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Syntéza polysubstituovaných pyrimidinů s potenciálními protizánětlivými vlastnostmi / Synthesis of polysubstituted pyrimidines with potential anti-inflammatory propertiesKalčic, Filip January 2017 (has links)
This thesis is engaged in the synthesis of polysubstituted pyrimidines with anti- inflammatory properties. Such molecules can inhibit production of prostaglandin E2 (PGE2). The aim of this study was to enhance water-solubility and anti-inflammatory efficacy of such derivatives via structural modifications of the lead scaffold. Among applied synthetic tools, the Suzuki-Miyaura cross-coupling was the prevalent reaction, however, many other synthetic procedures (Heck reaction, condensation, borylation, ozonolysis, nucleophilic substitution, etc.) were utilized as well. Overall, 43 final products were prepared. The anti-inflammatory efficacy (inhibition of PGE2 production) was successfully increased as the most potent compound achieved three orders of magnitude higher activity compared to the current lead structure WQE-134. Furthermore, no general influence of the length of the substituent in the C5 position of pyrimidine (C5pyr) on the anti-inflammatory efficacy of synthesized compounds was observed. Significant bioavailability obstacle in future development of the current lead WQE-134 is its poor solubility which was successfully enhanced by introduction of heteroatom bearing moieties to C5pyr. The most water-soluble compound achieved two orders of magnitude higher solubility than WQE-134 while...
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Nanoparticules de palladium comme catalyseurs : Conception, analyses et application pour la préparation de dérivés bisaryliques d'intérêt biologique. / Palladium nanoparticles as catalysts : conception, analyses and application for the preparation of bisaryl derivatives of biological interest.Cornelio, Benedetta 16 April 2014 (has links)
Un grand nombre de 3,4-bisindolylmaléimides possède une activité inhibitrice des protéine-kinases. Les 3-isothiazolone-1,(1)-(di)oxydes pouvant être considérées comme des analogues de la maléimide, la fonctionalisation des 5-chloro- et 4,5-dichloro-3-isothiazolone 1,(1)-(di)oxydes par des réactions de couplage palladocatalysé de Suzuki-Miyaura, permet d'accéder aux analogues “thia” des 3,4-bisindolylmaléimides. La synthèse de sulfonamides primaires tels que les dérivés 4-(hétéro)aryl substitués du benzènesulfonamide comme inhibiteurs potentiels de l'anhydrase carbonique, a également été envisagée dans ce travail.Une collection de matériaux hybrides constitués de nanoparticules de palladium adsorbées sur des nanostructures de carbone a été préparée et testée dans des réactions de couplages palladocatalysés, comme catalyseurs en milieu hétérogène. Le plus efficace d'entre eux, associant des nanoparticules de palladium stabilisées par le dodécanethiol et adsorbées sur des nanotubes de carbones “multi-walled”, a été employé afin de préparer vingt-quatre nouveaux dérivés 4-(hétéro)aryl substitués du benzènesulfonamide. L'échec de l'utilisation de ce catalyseur dans les reactions de fonctionalisation des isothiazolone-1,(1)-(di)oxydes nous a contraints à employer un catalyseur plus conventionnel, le PdCl2(dppf)•CH2Cl2.Le dernier volet de ce projet visait à concevoir des catalyseurs à base de nanoparticules de palladium encapsulées dans des nanofibres de carbone “grafitisées” (nanoréacteurs). Une série de nanoréacteurs a pu être préparée et nous avons étudié l'effet du confinement généré à l'intérieur de la nanofibre, sur la réaction palladocatalysée de Suzuki-Miyaura. / 3,4-bisindolylmaleimides possess an inhibitory activity against protein kinase. Because 3-isothiazolone-1,(1)-(di)oxide can be considered as maleimide analog, 5-chloro and 4,5-dichloro-3-isothiazolone-1,(1)-(di)oxide were functionalised using a palladium-catalysed Suzuki-Miyaura cross-coupling reaction achieving the “thia” analogs of 3,4-bisindolylmaleimides. We were also interested in the preparation primary sulfonamides such as 4-(hetero)aryl substituted benzenesulfonamides as carbonic anhydrases inhibitors.A series of hybrid materials comprising palladium nanoparticles adsorbed on carbon nanostructures has been prepared and tested as heterogeneous catalysts of palladium-mediated cross-coupling reactions. The best catalyst, resulting in palladium nanoparticles stabilised by dodecanethiol adsorbed on multi-walled carbon nanotubes, was employed in Suzuki-Miyaura reactions for the preparation of twenty-four new 4-(hetero)aryl substituted benzenesulfonamides. As this catalyst failed in the functionalisation of isothiazolone-1,(1)-(di)oxides, this latter was realised using a more conventional catalyst, PdCl2(dppf)•CH2Cl2.A last part of the project aimed to the conception of catalysts made of palladium nanoparticles encapsulated in graphitised carbon nanofibres (nanoreactors). We prepared a series of nanoreactors and we studied the effect of the confinement inside the nanofibre channel on the Suzuki-Miyaura cross-coupling reaction.
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Nové modifikované nukleosidy s protivirovou nebo cytostatickou aktivitou / Novel modified nucleosides with antiviral or cytostatic activityTokarenko, Anna January 2021 (has links)
A general and modular synthetic approach to 4-substituted phenyl, 2-substituted pyridin- 5-yl and 5-substituted pyridin-2-yl 2′-C-methyl-C-ribonucleosides as potential anti-HCV agents was developed. Addition of halo(het)aryllithium reagents to benzylated 2-C-methyl-D- ribonolactone gave the corresponding hemiketals, which were subsequently converted to the β-anomeric benzyl-protected bromo(het)aryl-C-nucleosides via either direct reduction (in the case of phenyl derivative) or acetylation followed by reduction of the resulting hemiketal acetates (in the case of pyridyl derivatives). The key halogenated (het)aryl-C-nucleoside intermediates were further transformed by Pd-catalyzed cross-coupling, hydroxylation and amination reactions affording series of protected C-nucleosides with small hydrophilic and hydrophobic substituents. The final protecting group removal was rather problematic, and different debenzylation methods, such as hydrogenation on Pd/C or treatment with BCl3, had to be optimized for each derivative to minimize the formation of side-products. The final C- nucleosides were also converted into their 5′-O-triphosphates, and biological activity screenings revealed that none of the free C-nucleosides possesses any antiviral activity in the HCV replicon assay, and none of their NTPs...
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Nouvelles réactions de couplages des organosilanes pour la synthèse d’esters à partir du CO₂ et de sulfones à partir du SO₂ / New coupling reactions of organosilanes for the synthesis of esters from CO₂ and sulfones from SO₂Char, Joëlle 12 September 2017 (has links)
Les couplages croisés sont des réactions très étudiées et ont même fait l’objet d’un prix Nobel. Ces réactions consistent à coupler une espèce organométallique nucléophile avec une espèce électrophile et sont la meilleure façon de former une nouvelle liaison peu ou pas polarisée telle qu’une liaison C–C ou C–S. Cependant, leur mise en place emploie souvent des nucléophiles forts limitant ainsi leur sélectivité et leur tolérance. D’abord, les organosilanes sont des nucléophiles attrayants grâce à leur abondance, leur sélectivité, leur stabilité, leur tolérance aux groupements fonctionnels, leur faible toxicité, leur manipulation facile et leur faible coût. Toutefois, leur faible nucléophilie peut représenter un défi à surmonter lors de leur utilisation. Ensuite, pour une économie d’atome maximale, le dioxyde de carbone (CO₂) représente la meilleure source de carbone et de fonction ester ; et le dioxyde de soufre (SO₂), la meilleure source de soufre et de fonction sulfone. Dans ce manuscrit sont relatées plusieurs nouvelles réactions de couplage des organosilanes pour la synthèse directe d’esters à partir du CO₂ et de sulfones à partir du SO₂. Une étude théorique et expérimentale a été réalisée pour permettre la mise en place de la réaction de couplage du CO₂ avec un arylsilane et un halogénure d’alcane, catalysée par un complexe de cuivre(I). Les caractères plus nucléophile et plus électrophile du SO₂ ont été exploités pour son couplage, sans catalyseur, avec des arylsilanes et des halogénures d’alcanes et pour son couplage, pallado-catalysé, avec des allylsilanes et des halogénures d’aryles, communément appelé le couplage de Hiyama sulfonylant. / Cross coupling reactions are well studied reactions and their development was awarded a Nobel price. These reactions aim at coupling organometallic nucleophiles and electrophiles compounds and are the best way to form a little to none polarized bond such as C–C and C–S bond. They however make use of strong nucleophiles, decreasing their selectivity and tolerance. On one hand, among all available nucleophiles, organosilanes are very attractive because of their abundance, selectivity, stability and tolerance towards functional groups, they are also less toxic, easy to handle, and cheap. Their use though is a challenge because of their lower reactivity. On the other hand, for the sake of increasing the atom economy of a reaction, carbon dioxide (CO₂) is the best source of carbon and ester functional group; and sulfur dioxide (SO₂) is the best source of sulfur and sulfone functional group. In this manuscript, we herein report several coupling reactions between organosilanes giving a direct access to esters from CO₂ and to sulfones from SO₂. Experimental and theoretical studies have been carried out to develop a coupling reaction between arylsilanes, CO₂ and alkyl halides catalyzed by a copper(I) complex. SO₂ being more electrophilic and more nucleophilic, is used in a catalyzed less coupling reaction with arylsilanes and alkyl halides and in a coupling reaction with allylsilanes and aryl halides catalyzed by a palladium(II) complex, known as sulfonylating Hiyama coupling.
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Exploiting Substituent Effects to Control the Mechanochromic Response of Spiropyran-containing CopolymersKempe, Fabian 18 May 2021 (has links)
Mechanochromic polymers respond to external force by changing their color. This can be achieved by the incorporation of a molecular switch such as spiropyran (SP) into polymers. SPs can be isomerized by mechanical force from their colorless form into colored merocyanines. Main chain copolymerization of spiropyrans allows investigation of their mechanochromic behavior and potential use as force sensors.
So far, several covalent polymer matrices have been used to investigate the mechanochromic response of SPs, among them poly(ε caprolactone) (PCL). Less investigated is how the mechanochromic response can be fine-tuned by substituent effects. First, PCL with differently substituted spiropyrans at the chain’s midpoint were used in order to investigate the effect of different substituents and their regiochemistry on the isomerization behavior of SPs under mechanical stress. A low activation barrier was observed for NO2 substitution of “ortho”-spiropyrans compared to no substitution (R = H).
In order to investigate phenyl-substituted “para,para” spiropyrans, a newly developed kinked polyarylene was employed as covalent matrix material. This new polyarylene (PmmpP) has a meta,meta,para connection in its backbone and exhibits excellent mechanical properties. Its high strength allows the isomerization of this molecular switch with a large activation barrier. The phenyl-substituted “para,para” spiropyran showed transient mechanochromism and was switched 25 times in force-and-release cycles. The synthesis of PmmpP was carried out by a Suzuki polycondensation in three steps from commercial starting materials.
To further capitalize on the simplicity and properties of PmmpP, a two step synthesis of a semifluorinated kinked polyarylene was demonstrated by direct arylation polycondensation with tetrafluorobenzene (F4). This partially fluorinated PmmpF4 was synthesized with a variety of side-chains. Resulting polymers exhibited a large range of glass transition temperatures, allowing for the production of tailor-made smart materials.
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Synthesis and photophysical property investigation of beads on a chain (BoC) silsesquioxane hybrid oligomers: probable pseudo conjugationMahbub, Shahrea 29 August 2022 (has links)
No description available.
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Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolinesLesenyeho, Lehlogonolo Godfrey 09 1900 (has links)
The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis. / Chemistry / MSc. (Chemistry)
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2-Aryl-6,8-Dibromo-4-Chloroquinazoline as scaffold for the synthesis of Novel 2,6,8-Triaryl-4-(Phenylethynyl)Quinazolines with potential photophysical propertiesPaumo, Hugues Kamdem 06 1900 (has links)
The 2-aryl-6,8-dibromoquinazolin-4(3H)-ones were prepared in a single-pot operation by condensing 6,8-dibromoanthranilamide and aryl aldehydes in the presence of molecular iodine in ethanol. Treatment of the 2-aryl-6,8-dibromoquinazolin-4(3H)-ones with thionylchloride in the presence of dimethylformamide afforded the corresponding 2-aryl-4-chloro-6,8-dibromoquinazolines. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling reaction of 2-aryl-4-chloro-6,8-dibromoquinazolines with terminal alkynes at room temperature afforded series of 2-aryl-6,8-dibromo-4-(alkynyl)quinazolines. Further transformation of the 2-aryl-6,8-dibromo-4-(phenylethynyl)quinazolines via Suzuki-Miyaura cross-coupling with arylboronic acids occurred without selectivity to afford the corresponding 2,6,8-triaryl-4-(phenylethynyl)quinazolines. The compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques as well as mass spectrometry. The absorption and emission properties of 2,6,8-triaryl-4-(phenylethynyl)quinazolines were determined in solution. / Chemistry / M.Sc. (Chemistry)
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Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolinesLesenyeho, Lehlogonolo Godfrey 09 1900 (has links)
The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis. / Chemistry / MSc. (Chemistry)
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2-Aryl-6,8-Dibromo-4-Chloroquinazoline as scaffold for the synthesis of Novel 2,6,8-Triaryl-4-(Phenylethynyl)Quinazolines with potential photophysical propertiesPaumo, Hugues Kamdem 06 1900 (has links)
The 2-aryl-6,8-dibromoquinazolin-4(3H)-ones were prepared in a single-pot operation by condensing 6,8-dibromoanthranilamide and aryl aldehydes in the presence of molecular iodine in ethanol. Treatment of the 2-aryl-6,8-dibromoquinazolin-4(3H)-ones with thionylchloride in the presence of dimethylformamide afforded the corresponding 2-aryl-4-chloro-6,8-dibromoquinazolines. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling reaction of 2-aryl-4-chloro-6,8-dibromoquinazolines with terminal alkynes at room temperature afforded series of 2-aryl-6,8-dibromo-4-(alkynyl)quinazolines. Further transformation of the 2-aryl-6,8-dibromo-4-(phenylethynyl)quinazolines via Suzuki-Miyaura cross-coupling with arylboronic acids occurred without selectivity to afford the corresponding 2,6,8-triaryl-4-(phenylethynyl)quinazolines. The compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques as well as mass spectrometry. The absorption and emission properties of 2,6,8-triaryl-4-(phenylethynyl)quinazolines were determined in solution. / Chemistry / M.Sc. (Chemistry)
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