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Construction et étude de composés fluorescents à base d'unités hydroxyphényl-s-triazines et boradiazaindacènesRihn, Sandra 13 June 2013 (has links) (PDF)
Les travaux réalisés dans le cadre de la thèse avaient pour but la synthèse de nouveaux fluorophores basés sur les unités BODIPYs et hydroxyphényl-s-triazines. Pour être utilisées comme sondes efficaces dans des applications en chimie et en biologie, les chromophores doivent présenter une forte brillance et des rendements quantiques de fluorescence élevés, une modulation aisée de ses propriétés optiques ainsi qu'une bonne stabilité chimique et photochimique. Une stratégie originale et efficace a été développée pour l'obtention de dérivés d'o-hydroxyphényl-s-triazine. Ces derniers présentent des déplacements de Stokes anormalement élevés ayant pour origine un transfert de proton intramoléculaire ultrarapide à l'état excité (ESIPT). L'extension du système π-conjugué sur les différentes plateformes de départ a été réalisée par couplages pallado-catalysés et/ou condensation de Knoevenagel, permettant ainsi d'accéder à une large gamme spectrale en absorption et en émission. Le développement d'une nouvelle voie de synthèse à permis l'obtention d'oligo-BODIPYs par couplage oxydant réalisé en associant PIFA et un acide de Lewis. Toutes les propriétés photophysiques des nouvelles sondes ont été étudiées et ont fait l'objet de discussions détaillées.
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Síntese de novos heterocíclos benzazólicos fluorescentes e sua incorporação em matrizes de celuloseKuplich, Marcelo Domingues January 2007 (has links)
Neste trabalho é apresentada a síntese e a caracterização de compostos do tipo 2-(2’- hidroxifenil)benzazóis derivados da 1,3,5-triazina, fluorescentes devido a um mecanismo de transferência protônica intramolecular no estado excitado (TPIEE). Foram preparados quatro novos corantes diclorotriazinil-(hidroxifenil)benzazólicos, que apresentam emissão de fluorescência na região azul-verde do espectro visível e deslocamentos de Stokes compatíveis com substâncias que sofrem o fenômeno da TPIEE. Estas substâncias foram caracterizadas por diversas técnicas espectroscópicas (IR, RMN e HR-MS), enquanto que as análises fotofísicas (absorção no ultravioleta-visível e emissão de fluorescência) foram realizadas em solução e no estado sólido. Os ensaios preliminares realizados indicam a possibilidade de emprego desses corantes como sondas fluorescentes de material celulósico. / The synthesis and characterization of new 2-(2’-hydroxyphenyl)benzazoles derivatives from 1,3,5-triazine, fluorescent due to an excited state intramolecular proton transfer (ESIPT) mechanism, were presented in this work. The four new dichlorotriazinylbenzazole derivatives synthesized present fluorescence emission in the blue-green region of the spectra and Stokes shift compatible with ESIPT compounds. The characterization of the new fluorescent reactive dyes by means of spectroscopic (IR, RMN, UV-Vis and fluorescence) and spectrometric (HRMS) techniques, and the study of the possibilities to dye cellulose fibers were carried out. Fluorescent cellulose fibers were prepared using the dyes and a methodology used in the industry and show no color change when observed in the visible light (white cellulose) and a blue-green fluorescence when irradiated with UV light.
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Hodnocení subchronického působení atrazinu na raka (Cherax destructor)HLÁVKOVÁ, Markéta January 2018 (has links)
The evaluation of the sub-chronic exposure to atrazine on crayfish The aim of this study is to evaluate the sub-chronic effect of atrazin on a behaviour, oxidative stress, antioxidant enzyme aktivities and biochemical profile of haemolymph in. These complex data should help to appraise the impact of this substance in the environment. The total test duration was 28 days and was divided into two periods. The first 14 days the crayfish were exposed to two concentrations of atrazine: 6.86 micrograms per liter (ATRenv = environmental concentration in the water in the Czech Republic) and 1.21 milligrams per liter (ATR10% = is coincident to 10% LC50). After the atrazine treatments the depuration 2 weeks phases in water without any chemicals followed. The results indicate that sub-chronic effect of atrazine influenced neither the behaviour of the crayfish nor the level of oxidative stress (measured by TBARS), whereas the changes of superoxiddismutase (SOD) were observed in all tissues (muscles, gills and hepatopancreas). The changes of enzyme activity were observed in catalase (CAT; hepatopancreas and the muscle tissue), glutathione S-transferase (hepatopancreas and the gills tissue), glutathione reductase (GR; the hepatopancreas tissue) and reduced glutathione (the muscle tissue). The influence of ATRenv on the biochemical profile of haemolymph at the following parameters was estimated only for lactate and alkaline, however phosphatase changes made by ATR10% were significant for glucose, ammonia, lactate and alkaline phosphatase measurements. The sub-chronical effect changed the activity of all antioxidant enzymes in hepatopancreas, muscles and the gills tissue of the observed crayfish. The presented results in this study are giving compact information of impact of atrazine on the crayfish and the whole water environment. The suggestion of using the crayfish for tests of toxicity looks like an ideal supplement for triazine herbicide estimations.
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Síntese de novos heterocíclos benzazólicos fluorescentes e sua incorporação em matrizes de celuloseKuplich, Marcelo Domingues January 2007 (has links)
Neste trabalho é apresentada a síntese e a caracterização de compostos do tipo 2-(2’- hidroxifenil)benzazóis derivados da 1,3,5-triazina, fluorescentes devido a um mecanismo de transferência protônica intramolecular no estado excitado (TPIEE). Foram preparados quatro novos corantes diclorotriazinil-(hidroxifenil)benzazólicos, que apresentam emissão de fluorescência na região azul-verde do espectro visível e deslocamentos de Stokes compatíveis com substâncias que sofrem o fenômeno da TPIEE. Estas substâncias foram caracterizadas por diversas técnicas espectroscópicas (IR, RMN e HR-MS), enquanto que as análises fotofísicas (absorção no ultravioleta-visível e emissão de fluorescência) foram realizadas em solução e no estado sólido. Os ensaios preliminares realizados indicam a possibilidade de emprego desses corantes como sondas fluorescentes de material celulósico. / The synthesis and characterization of new 2-(2’-hydroxyphenyl)benzazoles derivatives from 1,3,5-triazine, fluorescent due to an excited state intramolecular proton transfer (ESIPT) mechanism, were presented in this work. The four new dichlorotriazinylbenzazole derivatives synthesized present fluorescence emission in the blue-green region of the spectra and Stokes shift compatible with ESIPT compounds. The characterization of the new fluorescent reactive dyes by means of spectroscopic (IR, RMN, UV-Vis and fluorescence) and spectrometric (HRMS) techniques, and the study of the possibilities to dye cellulose fibers were carried out. Fluorescent cellulose fibers were prepared using the dyes and a methodology used in the industry and show no color change when observed in the visible light (white cellulose) and a blue-green fluorescence when irradiated with UV light.
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Síntese e avaliação de novos candidatos a fotoprotetores absorvedores de radiações UVA e UVB, desenhados a partir de compostos análogos a produtos naturais / Synthesis and evaluation of novel candidates for UVA and UVB absorber photoprotectors, drawn from compounds analogous to natural productsLuzin, Rangel Magalhães 29 August 2018 (has links)
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Previous issue date: 2018-08-29 / It is known that sun exposure is one of the factors that contribute greatly to the appearance of skin cancer. Cancer cases have arisen annually on the planet and many of these cases have direct correlation with sun exposure. Knowing that both UVA and UVB radiation are harmful to health when the person is overexposed, the need arises for the use of devices to protect the skin and one of these ways and already recognized by the scientific community is through the prophylactic use of protectors solar power. Thus, this work proposes the synthesis, structural characterization, thermal stability verification, molar absorptivity calculation and in vitro UVB protection factor (PFUVB) calculated by the spectrophotometric method described by Mansur of new compounds derived from structures analogous to natural products. The structural planning was based on triazine derivatives (they are already commercially used with relative efficiency) and the use of chalcones, which are structures that besides having double bonds and conjugated aromatic structures that favor the absorption of the ultraviolet radiation, are studied compounds for various purposes and present in various plants, thus constituting a natural structure. In the planning, the choice of such structures was also due to the synthesis of compounds of high molar mass (above 900 daltons), contributing to safe structures, with low toxicity probability, low skin permeation and in compliance with the demands of the current legislation. The data obtained in the work reinforce the success of the same, where we had for the prototypes synthesized, molar absorptions superior to commercial filters. Establishing aresearch with the use of chalcones in safe and efficient sunscreens. / É sabido que a exposição solar é um dos fatores de grande contribuição para o surgimento do câncer. Casos de câncer tem surgido anualmente no planeta e muitos desses casos tem direta correlação com a exposição solar. Sabendo que tanto a radiação UVA quanto a UVB são nocivas à saúde quando o indivíduo é exposto em demasia, surge a necessidade do uso de artifícios para a proteção da pele e uma dessas maneiras e já reconhecida pelo meio científico é através do uso profilático de protetores solares. Assim este trabalho se propôs a síntese, caracterização estrutural, verificação de estabilidade térmica, cálculo de absortividade molar e fator de proteção solar UVB (FPUVB) in vitro calculado pelo método espectrofotométrico descrito por Mansur de novos compostos derivados de estruturas análogas a produtos naturais. O planejamento estrutural foi baseado nos derivados triazínicos (pois já são de uso comercial com relativa eficiência) e o uso de chalconas, que são estruturas que além de possuir duplas ligações e estruturas aromáticas conjugadas que favorecem a absorção da radiação ultravioleta, são compostos bastante estudados para diversos fins e presente em vários vegetais, constituindo assim uma estrutura natural. No planejamento, a escolha de tais estruturas se deu também pela síntese de compostos de alta massa molar (acima de 900 Daltons), contribuindo para estruturas seguras, com probabilidade de baixa toxicidade, baixa permeação cutânea e atendendo aos reclames das legislações vigentes. Os dados obtidos no trabalho reforçam o sucesso do mesmo, onde tivemos para os protótipos sintetizados, absorções molares superiores a filtros comerciais. Estabelecendo assim uma nova linha de pesquisas com a utilização de chalconas em filtros solares seguros e eficientes.
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Préparation et dérivatisation de 4H-pyrido[e][1,3]oxazinones : une contribution à la diversité chimique / Preparation and derivatization of 4H-pyrido[e][1,3]oxazinones : a contribution to chemical diversityLe Falher, Laetitia 07 November 2014 (has links)
Ce manuscrit porte sur la synthèse et les applications d'une nouvelle série de composés hétéroaromatiques : les 4H-pyrido[e][1,3]oxazin-4-ones. La première partie de ce manuscrit présente la préparation de ces squelettes via une réaction d'O-arylation intramoléculaire. La seconde partie du manuscrit repose sur la réactivité de ces entités chimiques et de leur utilisation en tant qu'intermédiaires de synthèse. La fonctionnalisation des 4H-pyrido[e][1,3]oxazin-4-ones, via des réactions de couplage pallado-catalysées, a permis d'obtenir des systèmes polyfonctionnalisés plus complexes. Les pyrido-oxazinones ont également été transformées, en une étape, en divers petits hétérocycles d'intérêt : les 1,3,5-triazines, les 1,2,4-triazoles et les 1,2,4-oxadiazoles. La dernière partie du manuscrit est consacrée à l'utilisation des molécules synthétisées comme potentielles sondes fluorescentes pour la détection de protéines oxydées. / This work focused on the synthesis and applications of a novel series of heteroaromaticcompounds: the 4H-pyrido[e][1,3]oxazin-4-ones. The first part of this thesis presents thepreparation of these pyrido-oxazinones via an intramolecular O-arylation reaction. The secondpart of this work relies on the reactivity of these chemical entities and their use as buildingblocks. The functionalization of the 4H-pyrido[e][1,3]oxazin-4-ones has been studied viacross-coupling reactions to obtain more elaborated structures. The pyrido-oxazinones werealso converted, in one step, into other diverse small molecules of interest: 1,3,5-triazines,1,2,4-triazoles and 1,2,4-oxadiazoles. The last part of this thesis was devoted to the use of theobtained heterocycles as potential fluorescent probes for the detection of carbonylatedproteins.
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Conception, synthèse et évaluation biologique de nouveaux ligands sérotoninergiques 5-HT₇ / Design, synthesis and biological evaluation of serotoninergic 5-HT₇ LigandsJouha, Jabrane 18 July 2017 (has links)
Dès la découverte des récepteurs 5-HT₇ en 1993, des études intenses de relation structure-activité ont été poursuivies par plusieurs groupes de recherches, dont notre laboratoire. En conséquence, un nombre impressionnant de ligands potentiels 5-HT₇ sont référencés dans la littérature mais peu sont des agonistes sélectifs. Dans ce contexte, ce travail de thèse a pour but principal, la conception de quatre classes distinctes de ligands et leur évaluation en tant que ligand agoniste des 5-HT₇R. Dans un premier temps, nous nous sommes intéressés à la préparation de ligands de type 2,4-diaminopyrido [2,3-d]pyrimidinique et 2,4-diaminopyrimidinique. Par la suite, nous avons élaboré une troisième famille de composés bâtis sur une charpente pyridinique, à partir d’un des plus intéressants agonistes sélectifs 5-HT₇ actuels et ce, via une stratégie multi-étape efficace. La dernière partie de ce mémoire a été consacrée au développement d’une méthode originale et rapide de synthèse des tétrahydro-1,6-naphtyridines polysubstituées au départ de 3-vinyl-1,2,4-triazines judicieusement fonctionnalisées via une séquence domino d’addition d’aza-Michael et une cyclisation intramoléculaire de Diels-Alder à demande électronique inverse. / Serotonin-activated cell-surface receptor 5-HT₇ is the most recently discovered 5-HT receptor. Intensive studies of structure-activity relationships have been pursued by several research groups, including our laboratory, and have resulted in the publication in the literature of an impressive number of potential ligands 5-HT₇. In this context, the main purpose of this thesis is to design four distinct classes of ligands. First, we were interested in the preparation of 2,4-diaminopyrido[2,3-d]pyrimidinique and 2,4-diaminopyrimidinique ligands. Subsequently, we developed a third family of compounds built on a pyridine scaffold, from one of the most interesting current 5-HT₇ selective agonists, via an effective multistep strategy. The last part of this thesis was devoted to developing an original and rapid method for the synthesis of polysubstituted tetrahydro-1,6-naphthyridines starting from the 3-vinyl-1,2,4-triazines platforms via a domino addition sequence of aza-Michael and intramolecular inverse-electron-demand Diels-Alder cyclization.
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Conception, synthèse et caractérisation de molécules polyhétérocycliques azotées pour la complexation spécifique de cations métalliques / Creation, synthesis and characterisation of nitrogenous polyheterocyclic new molecules for specific complexation of metallic cationsDupont, Carine 10 December 2010 (has links)
La loi du 6 juin 2006 sur la gestion des déchets radioactifs de haute activité et à vie longue prévoit la recherche de solutions permettant la séparation et la transmutation des radioéléments à vie longue, pour réduire les quantités et la nocivité des déchets radioactifs ultimes. Ces déchets issus du retraitement du combustible nucléaire usé sont actuellement vitrifiés à La Hague. Ainsi, le projet « séparation poussée » vise à compléter le procédé industriel PUREX par le développement de procédés permettant d’extraire les actinides mineurs des raffinats PUREX où se trouvent également des produits de fission constitués principalement de lanthanides, neutrophages. Pour réaliser la séparation poussée, les actinides mineurs des raffinats PUREX doivent être séparés par des molécules spécifiques. Les BTP ou bis-triazinyl-pyridines ont été largement étudiées au CEA pour la séparation actinides(III)/lanthanides(III). Elles complexent sélectivement les actinides, mais l'origine de cette sélectivité n'est pas complètement expliquée : notamment l’influence des groupements (attachés à leur structure) sur la complexation ou la sélectivité reste à démontrer. En outre, elles sont sensibles à l'hydrolyse et à la radiolyse. La première partie du travail présente la synthèse de BTP ou de BTBP, différemment substituées pour améliorer leur résistance face à l'hydrolyse ou à la radiolyse, et une nouvelle famille de ligands polyaromatiques azotés : les BPBT, présentant un enchaînement original de cycles pyridine et triazine, différent de toutes les structures décrites jusqu'à présent dans la littérature. La seconde partie de ce travail est consacrée à l’étude physico-chimique de nouvelles molécules obtenues, en déterminant leurs constantes de protonation et de complexation, pour connaître l’influence des différents groupements sur la complexation et la sélectivité. Enfin, le troisième volet concerne l’étude des propriétés de ces ligands en extraction liquide-liquide, utilisés soit comme extractants lipophiles, soit comme complexants hydrophiles. / In France, the nuclear waste issued from the industrial reprocessing of spent nuclear fuels (by the PUREX process) are currently vitrified at the La Hague plant, waiting for a final disposal in a deep geological repository. The law voted in June 2006 on the management of highly active nuclear waste plans to look for solutions enabling the separation and transmutation of long-lived radionuclides so as to reduce the quantity and noxiousness of the final nuclear waste. To address this issue, the CEA investigates and elaborates advanced separation processes based on specially designed complexing or extracting molecules to selectively extract minor actinides from PUREX raffinates containing fission products like lanthanides, which are neutron scavengers. BTP or bis-triazinyl-pyridines have been extensively studied at the CEA (and in Europe) for actinides(III)/lanthanides(III) separation. They complex actinides(III) selectively. However, they are sensitive to degradation by hydrolysis and radiolysis. Besides, their separation mechanisms are not well understood, especially the influence of their substituting groups on their complexing and extracting properties. The first part of work reports the syntheses of various BTP and BTBP molecules, differently substituted, as well as a new family of polyaromatic nitrogen-contained ligands: BPBT, presenting a pyridine/triazine sequence that has never been reported in the literature. The second part is devoted to the physico-chemistry studies of the synthesized molecules, such as the determination of their protonation and complexation constants to describe the influence of different substituting groups. Finally, the last part outlines solvent extraction studies by using these ligands either like extractants or like compexants.
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Příprava a studium nových krystalických materiálů pro nelineární optiku odvozených od dusíkatých heterocyklů / Preparation and study of novel crystalline materials for nonlinear optics based on nitrogen-containing heterocyclesKloda, Matouš January 2019 (has links)
The presented Ph.D. thesis is aimed at the preparation and characterisation of novel crystalline materials with application potential in nonlinear optics (NLO). The main goal was preparation of crystalline salts and adducts (cocrystals) of selected nitrogen-containing heterocycles with a range of organic and inorganic acids. Based on previous study and quantum- chemical calculations, the following starting heterocycles were selected: 2-aminopyrimidine, 4-aminopyrimidine, 5-aminopyrimidine, 3-amino-1,2,4-triazine and 3-amino-5,6-dimethyl- 1,2,4-triazine. The prepared materials were characterised mainly by X-ray diffraction and vibrational spectroscopy and the interpretation of the vibrational spectra was based on quantum-chemical calculations. The systems based on aminopyrimidines were the first field of study in presented thesis. The thesis represents a finalisation of our previous study focused on inorganic salts and cocrystal in the case of 2-aminopyrimidine. The characterisation of a pair of cocrystals with boric acid was accomplished. The 12 new salts and adducts were prepared and characterised in the case of 4-aminopyrimidine and only one crystalline product - adduct with succinic acid - was obtained in the case of 5-aminopyrimidine. The systems based on 3-amino-1,2,4-triazine and its...
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Synthetic strategies for potential trypanocidesCapes, Amy January 2011 (has links)
Human African trypanosomiasis (sleeping sickness) is a devastating disease which is endemic in parts of sub-Saharan Africa. It is caused by the protozoan parasite T. brucei, which are transmitted by the bite of infected tsetse flies. Although the disease is fatal if left untreated, there is a lack of safe, effective and affordable drugs available; therefore new drugs are urgently needed. The aim of the work presented in this thesis is to develop novel trypanocidal compounds. It is divided into two parts to reflect the two distinct strategies employed to achieve this aim. The first part focuses on the inhibition of glycophosphoinositol (GPI) anchor synthesis by inhibiting the Zn2+-dependent enzyme, GlcNAc-PI de-N-acetylase. Trypanosomes have a variable surface glycoprotein (VSG) coat, which allows them to evade the human immune system. The GPI anchor attaches the VSG to the cell membrane; therefore inhibiting GPI synthesis should expose the parasite to the immune system. Initially, large substrate analogues were synthesized. These showed weak inhibition of the enzyme. Zinc-binding fragments were screened, and small molecule inhibitors based on salicylhydroxamic acid were then synthesized. These compounds showed modest inhibition, but the excellent ligand efficiency of salicylhydroxamic acid indicates this may be a promising starting point for further inhibitors. The second part details the P2 strategy. The P2 transporter is a nucleoside transporter unique to T. brucei, which concentrates adenosine. The transporter also binds and selectively concentrates compounds that contain benzamidine and diaminotriazine P2 motifs, which can enhance the potency and selectivity of these compounds. The sleeping sickness drugs melarsoprol and pentamidine contain P2 motifs. Compounds comprising a P2 targeting motif, a linker and a trypanocidal moiety were synthesized. Initially, a diaminotriazine P2 motif was attached to a trypanocidal tetrahydroquinoline (THQ) protein farnesyl transferase (PFT) inhibitor, with limited success. The P2 strategy was also applied to a non-selective, trypanocidal, quinol moiety. The quinol moiety was attached to diaminotriazine and benzamidine P2 motifs, and an increase in selectivity for T. brucei over MRC5 cells was observed.
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