaction inside of the equipment occurred during the experimental measurements, the results were considered consistent in agreement with the adopted rules in this work, but was verified that the data quality was impaired by chemical reaction with the increase ofmolar ftaction ofthe malonate, after 0,5
Mestrado
Desenvolvimento de Processos Químicos
Mestre em Engenharia Química
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Pailloux, Sylvie. "Conception, synthèse et évaluation pharmacologique de ligands des PPARs (Peroxisome Proliferator-Activated Receptors)." Lille 2, 2003. http://www.theses.fr/2003LIL2MT22.
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L'obésité, le diabète de type 2 et de nombreuses maladies inflammatoires comme l'athérosclérose, sont des pathologies en forte progression depuis ces dix dernières années. Il apparaît que les PPARs (Peroxisome Proliferator-Activated Receptors) interviennent dans la régulation de gènes influençant ces pathologies. Ces facteurs de transcription s'hétérodimérisent avec un autre récepteur nucléaire RXR (récepteur aux acides rétinoïques), après qu'ils soient activés par leurs ligands. Le complexe formé se fixe sur son PPRE (élément de réponse des PPARs) et recrute de nombreux co-facteurs. A partir de travaux antérieurs, une étude suivant le modèle de Topliss a été réalisé sur des structures diesters maloniques. La nécessité d'obtenir des ligands d'activité mixte PPARα/γ, nous a conduit à moduler l'extrémité malonate des composés précédents en acides esters, amides esters, acides, amides, nitriles et tétrazoles, en série benzothiazolinone, 6-benzoylbenzothiazolinone et 5-benzoylbenzothiazolinone. L'ensemble de ces molécules a été ou est encore testé, in vitro et in vivo, par les laboratoires SERVIER, afin de déterminer leurs activités sur PPARα et PPARγ, ainsi que leurs effets sur des marqueurs biologiques tel que les triglycérides, le glucose, la résistance à l'insulineObesity, diabetes (type 2), and many inflammatory illnesses such as arthrosclerosis have become pathologies of great interest over the last ten years. It appears that PPARs (Peroxisome Proliferator-Activated Receptors) play a role in the regulation of genes that influence these pathologies. These transcription factors heterodimerize with another nuclear receptor called RXR (Retinoidal X Receptor), after their activation by their ligands. The complex which forms fixes on PPREs (PPAR response elements) and recruits numerous co-factors. From previous work a study following Topliss was undertaken on the malonic diester structures. The need for ligands which have an activity dual PPARα/γ, led us to modulate the extremity of the malonate to acid esters, amide esters, acids, amides, nitrile tetrazoles, to a series benzothiazolinone, and to 5- and 6- benzoylbenzothiazolinone. All of these molecules have or are being tested in vitro and in vivo by the « laboratoires Servier », in order to determine their activities on PPARα and PPARγ, as well as their effects on biomarkers such as triglycerides, glucose, and insulin resistance
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Ahouari, Hania. "Exploration de nouveaux matériaux d'électrodes positives à base de polyanions carboxylates (oxalates, malonates et carbonates) et de métaux de transition." Thesis, Amiens, 2015. http://www.theses.fr/2015AMIE0027/document.
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Dans cette thèse, nous avons exploré toute une palette de composés à base de métaux de transition et de polyanions carboxylates (oxalates, malonates et carbonates) préparés via des procédés éco-efficaces. La synthèse du composé oxalate de fer (III) (Fe2(C2O4)3·4H2O) dont nous en avons élucidé pour la première fois la structure cristalline en combinant les techniques de diffraction des rayons X et neutrons, fait l'objet de la première partie de cette étude. Ce composé cristallise dans une maille triclinique (P -1) et il présente des propriétés électrochimiques intéressantes (98 mAh/g à 3.35 V vs. Li+/Li0). Dans cette quête pour de meilleurs matériaux, nous avons exploré la famille des oxalates Na2M2(C2O4)3·2H2O, dont la synthèse avait été déjà rapportée, mais sans qu'aucune activité électrochimique ne puisse être détectée. En revanche, le remplacement du groupement oxalate par un groupement malonate nous a permis d’obtenir pour la première fois plusieurs membres de la famille (Na2M(H2C3O4)2·nH2O (n=0, 2), M= Mn, Fe, Co, Ni, Zn et Mg) dont nous avons résolu leurs structures cristallines correspondantes. Cependant, comme dans le cas des oxalates, ces phases ne dévoilent aucune activité électrochimique vis-à-vis du lithium, bien qu'elles présentent des propriétés magnétiques intéressantes. Enfin nous avons conclu ce travail par la synthèse de composés appartenant à la famille des fluorocarbonates KMCO3F (M= Ca et Mn) en utilisant la voie tout solide. La phase au calcium, déjà rapportée dans la littérature, a fait l'objet d'une étude en température qui nous a permis de mettre en évidence pour la première fois la formation d'une phase haute température (KCaCO3F-HT), pour T≥320°C, dont nous avons résolu la structure. Finalement, l'utilisation du Mn au lieu du Ca a conduit à l'obtention d'une nouvelle phase (KMnCO3F) qui cristallise dans une maille hexagonale (P -6 c 2)This thesis has focused on the exploration of new compounds based on 3d-metal and carboxylate polyanions (oxalates, malonates and carbonates) prepared through different sustainable synthetic approaches. In the first part, we report a new synthetic route to prepare the iron (III) oxalate compound (Fe2(C2O4)3·4H2O) and solve its crystal structure through combined X-ray and neutron powder diffraction. The compound crystallizes within a triclinic cell (P-1) and exhibits attractive electrochemical properties (98 mAh/g at 3.35 V vs. Li+/Li0). Motivated by this finding we pursued our quest for new positive electrode materials. We prepared by hydrothermal synthesis single crystals of sodium 3d-metal oxalates Na2M2(C2O4)3·2H2O, which are widely investigated in the literature for their magnetic properties. Unfortunately, these phases are electrochemically inactive versus lithium. Thereafter, we extended the synthesis towards the malonate family and we reported for the first time several members (Na2M(H2C3O4)2·nH2O (n= 0, 2), M= Mn, Fe, Co, Ni, Zn et Mg). These systems present rich crystal chemistry together with interesting antiferromagnetic properties but as in the case of the oxalates, they are not electrochemically active versus lithium. Finally, we synthesized two members of fluorocarbonates compounds KMCO3F (M= Ca and Mn) using solid state process. We succeeded in the preparation of the calcium member, already reported in the literature and we identified for the first time a phase transition at 320°C. The crystal structure of the high temperature phase (KCaCO3F-HT) was solved using neutron powder diffraction. A new manganese phase (KMnCO3F) was synthesized using the same technique and its crystal structure was solved by combining TEM, XR and neutrons powder diffraction techniques. This compound crystallizes within a hexagonal unit cell (P -6 c 2)
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Buchanan, D. J. "Diastereoselective oxy-Michael addition of a new chiral water equivalent to electron deficient alkenes : synthesis of 1,2-amino alcohols and b-hydroxy malonates." Thesis, University of Cambridge, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597051.
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Chapters 1 and 2: An introduction to the intermolecular oxy-Michael reaction and a brief overview of the methods used to synthesise 1,2-amino alcohols. Chapter 3: An oxy-Michael reaction was developed whereby the addition of (S)-6-methyltetrahydropyran into a,b-unsaturated monosubstituted nitro compounds allowed rapid access to synthetically important 1,2-amino alcohols. Chapter 4: A logical advancement of the oxy-Michael addition was the addition into a,b-unsaturated disubstituted nitro compounds. These molecules were also converted into the corresponding 1,2-amino alcohols. In addition sequential treatment of the oxy-Michael adduct with TPAP yielded the corresponding b-hydroxy ketone motif. Chapters 5 and 6: The highly stereoselective total syntheses of (R)-pronethalol and (R)-salmeterol were achieved using the new oxy-Michael method as the key step. Chapter 7: An expansion of the methodology to incorporate other conjugate acceptors was considered important. However, analogous d-lactol oxy-Michael additions into crotonate ester and pentenolide were unsuccessful. However, successful oxy-Michael addition into symmetrical a,b-unsaturated malonate systems yielded THP* protected b-hydroxy malonates. It is believed that such motifs shall be capable of transformation into b-hydroxy esters after further development.
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ARZEL, PHILIPPE. "Construction asymetrique de carbones quaternaires benzyliques a partir de malonates et de diols prochiraux : application a la synthese selective d'alcaloides benzomorphanes (aphanorphine, eptazocine, ), de pyrrolidines et de piperidines (picenadol)." Paris 11, 1998. http://www.theses.fr/1998PA112329.
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Le travail rapporte concerne la preparation enantioselective de synthons possedant un carbone quaternaire benzylique chiral de hautes puretes enantiomeriques par voie enzymatique a partir de composes prochiraux (malonates, propane-1,3-diols 2,2-disubstitues, diols bicycliques) ainsi que leur application a la synthese d'heterocycle azotes biologiquement actifs. Dans la premiere partie sont exposees les preparations d'un hemiester chiral par hydrolyse enzymatique et de deux monoacetates benzyliques chiraux par transesterification enzymatique. Les reductions chimioselectives des fonctions acide et ester de l'hemiester permettent de preparer les deux formes enantiomeres de l'aphanorphine et de l'eptazocine, composes de type benzomorphane possedant une activite analgesique. Plusieurs voies d'acces a des alcools di- et tetrahydronaphtaleniques, precurseurs directs de ces composes, sont decrites a partir de l'hemiester et du monoacetate bicyclique respectivement de 97 et 93% d'ee. La synthese totale d'un derive dihydroxyle de l'aphanorphine est exposee. Dans un deuxieme temps, est decrite la preparation de synthons chiraux avec variation de la chaine alkyle (propyle, allyle), de la nature et du nombre des substituants aromatiques (3-methoxy-ou 3,4-dichloro-). La preparation de ces synthons permet une generalisation partielle de la methode de synthese par voie enzymatique. Une etude en modelisation moleculaire sur la reactivite de certains substrats avec l'esterase de foie de porc a ete realisee. L'acide (r)-(+)-2-(methoxycarbonyl)-2-(3-methoxyphenyl)pent-4-enoique, compose obtenu avec la plus grande purete enantiomerique, est utilise pour la synthese d'un ether d'enol, intermediaire commun permettant d'acceder en un seul pot, soit a une pyrrolidine, precurseur direct du profadol, soit a un lactame, precurseur potentiel du picenadol (piperidine). Tous ces composes ainsi que leurs intermediaires possedent de tres bons exces enantiomeriques (ee superieur a 86%).
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Donnici, Claudio Luis. "Caminhos sintéticos para obtenção de ésteres e tioésteres - α-metilsulfonil-α-metiltio-substituídos, precursores dos derivados α-ceto-carbocxílicos correspondentes." Universidade de São Paulo, 1993. http://www.teses.usp.br/teses/disponiveis/46/46135/tde-23062015-131015/.
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Este trabalho apresenta: 1) Duas revisões bibliográficas sendo uma sobre a síntese de α-ceto-tioésteres e -ésteres e a outra sobre a decomposição de sulfóxidos e sulfonas sulfeniladas; 2) Investigações prévias indicando a viabilidade da decomposição térmica e a estabilidade relativa dos derivados bissulfenilados de tioésteres de diferentes estados de oxidação Ia-e, obtidos a partir do α-ceto-tioéster; 3) O estudo de síntese de precursores de α-ceto-tioésteres II e α-ceto-ésteres III, a saber: α - metilsulfonil- α - metiltio tioésteres IVa-c, -éster V e α, α - dimetiltio - ésteres VIa-c; 4) Decomposição térmica de α-metilsulfonil-α-metiltio-tioésteres Iva, b e c e -éster V sintetizados aos α-ceto-tioésteres e ésteres correspondentes, pelo emprego do método elaborado anteriormente por Wladislaw e col. e sugestão do mecanismo da mesma. A síntese de α metilsulfonil α metiltio tiopropionato de etila (Ivb), foi efetuada a partir do ácido α-cloro propiônico através de quatro passos reacionais, a saber: sulfenilação por substituição, oxidação à sulfona , tioesterificação e sulfenilação pelo emprego de NaH/MeS02SMe em DMSO. A obtenção do α - benzil - α - metilsulfonil - α - metiltio - tioacetato de etila (Ivc) foi efetuada a partir de ácido α-cloro acético através de reações de sulfenilação por substituição oxidação à sulfona tioesterificação alquilação com brometo de benzila e NaH em DMSO e, finalmente, a sulfenilação que só foi possível com o emprego de N-metiltioftalimida. A síntese de α-metilsulfonil-α-metiltio-propionato de etila (V) foi efetuada a partir do α-metilsulfonil malonato VIIa pelo eemprego do método de descarbetoxilação sulfenilativa usando 1,4 diazabiciclo [2,2,2] octano (DABCO) em tolueno sob refluxo e MeSO2SMe. Os compostos VIIa,b e c foram preparados a partir dos malonatos de dietila alquil - substituidos, seguido de sulfenilação e oxidação à sulfona. É de interesse a inédita reação de α - metilsulfonil fenilmalonato de dietila (VIIb), com DABCO em benzeno sob refluxo e MeSO2SMe, que conduziu à dessulfonilação sulfenilativa fornecendo o α - metiltio - fenilmalonato de dietila. É apresentada uma discussão mecanística tanto sobre descarbetoxilação, como sobre dessulfonilação sulfenilativas. A síntese de α,α-dimetiltio-ésteres VIa-c foi efetuada pela reação de sulfenilação com descarboxilação dos mono-ácidos malônicos correspondentes. O acompanhamento da descarboxilação e experimentos de deuteração permitiram esclarecer a sequência dos passos reacionais nestas novas reações. Cabe ressaltar que são compostos ainda não descritos na literatura os precursores IVa, IVb, IVc, V e Vib e 11 intermediários envolvidos nas reações efetuadas. Os resultados apresentados neste trabalho, além de importância sintética, trazem uma contribuição para a Química de Compostos Orgânicos de Enxofre.This work presents: 1) Two literature reviews, one about the synthesis of α-keto thioesters and esters and the other on the decomposition of sulfenylated sulfoxides and sulfones; 2) Previous investigations indicating the viability of thermal decomposition and the relative stability of the dithioderivatives of different oxidation states Ia-e,which were obtained from the α-keto thioester; 3) The study of synthesis of α-keto thioesters II and esters III precursors, which are the following: α-methylsulfonyl-α-methylthio-thioesters IVa-c and -ester V, and α, α - dimethylthio esters VIa-c; 4) Thermal decomposition of the synthesized α - methylsulfonyl- α -methylthio- thioesters Iva,b e c and ester V, to the corresponding α-keto thioesters and α-keto ester, through the method developed by Wladislaw et al., with the suggestion of the mechanism. α-Methylsulfonyl-α-methylthio ethyl thiopropionate (Ivb) was synthesized from α-chloro-propionic acid in four steps: sulfenylative substitution, oxidation to sulfone, thioesterification and sulfenylation using NaH/MeSO2SMe in DMSO. α-Benzyl-α-methylsulfonyl-α-methylthio ethyl thioacetate (,i>Ivc) was obtained from α-chloro acetic acid through the following steps: sulfenylative substitution, oxidation to sulfone, thioesterification, alkylation with benzylbromide and NaH in DMSO, and finally, the sulfenylation which was successful only with the use of N-methylthiophtalimide. α-Methylsulfonyl-α-methylthio ethyl propionate (V) was synthesized through the sulfenylative decarbethoxylation of α methylsulfonyl diethyl malonate VIIa employing DABCO (1,4-diazabicyclo [2.2.2.]octane), in refluxing toluene, and MeSO2Sme. The compounds VIIa,b e c were obtained by the alkylation of malonates, followed by sulfenylation and oxidation to sulfones. An interesting and novel reaction, the sulfenylative desulfonylation, was observed when α-methylsulfonyl phenyldiethyl malonate (VIIb) was treated with DABCO, in refluxing benzene and MeSO2SMe, which led to the α-methylthio diethyl malonate. A mechanistic discussion about the sulfenylative decarbethoxylation and sulfenylative desulfonylation is presented. α, α-dimethylthio esters VIa-c were synthesized by sulfenylation and decarboxylation of the corresponding malonic half-esters. The sequence of the steps of this new reaction could be determined by deuteration experiments and by following the evolution of CO2. The precursors IV, IVb, IVc, V e Vib and 11 intermediates were unknown compounds. This work, besides the synthetical importance, presents some contribution to the Organosulfur Chemistry.
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Paucard, Alexia. "Etude des mécanismes mis en jeu lors d'un stress oxydatif induit par l'injection intrastriatale de malonate chez le rat." Paris 5, 2003. http://www.theses.fr/2003PA05P643.
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L'existence d'un stress oxydatif (SO) a été rapportée dans diverses pathologies cérébrales. Dans ce contexte, notre travail a consisté à rechercher les mécanismes déclenchés par le SO ainsi que leur contribution à la mort neuronale. Le SO a été induit par l'injection de malonate (3 æmol), une toxine mitochondriale, dans le striatum de rats. Dans ce modèle, nous avons montré une chute précoce du glutathion total, le principal antioxydant endogène, associée à une lésion massive et à un œdème cérébral. L'a-phényl tert-butyl nitrone, un composé antioxydant, a exercé dans ce modèle un effet antiœdémateux. L'injection de malonate entraîne également une production de NO, par la NO-synthase neuronale. Ce NO module l'activation de la caspase 3, une des enzymes mises en jeu lors de la mort par apoptose. Cependant, l'inhibition de la caspase-3 n'a pas exercé d'effet neuroprotecteur. Le SO induit par le malonate déclenche donc des mécanismes conduisant principalement à une mort de type nécrotiqueOxidative stress (OS) has been reported in various cerebral pathogenesis. In this context, our work aimed to elucidate the mechanisms triggered by OS and their contribution to neuronal death. Our model of OS consisted in an injection of malonate (3 æmol), a mitochondrial toxin, in the striatum of rats. In this model, we showed an early drop of total glutathione, the major endogenous antioxidant, associated with a massive lesion and a cerebral edema. A-phenyl tert-butyl nitrone, an antioxidant compound, exerts in this model an antiedematous effect. Malonate injection was followed by NO production by the neuronal NO-synthase. This NO modulates caspase-3 activation, one of the enzymes implicated in apoptotic cell death. Nevertheless, inhibition of caspase-3 did not exert a neuroprotective effect. Thus the OS induced by malonate leads to neuronal death mainly through necrotic mechanisms
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Seitz, Thomas. "Synthèse rapide d’un delta-lactame modèle pour le radiomarquage au carbone-11 de la cytisine agoniste des récepteurs nicotiniques et Décarboxylation énantiosélective d’alpha-amino-hémi-malonates pour la préparation d’alpha amino-acides non-racémiques." Caen, 2006. http://www.theses.fr/2006CAEN2052.
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Le travail de thèse est divisé en deux parties indépendantes. La partie A concerne la synthèse rapide d’un lactame modèle pour le radiomarquage au carbone-11 de la cytisine, agoniste sélectif des récepteurs nicotiniques « nAChRs ». Compte tenu des précurseurs de carbone-11 disponibles et de la structure polyfonctionnelle de la cytisine nous avons envisagé une synthèse d’une molécule modèle de la cytisine utilisant le [11C]-phosgène. L’étape clef de la synthèse proposée est la formation d’un lactame par action d’un organométallique sur un chlorocarbamate. Le couplage intermoléculaire a été étudié et les organocuprates se sont révélés les meilleurs organométalliques pour ce couplage. Le couplage intramoléculaire pour la formation du lactame modèle a été étudiée dans trois conditions : (a) génération in situ d'un dianion et piégeage de celui-ci par le phosgène, (b) formation d'un lithien, piégeage de celui-ci par le phosgène puis cyclisation intramoléculaire via une débenzylation d'amine tertiaire et (c) réaction d'un vinyllithien sur la fonction chlorure de carbamoyle présente dans la molécule. Seule la dernière approche a donné des résultats satisfaisants, lorsque les réactions sont réalisées en milieu très dilué. Le lactame modèle a ainsi été obtenu avec un rendement allant jusqu'à 65%. La partie B décrit l'étude de la décarboxylation asymétrique d' hémimalonates, catalysée par une base chirale, dans le but de synthétiser des acides alpha-aminés cycliques, naturels ou non, énantioenrichis. Les résultats présentés par l'ensemble de cette étude permettent d'élargir le domaine d'application de cette méthodologie d'organocatalyse à la préparation d'esters de l'acide pipécolique avec des énantiosélectivités atteignant 72% sur plusieurs grammes de substrat. Les différents paramètres de la réaction contrôlant la sélectivité ont été définis. Ainsi, la faible polarité du solvant et le substituant aromatique sur l'azote du substrat sont les paramètres déterminants pour le substrat étudié. La température n'a qu'une influence sur la vitesse de la réaction mais pas sur l'énantiosélectivité. Un nombre important d'analogues des alcaloïdes du quinquina a été préparé. Une rationalisation des résultats a été proposée sur la base d'une étude de modélisation moléculaire de certains dérivés de la cinchonine, en particulier ceux donnant les meilleurs résultatsThe work of this thesis is divided into two independent parts. Part A reports the fast synthesis of a lactam as model compound of cytisine, a selective agonist of the nicotinic receptors "nAChRs", for radiolabelling with carbon-11. According to the available precursors in carbon-11 chemistry and the polyfunctional structure of cytisine we design a synthesis of a model compound of cytisine using [11 C]-phosgene. The key reaction of the synthesis is the formation of a lactam by the reaction of an organometallic species onto a carbamoyle chloride group. The intermolecular coupling was studied and organocuprates appeared as the best organometallic reagents for this coupling. The intramolecular coupling for the formation of the lactam model was studied under three conditions: (A) in situ generation of a dianion and trapping it with phosgene, (b) formation of a lithiated anion and then trapping it with phosgene followed by cyclization via debenzylation of tertiary amine and (c) reaction of a vinyl lithium on carbamoyle chloride. Only the last approach gave satisfactory results, when the reactions are carried out under diluted conditions. This cyclization yielded the lactam with a yield up to 65 %. The part B describes the study of the asymmetric decarboxylation of hemimalonates, catalysed by a chiral base, with the aim of synthesizing enantiopur alpha- amino cyclic acids. The results of this study extend the scope of this methodology to the preparation of pipecolic acid ester with enantioselectivities reaching 72 % on a several grams scale. The parameters of the reaction controlling the selectivity were determined. The low polarity of the solvent and the aromatic substituent on nitrogen of the substrate were the key parameters to achieve the highest selectivities. The temperature influenced only the rate of the reaction without affecting the enantioselectivity. A number of analogues of cinchona alkaloids were prepared. A rationalization of the results was proposed based on a molecular modeling study of the organocatalysts in particular of those giving the best results derived from cinchonine
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CANET, JEAN-LOUIS. "Construction asymetrique de carbones quaternaires a partir de malonates prochiraux : applicatio a la synthese selective des enantiomeres des alpha- et beta-cuparenones et de l'epilaurene. determination des exces enantiomeriques a l'aide de la rmn#2h en milieu cristal liquide cholesterique." Paris 11, 1992. http://www.theses.fr/1992PA112192.
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Le travail rapporte dans ce memoire de these concerne la preparation d'un synthon quaternaire chiral de haute purete enantiomerique et son application a la synthese totale de produits naturels cyclopentaniques. Dans la premiere partie est tout d'abord exposee, par hydrolyse enzymatique enantioselective d'un malonate prochiral, la preparation d'un synthon chiral que nous avons choisi pour conduite selectivement aux enantiomeres des alpha- et beta-cuparenones. Les reductions chimioselectives anormales des fonctions acide et ester de ce chiron, l'acide (r)-(+)-2-methoxycarbonyl-2-(4-methylphenyl) propanoique, sont decrites et le mecanisme interprete. Ces reductions ont permis les syntheses regioselectives des precurseurs directs des enantiomeres des beta- et alpha-cuparenones via, respectivement, un succinate de methyle (cyanation), un butanolide (diazotation un butenolide non conjugue (elimination) et un lactol a cinq chainons (reaction de wittig). Tous ces composes, ainsi que leurs intermediaires, comportent un carbone quaternaire de haute purete enantiomerique (superieure a 98% ee). Dans la seconde partie est decrite la premiere synthese enantioselective de l'epilaurene a partir de ce meme synthon chiral. La double homologation par reactions de wittig du premier intermediaire cle a pu etre amelioree par sonochimie; et le meme mecanisme de ces reactions precise. La purete enantiomerique (98% ee) des composes obtenus lors de cette synthese a ete determinee, et ce pour la premiere fois, par rmn du deuterium en milieu cristal liquide cholesterique lyotrope
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Meldrum, Alicia. "Malonate-induced toxicity in the striatum." Thesis, University of Cambridge, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.624552.
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Goodall, Mark John. "Enantioselective decarboxylativeprotonation of malonic acids using aryl malonate decarboxylase." Thesis, University of Manchester, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.564336.
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The demand for new methods through which important enantiopure compounds can be produced is increasing within the chemical industry. In this regard, one group of interesting compounds are enantiopure carboxylic acids as traditional methods towards producing these compounds that rely on a process known as enantioselective decarboxylative protonation (EDP) are often insufficient due to a combination of factors including low yields, low enantioselectivities, the need for environmentally deleterious reaction conditions and high costs. Due to the shortcomings of these synthetic techniques, the application of biological systems is an alternative method that has come to the forefront of current research, which is because biological systems often boast a number of advantages over traditional chemical methods. Described within this thesis is one such biological method towards the production of enantiopure carboxylic acid compounds via EDP, a method that utilises the enzyme aryl malonate decarboxylase (AMDase). This research follows on from previous work detailing the mechanism this enzyme utilises toperform decarboxylation reactions and specifically looks into the substrate specificity that thisenzyme possesses. This work allows us to see how flexible this method is with regards to theproduction of a range of different carboxylic acid products, which is important as previous chemical methods are often limited by a lack of diversity. It also allows us to see how the kinetic parameters of the enzyme catalysed reactions change dependent on the identity of the substrate, allowing us to better justify the currently proposed mechanism and to better direct attempts to improve the enzyme through mutagenesis experiments. Indeed, several mutagenesis experiments have also been performed in an attempt to producevariants of the enzyme that would have either an increased enzyme scope or better reactivity with currently known substrates, and this work is also detailed within this thesis.
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Puntel, Robson Luiz. "Efeito de intermediários do ciclo de krebs sobre alterações oxidativas induzidas por diferentes agentes oxidantes." Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/11136.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorRecent data from the literature have suggested that some Krebs cycle intermediates could act as potent antioxidant agents, both in vitro and in vivo, against a variety of pro-oxidant agents. However, the mechanism(s) involved in the antioxidant effect of Krebs cycle intermediates are not fully understood. Additionally, there are scarce data in the literature taking into account the in vitro effect of Krebs cycle intermediates during oxidative stress conditions. Thus, the aim of this study was to determine the effect of some Krebs cycle intermediates on lipid peroxidation induced in vitro by different pro-oxidant agents, and the mechanism(s) by which they act. Firstly, we investigated the effect and the mechanism(s) by which malonate and quinolinic acid modulate the thiobarbituric acid- reactive species (TBARS) production in vitro, using rat brain S1 preparations (Article 1). The present results showed that the malonate-induced TBARS production was not changed by potassium cyanide or MK-801. However, the pro-oxidant effect of quinolinic acid was significantly prevented by MK-801. In addition we found that malonate was able to form complexes with iron ions (Fe2+), but these complexes were not able to interfere with in vitro deoxyribose degradation assays. Based on the results presented, we conclude that malonate pro-oxidant activity in vitro seems to be independent of the NMDA receptors activity. Additionally, we suggest that the malonate effect, in these conditions, is due to its ability to form complexes with iron ions, thus modulating an adequate ratio Fe2+/Fe3+ that could cause an increase in free radicals generation. In contrast, the quinolinic acid effect seems to be dependent of the NMDA receptors activation. However, we can not rule out the involvement of iron ions in quinolinic acid toxicity under our assay conditions. An other objective of this study was to investigate the effect of some Krebs cycle intermediates on quinolinic acid- or iron (Fe2+)-induced TBARS production in the rat brain S1 preparations, and the mechanism(s) by which they act (Article 2). The results showed that oxaloacetate, citrate, succinate, and malate were able to significantly prevent both basal and quinolinic acid- or iron-induced TBARS production. However, α-ketoglutarate induced per se a significant increase in basal TBARS production. The addition of potassium cyanide or the heat-treatment of S1 at 100ºC during 10 min completely abolished the antioxidant succinate activity, without change the effect of other Krebs cycle intermediates studied. Except for succinate, all intermediates used in this study were able to form complexes with iron (Fe2+) ions, however only oxaloacetate and α-ketoglutarate significantly prevented deoxyribose degradation induced by hydrogen peroxide. Based on the results presented, we concluded that oxaloacetate, malate, succinate, and citrate could act as antioxidants under basal, and under quinolinic acid- or iron- induced TBARS production, whereas α-ketoglutarate act as a pro-oxidant agent per se. The mechanism(s) by which citrate, malate, and oxaloacetate acts seems to be related to their ability to form complexes with iron (Fe2+) ions, thus modulating the iron redox cycle. In contrast, the succinate antioxidant effect seems to be dependent of the succinate dehydrogenase (SDH) activity.
Dados recentes na literatura têm relatado que alguns intermediários do ciclo de Krebs podem agir como potentes antioxidantes, tanto in vitro, quanto in vivo, em diversos sistemas pró-oxidantes. Porém, o(s) mecanismo(s) através dos qual(is) os intermediários do ciclo de Krebs exercem suas atividades antioxidantes não são completamente entendidas. Considerando a escassez de dados in vitro na literatura a respeito do efeito desses intermediários durante situações de estresse oxidativo, o presente trabalho tem como objetivo determinar o efeito de intermediários do ciclo de Krebs sob a peroxidação lipídica induzida por diferentes agentes pró-oxidantes in vitro, bem como investigar o(s) mecanismo(s) de ação dos mesmos. Primeiramente investigamos o efeito e o(s) mecanismo(s) pelo(s) qual(is) o malonato e o ácido quinolínico modulam a produção de espécies reativas ao ácido tiobarbitúrico (TBARS) em S1 de cérebro de ratos, in vitro (artigo 1). Os resultados obtidos mostraram um aumento na produção de TBARS induzido pelo malonato, o qual não foi modificado pela adição de cianeto de potássio, nem pelo MK-801. Por outro lado, o efeito pró-oxidante do ácido quinolínico foi significativamente prevenido pelo MK-801. Observamos ainda que o malonato foi capaz de formar complexos com íons ferrosos e que esses complexos não foram capazes de interferir nos ensaios da degradação da desoxirribose in vitro. Portanto, com base nos resultados encontrados, concluímos que o efeito pró-oxidante do malonato in vitro parece ser independente da atividade dos receptores NMDA. Os resultados sugerem que o efeito do malonato nessas condições deve-se principalmente a sua capacidade de interagir com íons ferro, modulando uma razão Fe2+/Fe3+ que favorece a geração de radicais livres. Por outro lado, o efeito do ácido quinolínico parece ser devido à ativação dos receptores NMDA. Porém, não podemos excluir a participação dos íons ferro para a toxicidade do mesmo nessas condições. Outro foco deste estudo foi investigar o efeito de alguns intermediários do ciclo de Krebs na produção de TBARS induzida por ácido quinolínico ou ferro em S1 de cérebro de ratos in vitro, bem como investigar o(s) mecanismo(s) de ação dos mesmos (artigo 2). Os resultados mostraram que o oxaloacetato, o citrato, o sucinato e o malato foram capazes de reduzir significativamente a produção de TBARS basal, bem como a induzida por ácido quinolínico ou ferro. Por outro lado, o α-cetoglutarato foi capaz de induzir per se um significativo aumento na produção de TBARS. A adição de cianeto de potássio, bem como o pré-tratamento do S1 por 10 min a 100ºC aboliram completamente o efeito antioxidante do sucinato, sem interferir significativamente no efeito dos demais intermediários estudados. Todos os intermediários estudados, exceto o sucinato, foram capazes de quelar íons ferro, porém somente o oxaloacetato e o α-cetoglutarato foram capazes de prevenir a degradação da desoxirribose induzida por peróxido de hidrogênio. Com base nos resultados obtidos, podemos concluir que o oxaloacetato, o malato o sucinato e o citrato agem como antioxidantes sob condições basais ou em presença do ácido quinolínico ou ferro, enquanto que o α-cetoglutarato age como um agente pró-oxidante per se. O mecanismo pelo qual o citrato, o malato e o oxaloacetato exercem seus efeitos antioxidantes parece ser devido à capacidade desses em interagir com íons ferro modulando o ciclo redox desse. Por outro lado, o efeito do sucinato parece ser devido à atividade da enzima succinato desidrogenase (SDH).
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Bouhlel, Ahlem. "Cyclisations radicalaires oxydatives médiées par l'acétate de manganèse (III) et orientées vers la chimie médicinale." Electronic Thesis or Diss., Aix-Marseille, 2012. http://www.theses.fr/2012AIXM5501.
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Ce travail s'inscrit dans la recherche et le développement de nouvelles molécules à visée thérapeutique via la mise au point de cyclisations radicalaires oxydatives médiées par l'acétate de manganèse(III). Deux problématiques ont dirigé nos recherches. Tout d'abord, nous avons développé une stratégie de synthèse de prodrogues analogues de la pafuramidine, molécule antileishmanienne. Ainsi, une 1ère série d'amidoximes a été obtenue à partir de β-cétosulfones par une synthèse multi-étapes faisant appel aux réactions i) de cyclisations radicalaires oxydatives médiées par Mn(OAc)3 et ii) de couplages pallado-catalysées de Buchwald-Hartwig et de Heck. Suite à l'évaluation biologique in vitro sur Leishmania donovani et sur des cellules humaines, une 2ème série d'amidoximes et en particulier des monoamidoximes a été réalisée, ce qui a révélé une molécule présentant un index de sélectivité 40 fois plus élevé que celui de la pentamidine, médicament utilisé comme référence. Nous avons également mis au point un double couplage "one-pot" de Buchwald-Hartwig dans le but d'obtenir des produits dicouplés dissymétriques, précurseurs éventuels de futures diamidoximes. Dans une deuxième partie, nous nous sommes focalisés sur la synthèse de composés spirocycliques pouvant constituer un pharmacophore original. De ce fait, une stratégie de synthèse conduisant à divers noyaux tels des tétralines spirocycliques, des spirolactones, des spirobenzophénanthrédin-6(5H)-ones a été mise au point. Ce travail nous a également menés vers la synthèse de dérivés thiobarbiturates, analogues de composés anesthésiques ou anticonvulsivantsThis work focuses on the research and development of new therapeutic molecules through optimized radical cyclizations mediated by manganese(III) acetate. Two problematics directed our research. First, we developed analogous prodrugs of pafuramidine, an antileishmanial molecule. Thus, a 1rst series of amidoximes was obtained from β-ketosulfones by a multi-step synthesis involving i) radical oxidative cyclizations mediated by Mn(OAc)3 and ii) pallado-catalyzed Buchwald-Hartwig and Heck coupling reactions. The 1rst series being biologically evaluated in vitro, both on Leishmania donovani and human cells, a 2nd series and particularly monoamidoximes was prepared and revealed a molecule presenting a selectivity index 40 times higher than the one of pentamidine, used as reference drug compound. We also developed a one-pot double Buchwald-Hartwig coupling reaction in the aim to obtain dissymmetric dicoupled products, potential precursors of future diamidoximes. In a second time, we focused on the synthesis of spirocyclic compounds which could constitute an original pharmacophore. Therefore, we performed a synthesis allowing access to a wide variety of scaffolds such as spirocyclic tetralins, spirolactones, spirobenzophenanthridin-6(5H)-ones. This work allowed the synthesis of thiobarbiturates, analogous of anesthetic or anticonvulsive compounds
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Puntel, Robson Luiz. "Caracterização da atividade pró-oxidante de diferentes agentes e estudo do potencial antioxidante de intermediários do ciclo de krebs sobre alterações oxidativas induzidas in vitro." Universidade Federal de Santa Maria, 2008. http://repositorio.ufsm.br/handle/1/4400.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorPrevious data from the literature have shown that some Krebs cycle intermediates could act as antioxidant in several models, both in vitro and in vivo. However, the mechanism(s) involved in the antioxidant effect of Krebs cycle intermediates are not fully understood. Additionally, there are scarce data in the literature taking into account the in vitro effect of Krebs cycle intermediates during oxidative stress conditions. Thus, the aim of this study was to determine the effect of some Krebs cycle intermediates on lipid peroxidation induced in vitro by different pro-oxidant agents, and the mechanism(s) by which they act. Furthermore, it was necessary elucidate the mechanisms by which the different pro-oxidants acts under in vitro conditions. The present results showed that the malonate-induced TBARS production was not changed by potassium cyanide or MK-801. However, the pro-oxidant effect of quinolinic acid was significantly prevented by MK-801. In addition we found that both malonate and oxalate were able to form complexes with iron ions (Fe2+). Based on the presented results, we conclude that malonate pro-oxidant activity in vitro seems to be independent of the secondary excitotoxicity via indirect NMDA receptors activation. Additionally, we suggest that both the malonate and oxalate effect, in these experimental conditions, is due to its ability to form complexes with iron ions, thus modulating an adequate ratio Fe2+/Fe3+ that could cause an increase in free radicals generation. In contrast, the quinolinic acid effect seems to be dependent of the NMDA receptors activation. However, we can not rule out the involvement of iron ions in quinolinic acid toxicity under our assay conditions. Another objective of this study was to investigate the effect of some Krebs cycle intermediates against either basal or induced TBARS production, using rat brain S1 preparations and the mechanism(s) by which they act. The results showed that oxaloacetate, citrate, succinate, and malate were able to significantly prevent both basal and quinolinic acid-, iron- or malonate-induced TBARS production. On the other hand, fumarate prevented only malonate-induced TBARS production, without effect under basal conditions. However, α-ketoglutarate induced per se a significant increase in basal TBARS production. The antioxidant activity of fumarate and succinate were completely abolished when S1 was submitted to heat-treatment at 100ºC during 10 min. Likewise, potassium cyanide completely abolished the antioxidant effect of succinate. The effect of other Krebs cycle intermediates studied was unchanged with respect to heat-treatment, or cyanide. Except for succinate and fumarate, all intermediates used in this study were able to form complexes with iron (Fe2+) ions, however only oxaloacetate and α-ketoglutarate significantly prevented deoxyribose degradation induced by hydrogen peroxide. Based on the results presented, we concluded that oxaloacetate, malate, succinate, fumarate and citrate could act as antioxidants under such conditions, whereas α-ketoglutarate acts as a pro-oxidant agent per se. The mechanism(s) by which citrate, malate, and oxaloacetate acts seems to be related to their ability to form complexes with iron (Fe2+) ions, thus modulating the iron redox cycle. In contrast, the succinate and fumarate antioxidant effect seems to be dependent of the some enzymatic system.
Dados prévios da literatura têm mostrado que alguns intermediários do ciclo de Krebs podem agir como antioxidantes em diversos modelos, tanto in vitro, quanto in vivo. Porém, o(s) mecanismo(s) através dos qual(is) esses intermediários exercem suas atividades antioxidantes não são completamente entendidas. Considerando a escassez de dados na literatura a respeito do efeito dos intermediários do ciclo de Krebs durante situações de estresse oxidativo, o presente trabalho teve por objetivo determinar o efeito desses sob a peroxidação lipídica induzida por diferentes agentes pró-oxidantes in vitro, bem como investigar o(s) mecanismo(s) de ação dos mesmos. Além disso, faz-se necessário caracterizar o(s) mecanismos(s) pelo(s) qual(is) os diferentes pró-oxidantes agem nos sistemas in vitro. Os resultados dessa tese mostraram que a atividade pró-oxidante in vitro do malonato não foi modificada pela adição de cianeto de potássio, nem pelo MK-801. Por outro lado, o efeito pró-oxidante do ácido quinolínico foi significativamente prevenido pelo MK-801. Observamos ainda que o malonato, e também o oxalato foram capazes de formar complexos com íons ferrosos. Portanto, com base nos resultados encontrados, concluímos que o efeito pró-oxidante do malonato in vitro parece ser independente da excitotoxicidade secundária, conseqüência da ativação indireta dos receptores NMDA. Os resultados sugerem que o efeito do malonato e do oxalato nessas condições experimentais deve-se principalmente a sua capacidade de interagir com íons ferro, modulando uma razão Fe2+/Fe3+ que favorece a geração de radicais livres. Por outro lado, o efeito do ácido quinolínico parece ser devido à ativação dos receptores NMDA. Porém, não podemos excluir a participação dos íons ferro para a toxicidade do mesmo nessas condições. Outro foco deste estudo foi investigar o efeito de alguns intermediários do ciclo de Krebs na produção de TBARS basal ou induzida por diferentes pró-oxidantes em S1 de cérebro de ratos in vitro, bem como investigar o(s) mecanismo(s) de ação dos mesmos. Os resultados mostraram que o oxaloacetato, o citrato, o sucinato e o malato foram capazes de reduzir significativamente a produção de TBARS basal, bem como a induzida por ácido quinolínico, ferro ou malonato. O fumarato, por sua vez, teve efeito antioxidante somente sobre a produção de TBARS induzida. Por outro lado, o α-cetoglutarato foi capaz de induzir per se um significativo aumento na produção de TBARS. O efeito antioxidante do fumarato e do sucinato foi completamente abolido quando o S1 foi submetido a um prétratamento por 10 min a 100ºC, enquanto que o efeito dos demais intermediários permaneceu inalterado. Da mesma forma, a adição de cianeto de potássio aboliu completamente o efeito antioxidante do sucinato sem interferir significativamente no efeito dos demais intermediários estudados. Todos os intermediários estudados, exceto o sucinato e o fumarato, foram capazes de quelar íons ferro, porém somente o oxaloacetato e o α- cetoglutarato foram capazes de prevenir a degradação da desoxirribose induzida por peróxido de hidrogênio. Com base nos resultados obtidos, podemos concluir que o oxaloacetato, o malato, o sucinato, o fumarato e o citrato agem como antioxidantes sob determinadas condições, enquanto que o α-cetoglutarato age como um agente pró-oxidante per se. O mecanismo pelo qual o citrato, o malato e o oxaloacetato exercem seus efeitos antioxidantes parece ser devido à capacidade desses em interagir com íons ferro modulando o ciclo redox desse. Por outro lado, o efeito do sucinato e do fumarato parece ser devido a alguma atividade enzimática.
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Deshayes, Natacha. "Synthèse et caractérisation de copolymères cationiques à base d'un méthylidène malonate de monomères aminés." Mulhouse, 2003. http://www.theses.fr/2003MULH0739.
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Le présent travail a consisté à mettre au point une nouvelle gamme de vecteurs cationiques pour véhiculer des entités polyanioniques comme l'ADN. Pour cela deux types de monomères ont été sélectionné : le MM 2. 1. 2 (1-ethoxycarbonylméthylèneoxycarbonyl éthène), qui apporterait le caractère bioérodable et un monomère aminé, qui permettrait la complexation avec l'ADN. Le vecteur synthétique choisi est un copolymère cationique obtenu par copolymérisation radicalaire en solution de ces deux monomères. La première partie de ce manuscrit a été consacrée à la synthèse des monomères cationiques ayant des groupements espaceurs de type chaîne alkyle, acide aminé ou oxyde d'éthylène. Des tests in vitro nous ont permis de sélectionner le monomère cationique le plus adapté à notre application : le méthacrylate de 2-aminoéthyle (AEMA). Dans une deuxième partie, des études cinétiques très détaillées, effectuées par RMN 1H in situ, en fonction de la concentration en amorceur et en monomère, ont permis de déterminer les vitesses de polymérisation (vp), ainsi que les principales constantes cinétiques (kp/kt0,5) pour le MM 2. 1. 2 et le BocAEMA (forme protégée du AEMA). L'influence de la viscosité de la solution de polymère sur ce rapport a été mise en évidence. Il a notamment été remarqué que le BocAEMA est plus réactif que le MM 2. 1. 2. Nous avons ensuite étudié la copolymérisation du MM 2. 1. 2 avec le méthacrylate de méthyle (MMA) et le BocAEMA. Les paramètres de réactivité (r1, r2) et ceux d'Alfrey-Price (e, Q) ont alors été déterminés pour ces monomères. Les copolymères synthétisés sont de type statistique et ils ont une composition azéotropique à environ 40 % molaire en MM 2. 1. 2. Enfin, nous avons formulés les copolymères cationiques poly(méthylidène malonate 2. 1. 2)-stat-(méthacrylate de 2-aminoéthyle). D'une part, les copolymères hydrosolubles ont permis la synthèse de complexe cationique par mélange direct avec l'ADN. Et d'autre part, les copolymères hydrophobes ont été formulés par la méthode de coacervation sous forme de nanoparticules avec des tailles reproductibles et monodisperses allant de 100 à 300 nm. Ces tailles sont intéressantes pour des applications intraveineuses. La viscosité de la solution dispersée est apparue comme étant le paramètre le plus important pour les synthèses de ce type. Le taux de fonctions amines en surface a été évalué par deux techniques : la RMN 1H et la conductimétrie. 70 à 60% de fonctions amines sont présentes en surface pour des tailles allant de 150 à 200 nm. L'utilisation de copolymère bloc PMM 2. 1. 2-b-POE a permis de synthétiser des nanoparticules cationiques dites furtives ayant un temps de circulation plus important dans l'organismeThe present work consisted in developing a new range of cationic vectors to carry anionic drugs like DNA. For that two types of monomers were selected : le methylidene malonate 2. 1. 2, which would bring the bioerodable character and a monomer containing amino group which would allow the complexation with the DNA. The selected synthetic vector is a cationic copolymer obtained by free radical copolymerization in solution of these two monomers. The first part of this manuscript was devoted to the synthesis of the cationic monomers having different spacers (alkyl, acid amino or ethylene oxide). In vitro tests enabled us to select the cationic monomer more adapted to our application: the 2-aminoethylmethacrylate (AEMA). In a second part, very detailed kinetic studies, carried out by NMR 1H " in situ ", as a function of the initiator and monomer concentration, made it possible to determine rate speeds of polymerization (Rp), as well as the main kinetic constants (kp/kt0,5) for the MM 2. 1. 2 and BocAEMA (protected form of the AEMA). The influence of the viscosity of the polymer solution on this ratio was highlighted. It was in particular noticed that BocAEMA is more reactive than the MM 2. 1. 2. We then studied the copolymerization of the MM 2. 1. 2 with methylmethacrylate (MMA) and BocAEMA. The reactivity parameters (r1, r2) and those of Alfrey-Price (e, Q) were then determined for these monomers. The synthesized copolymers are statistical and they have an azeotropic composition at approximately 40 % molar in MM 2. 1. 2. Lastly, we formulated cationic copolymers poly(methylidene malonate 2. 1. 2)-stat-(2-aminoethylmethacrylate). On the one hand, the water-soluble copolymers allowed the synthesis of cationic complexes by direct mixing with the DNA. And in addition, the hydrophobic copolymers were formulated by the method of coacervation in the form of nanoparticules with reproducible and monodisperse sizes from 100 to 300 nm. These sizes are interesting for intravenous applications. The viscosity of the dispersed solution seemed being the most important parameter on the size of the particles. The amount of amine functions on the surface was evaluated by two techniques : NMR 1H and conductimetry. 70 to 60 % of amine functions are present on the surface for sizes from 150 to 200 nm. The use of PMM 2. 1. 2-b-POE block copolymer made it possible to synthesize cationic nanoparticles, known as stealth particle, having then a more important circulation time in blood
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Libório, M. N. "Estudo termodinâmico e espectroscópico de sistemas líquidos binários contendo (dietil malonato + álcoois) a diferentes temperaturas e pressão atmosférica/." reponame:Biblioteca Digital de Teses e Dissertações da FEI, 2015. http://sofia.fei.edu.br:8080/pergamumweb/vinculos/00000d/00000def.pdf.
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Hilbi, Hubert Franz Pius Hilbi Hubert Franz Pius Hilbi Hubert Franz Pius Hilbi Hubert Franz Pius. "The malonate decarboxylase enzyme system of Malonomonas rubra : identification, purification and biochemical characterization of components /." [S.l.] : [s.n.], 1994. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10766.
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Beliard, Isabelle. "Synthèse et propriétés de matériaux à base de polyméthylidène malonate sous formes particulaire et filmogène." Besançon, 1998. http://www.theses.fr/1998BESA2083.
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Les travaux réalisés ont été axés autour des formulations et des propriétés physico-chimiques d'un biomatériau acrylique. Des nanoparticules de ce matériau ont pu être synthétisées par coacervation. Les conditions opératoires optimisées ont. été étudiées via l'élaboration de diagrammes ternaires. ,La synthèse de microsphères par émulsions multiples E/H/E a été mise en oeuvre. Des études de stabilité de l'émulsion interne, corrélées à des observations par cryofracture et par Microscopie Confocale, ont été effectuées pour définir les conditions opératoires optimales associées à ce mode de synthèse. Le caractère hydrophobe de ce matériau est à la base d'interactions interfaciales pénalisantes entre ce polymère et les biomolécules encapsulées. Pour caractériser ce phénomène, il a été utilisé les propriétés filmogènes du polymère afin de réaliser des mesures d'angle de contact permettant le calcul de l'énergie interfaciale de ce solide. Il a été montré que les composantes de l'énergie de surface caractéristiques de l'adsorption de biomolécules varient lorsque le polymère est mis en présence de biomolécules en milieu aqueux. Un suivi cinétique de l'évolution de l'angle de contact d'une goutte de solution aqueuse de biomolécules déposée sur un film de polymère a été effectué pour suivre l'évolution temporelle de l'adsorption. Pour minimiser les phénomènes interfaciaux des synthèses par spray-coating ont été mises en œuvre. Des essais de faisabilité portant sur l'utilisation de ce matériau sous forme de colle synthétique ont été envisagés.
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Marques, Marcelo Volpatto. "Preparação de y, -epóxi malonatos e aplicação na síntese de ciclopropano carboxamidas e y-arilmetil lactonas." reponame:Repositório Institucional da UFSC, 2014. https://repositorio.ufsc.br/xmlui/handle/123456789/128898.
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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2014.Made available in DSpace on 2015-02-05T20:28:02Z (GMT). No. of bitstreams: 1 327834.pdf: 7274767 bytes, checksum: b8990c375238916dc970ba08073c23bc (MD5) Previous issue date: 2014
Neste trabalho foram desenvolvidos métodos simples e eficientes para a síntese estereosseletiva de ciclopropanos multifuncionalizados e ?-arilmetil lactonas, em ambos os casos, a partir de ?,?-epóxi malonatos. Estes epóxidos foram preparados pela epoxidação quimiosseletiva de malonatos alilados utilizando Oxone em um sistema bifásico sob condições básicas tamponadas, sendo isolados com rendimentos de 72 a 85%. Os ?,?-epóxi malonatos obtidos foram, então, utilizados para a síntese estereosseletiva de novos ciclopropanos multifuncionalizados por meio da reação com aminas, promovida por LiCl e sob condições suaves. Esta transformação do tipo dominó envolve inicialmente a ciclopropanação intramolecular via abertura do anel do epóxido a partir do enolato gerado na presença de uma base de Brønsted (amina) e catalisado pelo LiCl. As etapas subsequentes consistem de lactonização e aminólise do anel da lactona gerando as ciclopropano carboxamidas, as quais foram isoladas em bons rendimentos. Este método fornece elevada economia atômica, é extremamente modular, operacionalmente simples e tolera uma variedade de grupos funcionais. O uso de materiais facilmente disponíveis e a utilização de um solvente sustentável (metanol ou etanol) à temperatura ambiente tornam este processo dominó altamente eficaz. A reatividade destes epóxidos foi também testada para preparação de ?-arilmetil lactonas de interesse farmacológico. Na primeira etapa da síntese, a hidrogenólise regiosseletiva dos ?,?-epóxi malonatos arilados catalisada por paládio, em THF, levou à formação dos respectivos ?-hidróxi malonatos sob condições brandas, em meio neutro e à temperatura ambiente em excelentes rendimentos. A segunda etapa envolve um método one-pot, assistido por micro-ondas, de lactonização seguida por descarboxilação dos ?-hidróxi malonatos para fornecer as ?-arilmetil lactonas com diferentes padrões de substituição no anel aromático. Algumas ?-arilmetil lactonas metóxi substituídas, as quais foram preparadas por esta metodologia de três etapas a partir de malonatos alilados em bons redimentos globais (42 a 59%), são de particular interesse devido a sua ocorrência como metabólitos da catequina, um produto natural encontrado no chá verde.
Abstract : This work presents simple and efficient methods for the stereoselective synthesis of multifunctionalized cyclopropanes as well as ?-arylmethyl lactones from ?,?-epoxy malonates. The preparation of ?,?-epoxy malonates was achieved by a chemoselective epoxidation of allylated malonates using Oxone in a two-phase system under buffered basic conditions to give the expected epoxides in high isolated yields (72-85%). The ?,?-epoxy malonates were then treated with LiCl and a variety of amines under mild conditions for the stereoselective synthesis of novel cyclopropane carboxamides. This domino process involves the initial cyclopropanation via intramolecular ring-opening of ?,?-epoxy malonates through the cooperative catalysis of LiCl (acting as a Lewis acid) and a Brønsted base (a primary or, in selected cases, a secondary amine). The sequential events consisted of lactonization and aminolysis of the lactone ring that ultimately furnished cyclopropane carboxamides with different substitution patterns in good isolated yields (60-80%). This method proceeds with high atom economy, is remarkably modular, operationally simple and tolerates a variety of functional groups. The involvement of readily available starting materials, the broad scope, and the use of a sustainable solvent (methanol or ethanol) at ambient temperature make this domino process highly effective. The reactivity of the ?,?-epoxy malonates was also investigated with the aim of obtaining ?-arylmethyl lactones of pharmacological interest. In the first step of the synthesis, the palladium-catalyzed regioselective hydrogenolysis of ?-arylated ?,?-epoxy malonates in THF led to the formation of the corresponding ?-hydroxy malonates in excellent yields under neutral conditions at room temperature. The second step involved a microwave-assisted one-pot lactonization of the ?-hydroxy malonates followed by decarboxylation to furnish ?-arylmethyl lactones and analogues with different substitution patterns in the aromatic ring. Some methoxy-substituted ?-arylmethyl lactones, which were prepared by this three-step methodology from the allylated malonates in good overall yields, are of particular interest due to their occurrence as metabolites of catechin, a natural product found in green tea.
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Li, Zhenxuan. "Étude de la sorption du cadmium et du malonate sur la calcite : effets synergiques en système ternaire." Thesis, Lille 1, 2010. http://www.theses.fr/2010LIL10104.
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La sorption du cadmium sur la calcite est étudiée en système ternaire, en présence, simultanément d’un ligand organique (malonate) et du cadmium. D’abord nous avons étudié l’interaction entre le malonate et la calcite. L’influence du malonate sur la solubilité de la calcite, le signal du malonate en spectroscopie infrarouge et enfin la modélisation des isothermes d’adsorption par un modèle de complexation de surface à trois plans (CD-MUSIC) nous ont permis de proposer un modèle pour la spéciation du malonate à la surface de la calcite et d’estimer quantitativement l’adsorption. Ensuite, nous avons étudié la sorption du cadmium sur la calcite, respectivement en absence et en présence de malonate. En absence de malonate, l’adsorption du cadmium donne lieu à une isotherme classique, de valeurs connues. La modélisation néanmoins révèle quelques difficultés de paramètrage. L’étude de la sorption en réacteur à écoulement continu sous conditions proches de l’équilibre CaCO3-H2O-CO2 met en évidence une parfaite réversibilité adsorption/désorption du cadmium. Notons que aucune expérience de sorption ne dépassait une durée totale de 60 heures. En présence de malonate, expériences et modélisations indiquent un effet négatif du malonate sur la sorption du cadmium. La cinétique de sorption est notablement ralentie et le cadmium est, en partie, fixé plus fortement à la surface. Les résultats tendent à montrer que la présence de malonate ralentit considérablement l’atteinte d’un équilibre de sorption du cadmium sur la calciteThe sorption of cadmium by calcite was studied in a ternary system, with an organic ligand (malonate) and cadmium simultaneously present in solution. First we studied the interaction between malonate and calcite. The influence of malonate on the solubility of calcite, malonate spectra in infrared spectroscopy, and the modelling of isotherms by a 3-plane surface complexation model (CD-MUSIC) allowed us to propose a model for the speciation of malonate at the surface of calcite and to estimate adsorption quantitatively. In a second step, we have studied the sorption of cadmium by calcite, without and with malonate respectively. When malonate was not present, cadmium sorption by calcite gave rise to an isotherm with known values. Modelling however revealed some difficulties with parametrisation. Studying sorption under continuous flow in a “Stirred Flow Through Reactor” under conditions close to CaCO3-H2O-CO2 equilibrium, showed perfectly reversible adsorption/desorption of cadmium. Note that sorption experiments were conducted over 15 to 60 hours at maximum. When malonate was present, experiments and modelling indicated that malonate reduced the sorption of cadmium. Sorption kinetics were significantly lower and cadmium, in part, sorbed more strongly on the calcite surface. The results tend to show that the presence of malonate slows down the reach of sorption equilibrium of cadmium with calcite
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Suisse, Philippe. "Synthèse du malonate de dimethyle par méthoxycarbonylation du dichlorométhane en catalyse homogène : méthodes chimiques et électrochimiques." Lille 1, 1994. http://www.theses.fr/1994LIL10156.
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La methoxycarbonylation du dichloromethane en malonate de dimethyle a ete effectuee en presence d'ions methanolates sous pression de monoxyde de carbone et a l'aide d'un catalyseur a base de cobaltco(co)#3pbu#3#2. Utilise directement sous cette forme, il entraine des conversions en reactifs faibles et un rendement en malonate de dimethyle de 15% comparable a ceux obtenus dans la litterature. La reduction chimique prealable du catalyseur en cobaltate correspondant co(co)#3pbu#3#-, veritable espece active, sur amalgame na(hg) permet de diminuer le temps reactionnel de presque 20 heures mais n'ameliore pas le resultat final. Seule la reduction par voie electrochimique du catalyseur en presence d'une anode metallique soluble et le maintien du courant tout au long de la reaction permet d'atteindre des rendements de 50 a 75% et des selectivites de l'ordre de 70 a 90% en malonate de dimethyle en jouant sur les concentrations respectives des differents reactifs. En effet, la concentration de la base est un facteur essentiel de la reaction. Trop elevee, celle-ci entraine la formation majoritaire des produits secondaires ; trop faible, elle ralentit considerablement l'activite de la methoxycarbonylation. L'equilibre formiate de methyle/methanol influe egalement mais dans une moindre mesure sur les resultats obtenus. Il semblerait que l'electrochimie entraine la regeneration du cobaltate co(co)#3pbu#3#- ou d'une ou plusieurs autres especes intermediaires du cycle catalytique probablement reoxydes au cours de la reaction.
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Bourrinet, Philippe. "Etude de la cinétique sanguine et plasmatique, de la distribution tissulaire et de l'élimination des nanoparticules de méthylidène malonate 2. 1. 2 administrées par voie intraveineuse chez le rat." Paris 5, 1992. http://www.theses.fr/1992PA05P163.
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ALMEIDA, Sinara Mônica Vitalino de. "Síntese, caracterização e aplicação biotecnológica do Dimetil-2-(Acridin-9-metileno) malonato." Universidade Federal de Pernambuco, 2011. https://repositorio.ufpe.br/handle/123456789/2257.
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Previous issue date: 2011Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
O presente trabalho teve por objetivo sintetizar e caracterizar parcialmente as propriedades luminescentes do derivado de acridina (LPSF/IP-81) e de seu conjugado com a lectina Concanavalina A (Con A). A síntese do LPSF/IP-81 foi realizada a partir de AC-2 e dimetilmalonato, por aquecimento à 110 °C por 24 h com rendimento de 33%. Avaliação por técnicas espectroscópicas das propriedades luminescentes do LPSF/IP-81 mostrou que o mesmo é fotoluminescente por meio de excitação em 360 nm, e emissão por volta de 428 nm. No entanto o LPSF/IP-81 mostrou-se fracamente quimiluminescente quando excitado a partir de reação química com peróxido de hidrogênio. O rendimento quântico luminescente foi de 2%. LPSF/IP-81 foi conjugado com a lectina Con A e o conjugado foi separado usando cromatografia de exclusão molecular com Sephadex G-25. O conjugado Con A-IP-81 foi avaliado por meio da atividade hemaglutinante, conteúdo protéico e luminescência (fluorescência ou quimiluminescência). Análise por dicroísmo circular mostrou manutenção da estrutura terciária da Con A após conjugação com LPSF/IP-81. Medidas de fluorescência do conjugado Con A-IP-81 demonstraram manutenção das propriedades luminescentes do LPSF/IP-81. Con A-IP-81 foi empregado como sonda histoquímica, onde o LPSF/IP-81 atuou como marcador luminescente, na avaliação do perfil sacarídico de superfície celular de tumores humanos de pele e mama. A marcação dos tecidos foi avaliada em luminômetro e microscópio de fluorescência. Os tumores de pele analisados ceratoacantoma (1,992 ± 177 RLU), ceratose actínica (2,127 ± 332 RLU), carcinoma epidermóide (2,920 ± 721 RLU) e carcinoma basocelular (2,934 ± 579 RLU) mostraram uma maior expressão de resíduos de α-D-glicose/manose reconhecidos pelo conjugado Con A-IP-81 comparado aos tecidos normais (579 ± 145 RLU). Da mesma forma que os tecidos de mama e pele analisados pela microscopia de fluorescência mostraram marcação positiva para o mesmo conjugado. Esses resultados indicam que o LPSF/IP- 81 pode ser usado como marcador em histoquímica
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Alquier-Bousquet, Yolène. "Nouveaux concepts pour des médicaments anti-VIH : protéonanoparticules de poly méthylidène malonate 2.1.2. recouvertes de serum albumine humaine." Paris 5, 1998. http://www.theses.fr/1998PA05P168.
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Wouterlood, Madeleine. "Carboxylates in the rhizosphere of chickpea (Cicer arietinum) in relation to P acquisition." University of Western Australia. School of Plant Biology, 2005. http://theses.library.uwa.edu.au/adt-WU2005.0029.
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[Truncated abstract] The highly weathered, phosphorus-fixing soils of Western Australia require large amounts of P fertiliser to produce acceptable crop yields. Chickpea (Cicer arietinum L.) is an important leguminous crop that is increasingly used in rotations with wheat (Triticum aestivum L.), Western Australia’s major crop. Chickpea and a range of other species exude P-mobilising carboxylates into the rhizosphere. Plants that exude carboxylates may need less P fertiliser or may use P in the soil that is unavailable to other plants. There is a wealth of information about P mobilisation and carboxylate exudation by white lupin; in contrast, research on carboxylate exudation by chickpea is fairly limited. The major aim of this PhD research project was to investigate the relationships between exudation of carboxylates and soil and plant P status for chickpea ... In conclusion, whereas carboxylate exudation of plants such as white lupin is clearly targeted at P acquisition, chickpea showed constitutive carboxylate exudation mainly of malonate into the rhizosphere in a series of experiments, each with a different design. Unlike white lupin, chickpea forms associations with mycorrhizal fungi that may improve plant P status. Some of the functions of constitutive carboxylate exudation by chickpea may include P acquisition and deterring microorganisms, but the exact reasons and mechanisms remain unresolved.
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Hess, Jeremy P. "Synthesis of isotopically labeled substrates, lipid peroxidation products, and a novel metabolite, 2-(aminomethyl)malonate, for use in metabolic research." Case Western Reserve University School of Graduate Studies / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=case1586521864090244.
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Le, Visage Catherine. "Developpement de microparticules de poly(methylidene malonate 2. 1. 2) : application a l'induction d'une tolerance immunitaire par voie orale(doctorat : pharmacotechnie et biopharmacie)." Paris 11, 1999. http://www.theses.fr/1999PA114824.
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Vangrevelinghe, Eric. "Etude par modélisation moléculaire d'un polymère à usage thérapeutique : le poly(méthylidène malonate 2.1.2), structure tridimensionnelle, propriétés moléculaires et influence de la solvatation." Orléans, 2000. http://www.theses.fr/2000ORLE2062.
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La vectorisation et la libération contrôlée de molécules bioactives représentent un des enjeux thérapeutiques actuels. L'utilisation de particules colloi͏̈dales permet une plus grande spécifité d'action des molécules médicamenteuses, de diminuer leur toxicité potentielle, tout en les protégeant de la dégradation et en leur offrant une meilleure pénétration intracellulaire. Ces particules colloi͏̈dales peuvent être à base de polymères, ce qui leur confère une plus grande stabilité et plus de résistance dans l'organisme. C'est ainsi que les polymères et oligomères dégradables à base de méthylidène malonate ont été développés et sont particulièrement intéressants de part leur faible toxicité. L'utilisation potentielle de ces produits a conduit à initialiser une étude par modélisation moléculaire. Parmi les méthodes de modélisation que nous avons employées, celle qui semble la plus adaptée à l'étude des composés du type PMM 2. 1. 2 est la dynamique moléculaire avec une solvatation explicite. Malgré les temps de calculs importants que nécessite cette méthode, c'est celle qui conduit à des résultats les plus stables et donc plus significatifs.
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Müller, Susanna-Katharina Müller Susanna-Katharina. "Reduktive Cobalt-Alkylierung von Cobester mit einem chiralen Thiomalonat : eine Modellverbindung für die Methylmalonyl-Succinyl-Umlagerung ; Untersuchungen zur Enantioselektivität von PLE an disubstituierten Malonaten /." Bern : [s.n.], 1988. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Fournier, Elvire. "Utilisation de poly(méthylidène malonate) 2. 1. 2 dans la formulation de microsphères pour implantation intracérébrale : Application à la chimiothérapie interstitielle des gliomes malins." Angers, 2002. http://www.theses.fr/2002ANGE0001.
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Studer, Peggy. "Synthèse et caractérisation de polymères fonctionnalisés et de copolymères à base de méthylidene malonate 2. 1. 2. : application à la vectorisation de principes actifs." Mulhouse, 2001. http://www.theses.fr/2001MULH0651.
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Le présent travail a consisté à mettre au point une nouvelle gamme de copolymeres à blocs à base d'un polymère bioérodable, le méthylidène malonate 2. 1. 2. La qualité de la vectorisation d'un principe actif dans l'organisme conditionnant l'efficacité de l'acte thérapeutique, notre objectif a été d'adapter au mieux la composition chimique et la structure du principe actif, qu'il soit hydrophobe ou chargé comme l'ADN. La première partie de ce manuscrit a été consacrée à un rappel des concepts généraux de la Sectorisation. Nous avons décrit les principaux systèmes colloi͏̈daux et biopolymères développés à l'heure actuelle, ainsi que les récents progrès effectués en vectorisation notamment en termes de ciblage cellulaire actif. Par ailleurs, nous avons montré dans quelles mesures les polymères dits "canoniques" sont adaptés à la vectorisation d'ADN. Dans une deuxième partie, nous avons décrit la synthèse par voie anionique de copolymères à blocs poly(méthylidène malonate 2. 1. 2)-b-poly(oxyde d'éthylène) fonctionnalisés par une fonction chimique réactive. Introduite lors de l'amorçage de la polymérisation, cette extrémité réactive peut servir ultérieurement de site d'ancrage pour une molécule "pilote", facilitant ainsi la reconnaissance de la particule par des récepteurs de la cellule cible. Nous avons ensuite étudié la transformation chimique de cette fonctionnalité en une autre fonction chimique ainsi que son couplage avec différents types de ligands. Nous avons notamment sélectionné un dérivé saccharidique, une vitamine, des peptides ainsi qu'un marqueur, la fluorescéine, lequel permet de visualiser les particules in vitro. L'étude de la micellisation de ces copolymères a révélé que les copolymères fonctionnalisés suivent globalement le modèle théorique de Zhulina-Birshtein et que la nature de la fonctionnalité a peu d'incidence sur le diamètre moyen des micelles. Enfin, nous avons proposé la synthèse de nouveaux copolymères canoniques séquences à base de poly(méthylidène malonate 2. 1. 2) et d'un polymère canonique, le poly(méthacrylate de 2-diméthylaminoéthyle). Ces derniers ont été préparés en associant deux techniques de polymérisation, la polymérisation par transfert de groupe et la polymérisation zwittérionique. Ces différents copolymères ont ensuite été utilisés pour la formulation de micelles mixtes et thermosensibles, et de nanoparticules.
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Berrah, Yacine. "Etude de différentes stratégies de modélisation de réactions complexes dans un réacteur fermé en synthèse organique : application à la réaction de cyanoéthylation du malonate de diméthyle." Lyon 1, 1991. http://www.theses.fr/1991LYO10216.
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Nous avons etudie deux approches principales de modelisation des reactions complexes de synthese organique en processus discontinu: a) une approche basee sur l'etude d'un modele empirique en utilisant la methodologie des surfaces de reponse. Le trace des surfaces d'isoreponses nous a permis de visualiser l'optimum de chacune des reponses etudiees; b) une approche basee sur l'etude d'un modele deterministe (equations de bilan matiere du reacteur ferme) plus phenomenologique, qui se ramene a la resolution d'un probleme d'identification parametrique. Nous avons mis au point un programme en langage fortran permettant l'analyse de reactions chimiques complexes aux cinetiques competitives a partir de donnees experimentales issues de cinetiques isothermes ou a temperature variable. Nous avons compare nos resultats et conclu que le modele deterministe etait previsionnel en accord avec les resultats du modele empirique
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Yalavarty, Manjeera. "PART I : ISOLATION OF DIPENTYL 2-(4-(PENTAN-3-YL) PHENYL) MALONATE FROM SANGUISORBA OFFICINALIS LABILL PART II: SYNTHESIS OF A NOVEL FAMILY OF ETHERS OF PODOCARPIC ACID." Master's thesis, University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4149.
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The goal of part I of this thesis was to isolate pure anti cancer compounds from the Russian plant Sanguisorba officinalis. This plant was selected for investigation because it showed 100% activity against leukemia (L1210 mouse leukemia cells) during the preliminary screening of approximately 100 Russian plant extracts. This work has resulted in the isolation of novel compound 11 using traditional chromatography techniques. Compound 11 was characterized with spectroscopic techniques such as IR, 1H NMR, 13C NMR, DEPT, DQCOSY and MS. Compound 11 was assigned the structure dipentyl 2-(4-(pentan-3-yl) phenyl) malonate. The goal of part II of this thesis was to synthesize novel ethers of podocarpic acid. Ethers are of great interest in biological studies and pharmaceutical applications because of their wide variety of uses in the treatment of various diseases. A novel family of ether derivatives was synthesized using podocarpic acid (a natural tricyclic diterpene derived from podocarpus species) as a template. Novel ether derivatives of podocarpic acid were synthesized from podocarpic acid in three steps. The first step involved methylation of podocarpic acid with dimethyl sulfate to form methyl-o-methyl podocarpate. The second step was iodination of methyl-o-methyl podocarpate with iodine in presence of a mercury catalyst to form 13-iodo methyl-o-methyl podocarpate. This was followed by formation of novel aliphatic ethers using a copper catalyst. Thus this research had led to the discovery of new methodology for synthesis of three novel aliphatic ether derivatives of podocarpic acid. These ethers will be tested for their biological activity against various types of cancer, tuberculosis by National Institutes of Health.M.S.
Department of Chemistry
Industrial Chemistry
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Seguantini, Adel. "Nouvelles phases hybrides dans les systèmes : M (élément de transition 3d, lanthanide ou cadium) - Carboxylate (succinate, malonate ou pyridine-2,5-dicarboxylate - Eau : Elaboration, caractérisation et étude des proprièté physique." Paris 13, 2008. http://www.theses.fr/2008PA132018.
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Plusieurs nouvelles phases ont été isolées et caractérisées dans les systèmes ternaires : M (Métal de transition 3d, lanthanide ou cadmium) – Anion carboxylate (succinate, malonate, pyridine-2,5-dicarboxylate) - Eau. La plupart de ces composés ont fait l’objet de déterminations structurales sur monocristal. Parmi les trois anions, seul l’anion succinate favorise l’obtention de composés hybrides ionrganique-organiques de structures plus compactes et donc des interactions Métal-Métal plus fortes : Trois nouveaux types structuraux ont été mis en évidence : Cu[O2C(CH2)CO2H]2. 2H2O, [Cd][(O2C(CH2)2CO2)] [Cd(OH)]2[O2C(CH2)2CO2]. Les composés des éléments de transition 3d manifestent des comportements magnétiques diverses : ferromagnétisme, ferrimagnétisme ou anti-ferromagnétisme avec des températures d’ordre faibles. Les mesures de la fluorescence dans le cas des composés aux terres rares mettent en évidence plusieurs résultats intéressants: (i) le temps de demi-vie est plus élevé pour les composés de symétrie triclinique en comparaison avec ceux de structure monoclinique, (ii) le dopage au samarium améliore nettement le temps de demi-vie, (iii) le transfert d’énergie est très important dans le cas de Ce3+ ↔ Sm3+. Enfin l’étude RMN a permis de mettre en évidence une corrélation entre déplacement chimique du 113Cd et le nombre de groupements hydroxyles premiers proches engagés dans le polyèdre de coordinance autour de ce cationSeveral new phases were isolated and characterized in the ternary systems: M (3d transition metal, lanthanide or cadmium) - Anion carboxylate (succinate, malonate, pyridine-2,5-dicarboxylate) - Water. Most of these compounds were the object of structural determinations on single crystal. Among the three anions, only succinate facilitates the obtaining of hybrid inorganic-organic compounds with more compact structures and thus stronger Metal-Metal interactions. Three new structural types were put in evidence: Cu[O2C(CH2)CO2H]2. 2H2O, [Cd][(O2C(CH2)2CO2)], [Cd(OH)]2[O2C(CH2)2CO2 ]. 3d transition elements led to compounds with various magnetic behaviours: ferromagnetism, ferrimagnetism or antiferromagnetism with weak magnetic interactions. The measures of the fluorescence in the case of rare earth compounds bring to light several interesting results: i) the half-life time is longer for the compounds of a triclinic symmetry in comparison with those of monoclinic structure, (ii) doping with the samarium improves significantly the half-life time, iii) the transfer of energy is very important in the case of Ce3+ ↔ Sm3+. Finally the study RMN allowed bringing to light a correlation between the 113Cd chemical shift and the number of hydroxyl groups engaged in the coordination polyhedron around this cation
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Patil, Dadasaheb V. "Intramolecular cyclization strategies for synthesizing medium-ring polycycles and the total synthesis of natural products." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50118.
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Carbo- and heterocyclic compounds are of great interest to chemists. Intramolecular cyclization strategies of donor-acceptor (D-A) cyclopropanes and alkylidene malonate monoamides have excellent potential for synthesis as they offer easy access to structurally-diverse compounds. The work described in this thesis accesses the scope of the In(OTf)3-catalyzed cyclization reaction of cyclopropanes and alkylidene malonate monoamides. In(OTf)3-catalyzed reactions of alkenyl and heteroaryl cyclopropyl ketones were examined in the synthesis of functionalized cyclohexenone-based derivatives (Chapter 2). Subsequent efforts to utilize a tandem cyclopropane ring-opening/Friedel-Crafts alkylation sequence of methyl 1-(1H-indolecarbonyl)-1-cyclopropanecarboxylates to prepare functionalized hydropyrido[1,2-a]indole-6(7H)-ones is discussed in Chapter 3. The extension of this tandem protocol towards the total synthesis of (±)-deethyleburnamonine is the subject of Chapter 6. Intramolecular Friedel-Crafts alkylation of N-indolyl alkylidene malonate monoamides was also examined. An In(OTf)3-catalyzed cyclization of substituted methyl 2-(1H-indole-1-carbonyl) acrylates afforded a series of 1H-pyrrolo[1,2-a]indole-3(2H)-ones (Chapter 4), whereas substrates with the indole 2-position blocked provided access to substituted 4H-pyrrolo[3,2,1-ij]quinolin-4-ones (Chapter 5).
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Nickerson, David M. "Unique Reactivity Patterns of Enhanced Urea Catalysts." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1395859006.
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Gaurat, Olivier. "Synthèse d'inhibiteurs potentiels des N-acétylglucosaminyltransférases." Paris 6, 2002. http://www.theses.fr/2002PA066409.
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Fuchs, Monica Andrea [Verfasser], and Eckhard [Akademischer Betreuer] Dinjus. "Anwendung von Komplexen mit N2O2-Chelaten auf Cyanoacrylat- und Malonat-Basis in der katalytischen Synthese organischer Carbonate aus Epoxiden und CO2 / Monica Andrea Fuchs ; Betreuer: Eckhard Dinjus." Heidelberg : Universitätsbibliothek Heidelberg, 2014. http://d-nb.info/1180299949/34.
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Bouhlel, Ahlem. "Cyclisations radicalaires oxydatives médiées par l'acétate de manganèse (III) et orientées vers la chimie médicinale." Thesis, Aix-Marseille, 2012. http://www.theses.fr/2012AIXM5501/document.
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Ce travail s'inscrit dans la recherche et le développement de nouvelles molécules à visée thérapeutique via la mise au point de cyclisations radicalaires oxydatives médiées par l'acétate de manganèse(III). Deux problématiques ont dirigé nos recherches. Tout d'abord, nous avons développé une stratégie de synthèse de prodrogues analogues de la pafuramidine, molécule antileishmanienne. Ainsi, une 1ère série d'amidoximes a été obtenue à partir de β-cétosulfones par une synthèse multi-étapes faisant appel aux réactions i) de cyclisations radicalaires oxydatives médiées par Mn(OAc)3 et ii) de couplages pallado-catalysées de Buchwald-Hartwig et de Heck. Suite à l'évaluation biologique in vitro sur Leishmania donovani et sur des cellules humaines, une 2ème série d'amidoximes et en particulier des monoamidoximes a été réalisée, ce qui a révélé une molécule présentant un index de sélectivité 40 fois plus élevé que celui de la pentamidine, médicament utilisé comme référence. Nous avons également mis au point un double couplage "one-pot" de Buchwald-Hartwig dans le but d'obtenir des produits dicouplés dissymétriques, précurseurs éventuels de futures diamidoximes. Dans une deuxième partie, nous nous sommes focalisés sur la synthèse de composés spirocycliques pouvant constituer un pharmacophore original. De ce fait, une stratégie de synthèse conduisant à divers noyaux tels des tétralines spirocycliques, des spirolactones, des spirobenzophénanthrédin-6(5H)-ones a été mise au point. Ce travail nous a également menés vers la synthèse de dérivés thiobarbiturates, analogues de composés anesthésiques ou anticonvulsivantsThis work focuses on the research and development of new therapeutic molecules through optimized radical cyclizations mediated by manganese(III) acetate. Two problematics directed our research. First, we developed analogous prodrugs of pafuramidine, an antileishmanial molecule. Thus, a 1rst series of amidoximes was obtained from β-ketosulfones by a multi-step synthesis involving i) radical oxidative cyclizations mediated by Mn(OAc)3 and ii) pallado-catalyzed Buchwald-Hartwig and Heck coupling reactions. The 1rst series being biologically evaluated in vitro, both on Leishmania donovani and human cells, a 2nd series and particularly monoamidoximes was prepared and revealed a molecule presenting a selectivity index 40 times higher than the one of pentamidine, used as reference drug compound. We also developed a one-pot double Buchwald-Hartwig coupling reaction in the aim to obtain dissymmetric dicoupled products, potential precursors of future diamidoximes. In a second time, we focused on the synthesis of spirocyclic compounds which could constitute an original pharmacophore. Therefore, we performed a synthesis allowing access to a wide variety of scaffolds such as spirocyclic tetralins, spirolactones, spirobenzophenanthridin-6(5H)-ones. This work allowed the synthesis of thiobarbiturates, analogous of anesthetic or anticonvulsive compounds
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Chung, Chi-Lin, and 鍾琪琳. "DMAP-Catalyzed Synthesis of Quinoxalines and Methyl 2-oxo-2-arylethyl malonates in PEG-400." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/77162629879822341609.
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碩士高雄醫學大學
藥學研究所
99
Quinoxalines constitute the basis of many insecticides, fungicides and anthelmintics, as well as being important in human health and as receptor antagonists. Methyl 2-oxo-2-arylethyl malonates is the precursors of γ-butenolides. The r-butenolide structural subunit is present in a growing number of natural products and synthetic compounds with wideranging biological properties. Polyethylene glycols (PEG) are well-known to be inexpensive, recoverable, non-toxic, thermally stable, and biological compatible polymers. Polyethylene glycols are most commonly employed as a support or a phase-transfer catalyst in various organic transformations. Compared with classical molecular solvents, the polyethylene glycols are environmentally benign reaction media. In this work, catalytic reaction of DMAP and PEG-400 will be applied to prepare quinoxaline derivatives and methyl 2-oxo-2-arylethyl malonates.
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Tsai, Chien-Li, and 蔡建利. "Asymmetric Allylation of Dimethyl Malonate by Azadibenzocycloheptenone-derived Sulfinamide Chiral Ligand." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/u9jkk2.
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Lai, Yun-Yu, and 賴昀佑. "Bis(perfluorophenyl) Malonate &; Potassium-Chelating 2-Hydroxymethyl-18-Crown-6 for Organic Solar Cell Applications." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/xf9yk2.
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LAI, MING-YI, and 賴明義. "Study on the cyclization of unsaturated Ketone with malonate and GC/MS analysis of the product." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/72356296861945281824.
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Hsu, Wei-Ti, and 徐維悌. "Oscillating and Kinetic study of Bromate-Ethyl Hydrogen Malonate Reaction Catalyzed by Ce(III),Mn(II) and Ferriin." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/64930447860387947042.
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碩士國立成功大學
化學系
84
The Ce(III), Mn(II) or Fe(phen)32+ -catalyzed redox reaction of bromate ionwith 1M aqueous sulfuric acid exhibits oscillating behavior in the concentrationof bromide as well as metal ion. The induction period is shortened by the presence of bromomalonic acid under the catalysis by Ce(III) or Mn(II) ion whereas it is not shortened under the catalysis by Fe(phen)32+ ion.The induction period is about 1 hour under the catalysis of Ce(III) or Mn(II)and no induction period exists under the catalysis of Fe(phen)32+ ion.The kinetics of the oxidation of EHM by Ce(IV), Mn(II), or Fe(phen)33+ in 1M aqueous sulfuric acid were studied by using[the spectrophotometric method . In general, the rate law can be described as-d[M(n+1)+]/dt=k2 [EHM][M(n+1)+]/(Km+[EHM])( M(n+1)+ = Ce(IV), Mn(III) or Fe( phen)33+ )The order of relative reactivity toward oxidizing EHM is Mn(II) > Ce(IV) >Fe(phen)33+ under aerobic condition and Mn( II) = Ce(IV) > Fe(phen)33+ under anaerobic condition.
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Serrano, Hector doctor of pharmacy. "Characterization of the activities of trans-3-chloroacrylic acid dehalogenase and cis-3-chloroacrylic acid dehalogenase and malonate semialdehyde decarboxylase homologues : mechanism and evolutionary implications." 2009. http://hdl.handle.net/2152/17772.
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Members of the tautomerase superfamily are characterized by a [beta-alpha-beta] structural fold motif as well as a catalytic N-terminal proline (Pro-1). Three members of the superfamily are involved in the degradation of the nematocide 1,3-dichloropopene; trans-3-chloroacrylic acid dehalogenase (CaaD), cis-3-chloroacrylic acid dehalogenase (cis-CaaD) and malonate semialdehyde decarboxylase (MSAD). CaaD and cis-CaaD are involved in the hydration of their respective 3-chloroacrylic acid isomers to generate malonate semialdehyde. Subsequently, MSAD is responsible for catalyzing the decarboxylation of malonate semialdehyde to generate acetaldehyde. All three of these enzymes contain an N-terminal proline (Pro-1) that functions as a general acid, in contrast to other tautomerase superfamily members, such as 4-oxalocrotonate tautomerase (4-OT) and macrophage migration inhibitory factor (MIF), where Pro-1 acts as a catalytic base. Two new members of the tautomerase superfamily have been cloned and characterized; FG41 MSAD, a homologue of MSAD from Coryneform Bacterium strain FG41, and Cg10062, a homologue of cis-CaaD from Corynebacterium glutamicum, with low-level cis-CaaD and CaaD activities. As part of an effort to delineate the mechanisms of CaaD, cis-CaaD and Cg10062, secondary activities for all three enzymes were characterized. The three enzymes function as efficient phenylpyruvate tautomerases (PPT), converting phenylenolpyruvate to phenylpyruvate. The activity also indicates that the active site of these three enzymes can ketonize enol compounds, thereby providing evidence for the presence of an enediolate intermediate. The characterization of FG41 MSAD uncovered an activity it shares with MSAD. FG41 MSAD catalyzes the hydration of 2-oxo-3-pentynoate, but at a rate that is 50-fold less efficient than that of MSAD (as assessed by kcat/Km values). Mutagenesis studies of FG41 MSAD revealed that a single mutation resulted in a 8-fold increase in the activity. The characterization of Cg10062 and attempts to enhance the low-level cis-CaaD activity demonstrated the need for a bacterial screen that could screen a library of mutants. The resulting bacterial screen could be used to screen other members of the superfamily for dehalogenase activity. An in-depth exploration of the Cg10062 and FG41 MSAD activities may lead to a better understanding of the mechanism of cis-CaaD and MSAD and further delineate the evolutionary pathway for the tautomerase superfamily.text
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Hsu, Chia-chen, and 徐葭蓁. "Studies on the Hydrolytic Enzymes of Isoflavone in Soybean:Ⅰ: Molecular Cloning and Characterization of Glycine max β-Glucosidase that Serves to Deglucosylate Isoflavone GlucosidesⅡ: Isolation and Purification of Isoflavone 7-O-Glucoside-6”- malonate Malonylesterase in Soybean." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/47315371145834953792.
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碩士國立臺灣大學
農業化學研究所
101
Soybean (Glycine max L.) is widely consumed in food and food processing. In soybean, it contains many bioactive components including isoflavones which have estrogenic effects. Soy isoflavones are known to occur in 12 conjugation forms. The predominant forms are malonylglucosides and glucosides, but aglycones were absorbed faster and in greater amounts than their glucosides in humans. Therefore, the bioavailability of isoflavones is able to be improved when malonylglucosides are hydrolyed by malonylesterase and β-glucosidase to produce aglycones. In our previous work, a novel Glycine max β-glucosidase (GmBGL) was isolated from soybean okara and ten N-terminal amino acids were determined. In the first part of this thesis, GmBGL gene was cloned from soybean according to Phytozome blast search with this N-terminal partial sequence. The cDNA of GmBGL contained an ORF (open reading frame) of 1884 bp coding for 627 amino acids. Sequence analysis revealed that the gene encodes a 69 kDa enzyme, which has a theoretical isoelectric point at 8.98. The GmBGL was expressed in rice (Oryza sativa L.) under the control of the constitutive ubiquitin promoter by Agrobacterium-mediated transformation. The recombinant GmBGL expressed in rice catalyzed the hydrolysis of glucosides (genistin and daidzin) to produce aglycones (genistein and daidzein). This result confirmed that GmBGL was indeed a fuctional β-glucosidase gene. Based on the alignment analysis of the deduced amino acid sequence of GmBGL and other plant β-glucosidase, GmBGL was assigned to glycosyl hydrolases family 3 and contained the conserved motif which is thought to be the active site in family 3 members. Analysis of gene expression in various tissues of soybean showed that the GmBGL transcript was presented in stem, pod and mature seed and particularly highly accumulated in root and leaf. The second part of this thesis is to isolate the malonylesterase which is capable specificity to hydrolyze malonylglucosides into simple glucosides of isoflavone. Soybeans were soaked and then homogenized to prepare soybean milk. Isolation processes of the malonylesterase involved using calcium chloride to remove the intrinsic storage protein of soybean, ammonium sulfate fractionation, and DEAE anion exchange chromatography. The results indicated that the supernatant from 0.5% (w/v) calcium chloride showed a superior esterase activity. 40-50% saturation interval of ammonium sulfate precipitation possessed the most specific activity of malonylesterase. After further fractionation by DEAE anion exchange chromatography, an active esterase band was detected through Native PAGE and zymographic analysis and moreover, the corresponding protein also showed high specificity to malonylglucosides. In this purification process, the activity recovery of malonylesterase was 0.208% with a 73-fold purification efficiency.