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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Pyrrolo[2,3-d]pyrimidines : conception, synthèse, fonctionnalisation / Pyrrolo[2,3-d]pyrimidines : design, synthesis, functionalisation

Prieur, Vanessa 08 December 2015 (has links)
Les pyrrolo[2,3-d]pyrimidines, également connues sous le nom de 7-déazapurines, sont une classe importante d’hétérocycliques aromatiques, de par leurs potentiels biologiques (antitumoral, antiinflammatoire, antibactérien, etc.). C’est pourquoi ce squelette a été une source d’intérêt pour les chimistes organiciens. Outre leurs atouts biologiques, ces molécules présentent également de remarquables propriétés physico-chimiques (fluorescence UV), ce qui permet de nouvelles applications en électronique. Bien que ces dernières années, un bon nombre de recherche ont été mises en oeuvre en vue de synthétiser ces molécules, il n’existe encore que peu de méthodes générales pour obtenir des pyrrolo[2,3-d]pyrimidines hautement substituées. Le but de ces travaux de thèse est de développer différentes stratégies régiosélectives et chimiosélectives de synthèse pour accéder à des pyrrolo[2,3-d]pyrimidines diversement substituées et ce, en un minimum d’étapes. Dans un premier temps, il a été synthétisé une famille de 7-méthylpyrrolo[2,3-d]pyrimidines 4,5,6 triarylées notamment via l’utilisation de deux réactions de Suzuki-Miyaura. Pour faire suite, nous avons envisagé la préparation d’une série de pyrrolopyrimidines 2,4,6-triarylées où le motif aromatique de la position 2 est introduit suivant les conditions de Liebeskind-Srogl. Enfin la préparation de pyrrolo[2,3-d]pyrimidines 4-aminées à partir d’alkynylpyrimidines a été mise au point et divers composés de cette famille ont été élaborés. / The pyrrolo [2,3-d]pyrimidines, also known as 7-deazapurines, are an important class of aromatic heterocycles by their biological potencial (antitumor, anti-inflammatory, antibacterial, etc.). Therefore, this skeleton is a source of interest for the organic chemists. A part of the biological activity, these compounds present also outstanding physicochemical properties (UV-fluorescence); enabling new applications in electronics. The last few years, a great number of researches have been put in execution with a view to synthesizing these molecules, where still few general methods exist to obtain pyrrolo [2,3-d] pyrimidines highly substituted. The aim of these works of thesis is to develop different regioselective and chemoselective synthetic strategies to accede to pyrrolo [2,3-d]pyrimidines diversely substituted and furthemore in a reduced number of steps. First has been synthesized a family of 4,5,6-triarylated-7-methylpyrrolo[2,3-d]pyrimidines including the use of two Suzuki-Miyaura's reactions. Also we contemplated the preparation of a series of 2,4,6-triarylated pyrrolopyrimidines where the aryl group at the position 2 has been introduced under Liebeskind-Srogl reaction conditions. Finally the preparation of 4-aminated pyrrolo [2,3-d] pyrimidines from alkynylpyrimidines has been fine-tuned and diverse derivative compounds have been synthesized.
62

Synthèse et fonctionnalisation de nouveaux dérivés d’indazoles à visée thérapeutique / Synthesis of new indazoles derivatives with therapeutic potential

Naas, Mohammed 10 May 2016 (has links)
L’accès à de nouveaux composés hétérocycliques originaux biologiquement actifs nécessite la mise au point de nouvelles méthodes de synthèse rapides et efficaces. Dans ce contexte, nous nous sommes intéressés à la réactivité des indazoles. Dans la première partie, nous avons étudié la sélectivité des couplages de type Suzuki, pour fonctionnaliser la position 3 d’indazoles possédant la fonction NH libre. Par la suite, un nouveau procédé d’(hétéro)arylation direct pallado-catalysé régiosélectif a été mis à profit pour synthétiser des indazoles fonctionnalisés tant sur la position 3 que sur le sommet 7. Nous avons ensuite montré la possibilité d’accéder à des entités disubstituées indazoliques en une seule étape, via une procédure "one-pot". Afin d’accroître la diversité autour du noyau indazole, nous avons mis au point une réaction d’alcénylation oxydative pallado-catalysée, des (2H)- et (1H)-indazoles sur les sommets C-3 et C-7. Pour exemplifier cette méthodologie, nous avons développé une synthèse en trois étapes du Gamendazole, composé actuellement en phase clinique pour la contraception masculine et ce, en utilisant l’alcénylation directe en C3 d’(1H)-indazoles convenablement fonctionnalisés. Le dernier volet de ce mémoire a été consacré à la préparation de composés à structure indazolique contenant une fonction sulfonamide afin de générer des librairies de dérivés substitués par un tel motif, dans le but de les tester biologiquement dans le domaine des anticancéreux. / Access to new biologically active compounds requires the development of new rapid and efficient methods for the synthesis of original heterocyclic scaffolds. In this context, we decided to focus particularly on the reactivity of indazoles. First, we studied the selectivity of Suzuki cross-coupling reaction to functionalize position 3 of the indazole with the free NH function. Indeed, we have described the first example of the direct and regioselective palladium-catalyzed (hetero)arylation of indazoles, the reaction may be induced to occur at either in position 3 and 7. We then showed the possibility of "one-pot" synthesis of disubstituted indazolic entities. Moreover, in order to increase diversity around the indazole scaffold, we developed a direct and regioselective alkenylation of (2H)- and (1H)-indazoles by oxidative palladium catalyzed at the C-3 and C-7, then we envisaged a three staps synthesis of Gamendazole, molecule currently in clinical phase for male contraception, by using the direct alkenylation at C3 of the suitably functionalized (1H)-indazoles. The last part of this report was dedicated to the preparation of indazoles containing a sulphonamide function, with the aim of biological testing them as potentially anti-cancer candidates.
63

Estudo da reação de modificação do poli(cloreto de vinila) com nucleófilos nitrogenados e das aplicações como suporte em reações de acoplamento / Study the reaction of modification of poly(vinyl chloride) with nitrogen nucleophiles and applications as substrates for coupling reactions

Pâmella Santos de Souza 23 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho foi realizada a modificação química do poli(cloreto de vinila) (PVC) pela sua reação com azida de sódio, onde alguns dos seus átomos de cloro foram substituídos por azidas. Em seguida o grupo incorporado foi transformado em triazóis por uma reação de cicloadição 1,3 entre o polímero modificado e propiolato de etila, sendo a reação catalisada por iodeto de cobre. Essas reações foram conduzidas sob aquecimento convencional e empregando irradiação de micro-ondas. Inicialmente, a reação incorporou 20% de triazol no PVC, sendo avaliadas as condições reacionais ideais. Essas condições foram usadas para a formação de novos copolímeros com diferentes teores de triazóis incorporados. Os produtos obtidos foram usados para o suporte de paládio que é utilizado como catalisador na reação de Suzuki-Miyaura. Todos os copolímeros foram caracterizados por espectroscopia na região do infravermelho com transformada de Fourier (FTIR) / In this work was performed the chemical modification of poly(vinyl chloride) (PVC) by its reaction with sodium azide, in which some of their chlorine atoms has been replaced with azides. Then the azide group was converted to 1,2,3-triazoles by a 1,3-cycloaddition reaction between the modified polymer and ethyl propiolate, the reaction was catalyzed by copper iodide. These reactions were conducted using conventional heating and microwave irradiation. Initially, the reaction incorporated triazole in 20% of PVC, the optimal reaction conditions was evaluated. These conditions were used for the formation of new copolymers with different amounts of incorporated triazoles. The products obtained were used as a support for palladium, which is used as a catalyst in Suzuki-Miyaura reaction. All copolymers were characterized by infrared spectroscopy, Fourier transform spectroscopy (FTIR)
64

Estudo da reação de modificação do poli(cloreto de vinila) com nucleófilos nitrogenados e das aplicações como suporte em reações de acoplamento / Study the reaction of modification of poly(vinyl chloride) with nitrogen nucleophiles and applications as substrates for coupling reactions

Pâmella Santos de Souza 23 March 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Neste trabalho foi realizada a modificação química do poli(cloreto de vinila) (PVC) pela sua reação com azida de sódio, onde alguns dos seus átomos de cloro foram substituídos por azidas. Em seguida o grupo incorporado foi transformado em triazóis por uma reação de cicloadição 1,3 entre o polímero modificado e propiolato de etila, sendo a reação catalisada por iodeto de cobre. Essas reações foram conduzidas sob aquecimento convencional e empregando irradiação de micro-ondas. Inicialmente, a reação incorporou 20% de triazol no PVC, sendo avaliadas as condições reacionais ideais. Essas condições foram usadas para a formação de novos copolímeros com diferentes teores de triazóis incorporados. Os produtos obtidos foram usados para o suporte de paládio que é utilizado como catalisador na reação de Suzuki-Miyaura. Todos os copolímeros foram caracterizados por espectroscopia na região do infravermelho com transformada de Fourier (FTIR) / In this work was performed the chemical modification of poly(vinyl chloride) (PVC) by its reaction with sodium azide, in which some of their chlorine atoms has been replaced with azides. Then the azide group was converted to 1,2,3-triazoles by a 1,3-cycloaddition reaction between the modified polymer and ethyl propiolate, the reaction was catalyzed by copper iodide. These reactions were conducted using conventional heating and microwave irradiation. Initially, the reaction incorporated triazole in 20% of PVC, the optimal reaction conditions was evaluated. These conditions were used for the formation of new copolymers with different amounts of incorporated triazoles. The products obtained were used as a support for palladium, which is used as a catalyst in Suzuki-Miyaura reaction. All copolymers were characterized by infrared spectroscopy, Fourier transform spectroscopy (FTIR)
65

Síntese de 2-aril e 2,5-diarilfuranos funcionalizados: potenciais sondas fluorescentes / Synthesis of functionalized 2-aryl and 2,5-diarylfurans: potential fluorescent probes

Giancarlo di Vaccari Botteselle 14 September 2009 (has links)
A utilização de sondas fluorescentes para marcação ou detecção de biomoléculas de interesse em processos biológicos distintos, vem recebendo grande atenção em pesquisas biomédicas, de análises clínicas e biologia celular. Em geral, estas sondas fluorescentes são constituídas por moléculas orgânicas pequenas, as quais apresentam características fluorescentes e capacidade de conjugar-se com estas biomoléculas. Desta forma, esta dissertação descreve inicialmente a síntese de compostos 2-aril ou 2,5- diarilfuranos e tiofenos (3, 5, 7 e 9a-i), a partir de espécies orgânicas de telúrio (1, 4, 6 e 8) e sais de ariltrifluoroboratos de potássio (2a-i), via reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio [ver a figura no arquivo original]. Em seguida, descreve a síntese de um derivado 2,5-diarilfurano assimétrico, o 2-(3-aminofenil)-5-(4-metoxifenil)furano 11, o qual apresenta propriedades químicas e luminescentes adequadas para atuar como uma nova e promissora sonda fluorescente em processos de marcação ou detecção biológica. A síntese desta nova sonda, também chamada de 3-AFA (3-AnililFuranoAnisol), foi realizada a partir da reação de acoplamento cruzado tipo Suzuki-Miyaura, sob catálise de paládio, entre o ácido (3-aminofenil) borônico 5e e o 2- (butiltelanil)-5-(4-metoxifenil)furano 10 em 65 % de rendimento. Esta nova sonda 3-AFA 11 foi conjugada com uma série de L-aminoácidos 12a-l, a partir de uma reação de acoplamento peptídico para formação dos respectivos produtos 13a-l em rendimentos satisfatórios. Estes produtos conjugados 13a-l, apresentam potencial para marcação fluorescente de enzimas proteolíticas de interesse [ver a figura no arquivo original]. Adicionalmente, foram caracterizadas propriedades fotofísicas importantes desta nova sonda 3-AFA 11, entre as quais seus espectros eletrônicos de absorção e emissão de fluorescência, que obtiveram valores de λex a 320 nm e λem a 400 nm, respectivamente. Por fim, foi testado o potencial de acúmulo intracelular da sonda 3-AFA 11 em sistemas celulares tais como: eritrócitos infectados com Plasmodium chabaudi e amastigotas de Leishmania L. amazonensis, sendo possível observar em todos os casos a marcação fluorescente dos respectivos parasitas. / The use of fluorescent probes for labeling or detection of biomolecules of interest in different biological processes, has received much attention in biomedical, clinical testing and cell biology research. In general, these fluorescent probes are composed of small organic molecules, which have fluorescent features and ability to combine with these biomolecules. Thus, this work initially describes the synthesis of 2-aryl or 2,5-diarylfurans and thiophenes (3, 5, 7 and 9a-i) from organic species of tellurium (1, 4, 6 and 8) and potassium organotrifluoroborate salts (2a-i) by palladium catalyzed Suzuki-Miyaura crosscoupling reaction [see the figure in the original file]. After describe the synthesis of a unsymmetrical 2,5-diarylfuran derivative, the 2-(3-aminophenyl)-5-(4-methoxyphenyl)furan 11, which presents chemical and luminescent properties appropriate to act as a promising new fluorescent probes in processes of marking or biological detection. The synthesis of this new probe, also called 3-AFA (3-AnilylFuranAnisole), was performed from palladium catalyzed Suzuki-Miyaura cross-coupling reaction, between (3- aminophenyl) boronic acid 5e and 2-(butyltellanyl)-5-(4-metoxyphenyl)furan 10 in 65 % yields. This new probe 3-AFA 11 was combined with a series of Lamino acids 12a-l from a peptidic coupling reaction to obtain their products 13a-l in satisfactory yield. These combined products 13a-l show a potential for fluorescent marking of proteolitic enzymes [see the figure in the original file]. Additionally, important photo physical properties of this new probe 3-AFA 11 were characterized. These include their electronic spectra of absorption and fluorescence emission, who obtained values of λex to 320 nm and λem to 400 nm, respectively. Finally, we tested the potential of probe 3-AFA 11 for intracellular accumulation in cellular systems such as: erythrocytes infected with Plasmodium chabaudi and amastigotes of Leishmania L. amazonensis, in all cases the fluorescent uptake cellular of their parasites can be observed.
66

Étude de ligands de type biguanide dans le couplage de Suzuki-Miyaura dans l'eau

Fortun, Solène 12 1900 (has links)
No description available.
67

Über chirale Phosphinoferrocene und deren Anwendung in der (atropselektiven) Synthese räumlich gehinderter Biaryle über eine Suzuki-Miyaura-Reaktion

Schaarschmidt, Dieter 15 December 2014 (has links)
Die vorliegende Dissertation beschäftigt sich mit der Synthese und Charakterisierung drei verschiedener Typen chiraler Phosphinoferrocene sowie deren Anwendung in der Palladiumkatalysierten Suzuki-Miyaura-Reaktion. Der Schwerpunkt liegt dabei auf Untersuchungen zur Synthese räumlich gehinderter Biaryle sowie auf atropselektiven Biarylkupplungen. Über eine Ullmann-artige Kupplung von Iodferrocen mit sekundären Alkoholen wurden zunächst chirale Ferrocenylalkylether synthetisiert, die mit Hilfe dirigierter Lithiierungen in 1,1'-disubstituierte Phosphinoferrocene der Art Fe( 5-C5H4OR)( 5-C5H4-C6H4-2-PR'2) sowie planar-chirale 1,2,1'-trisubstituierte Ferrocene des Typs Fe( 5-C5H3-1-PPh2-2-OR)( 5-C5H4SiMe3) überführt werden konnten. Erstere eignen sich für die Umsetzung räumlich gehinderter Arylhalogenide in der Suzuki-Miyaura-Reaktion, wobei die katalytische Produktivität mit sinkendem Tolman Kegelwinkel der Phosphine steigt. Darüber hinaus ist es möglich, Kupplungsreaktionen zwischen nicht aktivierten Bromaromaten und Phenylboronaäure bei ultraniedriger Katalysatorbeladung (1 ppm) durchzuführen. Die 1,2-P,O-substituierten Ferrocene erlauben die Synthese tri-ortho-substituierter Biaryle. Dabei zeigte sich, dass die Enantioselektivität der Umsetzung hauptsächlich durch die planare Chiralität des Ferrocens und nicht durch den chiralen Alkoxysubstituenten bestimmt wird. Darauf aufbauend wurde eine Serie verschieden substituierter planar-chiraler Phosphinoalkenylferrocene der Art Fe( 5-C5H3-2-PR'2-(E)-CH=CHR)( 5-C5H5) synthetisiert. Die elektrochemische Untersuchung dieser Verbindungen zeigte, dass die -Donoreigenschaften des Phosphins durch die elektronischen Eigenschaften des alkenylgebundenen Substituenten R nicht verändert werden. Dies erlaubt die unabhängige Variation der -Donor-/ -Akzeptoreigenschaften des Phosphins und des Alkens. Abschließend wurde ein Vertreter der Phosphinoalkenylferrocene in der Synthese tri- und tetra-ortho-substituierter Biaryle sowie in atropselektiven Biarylkupplungen eingesetzt. Die Leistungsfähigkeit des Katalysators in der Suzuki-Miyaura-Reaktion wurde durch die Variation der Substratpalette untersucht.
68

Příprava a studium vlastností polymerů na bázi bis(terpyridyl)fluorenů / Preparation and characterization of bis(terpyridyl)fluorene based polymers

Hrma, Martin January 2016 (has links)
The diploma thesis presents the preparation of ,-bisterpyridinylfluorenes (unimers) containing fluorene unit in the central block either directly attached to terpyridine (tpy) end groups or via 1,4-phenylene or thiophene-2,5-diyl linker. Synthesized unimers were subsequently used for the preparation of metallo-supramolecular polymers with Zn2+ and Fe2+ ions. The prepared unimers were characterized by NMR, IR and HR-MS, their optical properties were investigated using absorption and emission spectroscopy and cyclic voltammetry. Molecular weight distribution for the prepared Fe-polymers was determined by GPC. The number-average degree of polymerization equal to 7 for an equimolar ratio between unimer and Fe2+ in a diluted solution was determined for polymers composed of unimer with thiophene-2,5- diyl linker. By using the viscometric measurements the ongoing constitutional dynamics in solutions of metallo-supramolecular polymers was proven. The overstoichiometric amount of metal ions in solution resulted in equilibrium shortening of the polymer chains together with end-capping of terminal tpy ligands by Mt2+ ions. Unimer with thiophene-2,5-diyl linker exhibited unique properties involving significantly red-shifted absorption and emission maxima, as well as the different behavior during assembling...
69

Untersuchungen zur enantioselektiven Totalsynthese von Parnafungin C / Studies towards the Enantioselective Total Synthesis of Parnafungin C

Heidemann, Sven 04 August 2016 (has links)
No description available.
70

Synthèse de nouveaux agents anticancéreux / Synthesis of new anticancer agents

Abou Hamdan, Hussein 24 September 2018 (has links)
Les cancers représentent un problème majeur de santé public d'où la nécessité de rechercher de nouvelles classes de médicaments. Parmi les pistes pour développer de nouveaux traitements, deux ont retenu notre attention et celle de nos collaborateurs : la modulation de l’épissage par des composés comme le NVS-SM2, et l’inhibition de l’oncogène KRAS par des dérivés de produits naturels, les flavaglines. Dans ce contexte, nous avons développé la première synthèse robuste du NVS-SM2, qui peut satisfaire la demande globale de cet agent pour examiner en détail son potentiel thérapeutique dans différents types d’affection. En outre, la stratégie de synthèse rapportée ici pourrait être étendue à de nouveaux analogues de ce composé. D’autre part, nous avons synthétisé de nouvelles flavaglines qui sont en cours d'étude pour leurs effets sur l’inhibition de KRAS. Au cours de cette étude, nous avons découvert de nouvelles réactions, notamment une inversion de configuration d’amines induite par du chlorure de diméthylcarbamoyle. / Cancers represent a major public health problem hence the need to use new classes of medicines. Among the opportunities for developing new treatments, two have caught our attention and that of our collaborators: the modulation of splicing by compounds such as NVS-SM2, and the inhibition of the oncogene KRAS by derivatives of natural products, the flavaglines.In this context, we have developed the first robust synthesis of NVS-SM2, which can satisfy the global demand of this agent to examine in detail its therapeutic potential in different types of disorders. In addition, the synthetic strategy reported here could be extended to new analogues of this compound. Furthermore, we have synthesized new flavaglines that have been examined for their effects on KRAS inhibition. During this study, we discovered new reactions, including a dimethylcarbamoyl chloride-induced amine inversion of configuration.

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