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Réactions médiées par l'acétate de manganèse (III) et pharmacochimie antiparasitaireTabélé, Clémence 21 September 2016 (has links)
La leishmaniose est une maladie infectieuse due à Leishmania, responsable de plus de 50 000 décès par an en ce qui concerne la forme viscérale (LV). La plupart des médicaments antileishmaniens se révèlent inefficaces (apparition de résistances avec la molécule de référence : la pentamidine) ou trop onéreux pour les patients (incidence principale en Inde). Il existe donc un réel besoin de nouveaux médicaments ne manifestant aucune résistance parasitaire, moins chers et administrables par voie orale. Dans cet objectif, plusieurs séries de monoamidoximes (de structure similaire à celle de la pentadimine) ont été synthétisées, en utilisant des réactions radicalaires médiées par l'acétate de manganèse (III), et sous irradiation micro-ondes. Des réactions pallado-catalysées ont permis de diversifier les structures obtenues : couplages de Suzuki-Miyaura et couplages originaux avec des dérivés de structure allyl alcool. Plusieurs amidoximes ont ainsi montré une bonne activité in vitro sur les formes promastigote et amastigote de Leishmania et une faible toxicité sur des lignées de macrophages, leur indice de sélectivité étant meilleur que celui de la pentamidine, utilisée comme référence. / Leishmaniasis is an infectious disease due to Leishmania : there are more than 50,000 deaths a year due to visceral form (VL). Most of antileishmanial drugs are either inefficient (too many resistances with the main drug : pentamidin) or too expensive for people (most of patients live in India). Thus, there is a real need for new drugs, without parasitical resistances, less expensive and orally administered. In this aim, several series of monoamidoxime, derivatives (pentamidine structure-like) have been synthesized using a free radical mechanism mediated by manganese (III) acetate under microwave irradiation. Palladium-catalyzed coupling reaction were also carried out for extensions of potential drugs : Suzuki-Miyaura reactions and original cross-coupling reactions involving allyl alcohol derivatives. Several amidoximes showed valuable in vitro activities toward Leishmania promastigote and amastigote forms,and low toxicity on macrophages, exhibiting a better selectivity index than pentamidine used as a drug compound reference.
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Potassium Permanganate/ Carboxylic Acid/ Organic Solvent: A Powerful Reagent For C-c Bond Formation, Aryl Coupling Reactions And Enone Oxidation Ipso-nitration Of Arylboronic Acids With Silver Nitrite/ TmsclFindik, Hamide 01 March 2009 (has links) (PDF)
The first part of the thesis presents the KMnO4/ carboxylic acid/ organic solvent which is a powerful reagent for C-C bond formation, aryl coupling reactions and enone oxidation. The a¢ / -acetoxylation of enones and the a-acetoxylation of aromatic ketones were carried out with potassium permanganate and acetic acid, in which acetoxylation products were obtained in 74-96% yields. The same reaction was carried out with carboxylic acids other than acetic acid, which furnished corresponding acyloxy ketones with the same regioselectivity. For the first time, formyloxylation products were synthesized in a 61-85% yield by using formic acid.
The potassium permanganate and acetic acid method was also used for aryl coupling reactions. The reaction of arylboronic acids and aryl hydrazines in benzene with potassium permanganate and acetic acid in turn furnished biaryls in a 85-96% yield.
We showed that potassium permanganate/carboxylic acid/organic solvent behaves as manganese(III) acetate.
In the second part of the thesis, ipso-nitration of arylboronic acids with AgNO2/ TMSCl was performed. Nitration of aromatic compounds is one of the most extensively studied reactions, and nitroaryl moieties play key roles in the physical and chemical properties of many target molecules in organic synthesis. For electrophilic nitration of aromatic compounds, a wide variety of reagents are available to date. Most of them are very strong nitrating agents and often lead to
further nitration and mixture of isomers. Since most nitrating agents are oxidants, oxidation of other functional groups can also occur, giving a mixture of products. Thus, a search for milder and selective nitrating agents is a good research goal. In this work, we aimed to apply AgNO2/ TMSCl system to ipso nitration of arylboronic acids.
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