Dissertations / Theses: 'Imidazo[2'

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Grosse, Sandrine. "Imidazo[1, 2-b]pyrazoles, imidazo[1, 2-a]imidazoles : synthèse, fonctionnalisation et évaluation biologique." Thesis, Orléans, 2013. http://www.theses.fr/2013ORLE2056.

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Les imidazo[1,2-b]pyrazoles tout comme les imidazo[1,2-a]imidazoles sont des entités présentant diverses applications intéressantes notamment dans le domaine pharmacologique. Cependant, malgré ce potentiel, ces structures hétérobicycliques ont été, jusqu’à ce jour, relativement peu étudiées tant au niveau de leur préparation que de leur fonctionnalisation. De ce fait, ces travaux de thèse ont pour objet la mise au point de nouvelles voies d’accès à ces systèmes bicycliques et ce, au départ de substrats facilement accessibles. Des stratégies de fonctionnalisation de ces charpentes moléculaires ont ensuite été développées dans le but de concevoir des librairies diversifiées de ce type de composés, librairies destinées à être évaluées biologiquement. Les premiers résultats d’évaluation sur des lignées cancéreuses de dérivés imidazo[1,2-b]pyrazoliques sont également présentés
Imidazo[1,2-b]pyrazoles and imidazo[1,2-a]imidazoles are entities with some interesting applications in pharmacology. However, despite this potential, few methods of preparation and direct functionalisation of the heterocyclic moiety have been described. In this context, the overall goal of our research is to develop new routes to these bicyclic systems from readily available starting materials. Strategies of functionalisation of the heterocyclic moiety were then explored in order to design diversified libraries for the evaluation of potential biological activities. Herein, the results of the tests of imidazo[1,2-b]pyrazole series against various cancer lines are reported

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2

Juškėnas, Robertas. "Synthesis of tricyclic heterosystems based on pyrazolo[3,4-d]pyrimidine framework. Study of intramolecular reaction of pyrimidine nitrogen atom with O,O-acetals." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140630_154044-28576.

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The development of heterocyclic chemistry is important for various science areas and for the industry. The main task of this branch of chemistry is the search for the new, more effective synthetic methods for obtaining heterocyclic derivatives. That covers not only the formation of heterocycles, but also their functionalization, which leads to the creation of compounds having various chemical and physical properties. The accomplishments of this area are applied in biochemistry, pharmacochemistry, photophysics and other branches of science and industry. The creation of effective heterocycles synthesis methods, that may be applied for the formation of heterosystems based on pyrazolo[3,4-d]pyrimidine was the main aim in this work. During this work, three hitherto unknown peri-fused heterocyclic systems based on pyrazolo[3,4-d]pyrimidine scaffold were synthesized. The suitable conditions for the cyclization of 4-(2,2-diethoxyethyl)aminopyrimidines to 2,3-dihydroimidazo[1,2-c]pyrimidines were found. The influence of functional groups in pyrimidine moiety for the course of this reaction was investigated. It has been shown that functional groups including alkylthio, cyano, amino, formyl are tolerated in this type of reaction. The method for the replacement of ethoxy group with benzyl mercaptan in 3-ethoxy-2,3-dihydroimidazo[1,2-c]pyrazolo[4,3-e]pyrimidines has been found.
Heterociklų chemijos vystymasis turi didelę reikšmę įvairioms mokslo sritims ir pramonės raidai. Pagrindinis šios chemijos srities uždavinys – kurti naujus heterociklinių junginių sintezės metodus, leidžiančius paprasčiau, efektyviau gauti norimos struktūros junginius. Tai apima ne tik heterociklų formavimo būdus, bet ir jų funkcionalizavimą, leidžiantį sukurti įvairiomis cheminėmis ir fizikinėmis savybėmis pasižyminčių junginių įvairovę. Šios mokslo srities pasiekimai pritaikomi biochemijoje, farmacijoje, fotofizikoje ir kitose mokslo ir pramonės šakose. Šiame darbe buvo siekiama sukurti efektyvius heterosistemų sintezės būdus, kuriuos galima pritaikyti pirazolo[3,4-d]pirimidino fragmentą turinčių heterociklų formavimui. Šio darbo metu buvo susintetintos trys iki šiol neaprašytos heterociklinės sistemos atliekant peri-kondensuotų heterosistemų sintezę iš 3-amino-4-chlor-1-metil-6-metiltio-1H-pirazolo[3,4-d]pirimidino. Surastos tinkamos sąlygos 4-(2,2-dietoksietilmino)pirimidinų ciklizacijai į 3-etoksi-2,3-dihidroimidazo[1,2-c]pirimidinus. Ištirta pirimidino žiede esančių pakaitų įtaka šiai reakcijai. Parodyta, kad ši reakcija yra suderinama su tokiomis funkcinėmis grupėmis, kaip alkiltio-, cian-, amino-, formilgrupės. Surastas metodas 3-etoksi-2,3-dihidroimidazo[1,2-c]pirazolo[4,3-e]pirimidinų etoksigrupės pakeitimui benziltiogrupe.

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Juškėnas, Robertas. "Triciklių heterosistemų, turinčių pirazolo[3,4-d]pirimidino fragmentą, sintezė. Intramolekulinės pirimidino azoto atomo reakcijos su O,O-acetaliais tyrimas." Doctoral thesis, Lithuanian Academic Libraries Network (LABT), 2014. http://vddb.library.lt/obj/LT-eLABa-0001:E.02~2014~D_20140630_154058-49723.

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Heterociklų chemijos vystymasis turi didelę reikšmę įvairioms mokslo sritims ir pramonės raidai. Pagrindinis šios chemijos srities uždavinys – kurti naujus heterociklinių junginių sintezės metodus, leidžiančius paprasčiau, efektyviau gauti norimos struktūros junginius. Tai apima ne tik heterociklų formavimo būdus, bet ir jų funkcionalizavimą, leidžiantį sukurti įvairiomis cheminėmis ir fizikinėmis savybėmis pasižyminčių junginių įvairovę. Šios mokslo srities pasiekimai pritaikomi biochemijoje, farmacijoje, fotofizikoje ir kitose mokslo ir pramonės šakose. Šiame darbe buvo siekiama sukurti efektyvius heterosistemų sintezės būdus, kuriuos galima pritaikyti pirazolo[3,4-d]pirimidino fragmentą turinčių heterociklų formavimui. Šio darbo metu buvo susintetintos trys iki šiol neaprašytos heterociklinės sistemos atliekant peri-kondensuotų heterosistemų sintezę iš 3-amino-4-chlor-1-metil-6-metiltio-1H-pirazolo[3,4-d]pirimidino. Surastos tinkamos sąlygos 4-(2,2-dietoksietilmino)pirimidinų ciklizacijai į 3-etoksi-2,3-dihidroimidazo[1,2-c]pirimidinus. Ištirta pirimidino žiede esančių pakaitų įtaka šiai reakcijai. Parodyta, kad ši reakcija yra suderinama su tokiomis funkcinėmis grupėmis, kaip alkiltio-, cian-, amino-, formilgrupės. Surastas metodas 3-etoksi-2,3-dihidroimidazo[1,2-c]pirazolo[4,3-e]pirimidinų etoksigrupės pakeitimui benziltiogrupe.
The development of heterocyclic chemistry is important for various science areas and for the industry. The main task of this branch of chemistry is the search for the new, more effective synthetic methods for obtaining heterocyclic derivatives. That covers not only the formation of heterocycles, but also their functionalization, which leads to the creation of compounds having various chemical and physical properties. The accomplishments of this area are applied in biochemistry, pharmacochemistry, photophysics and other branches of science and industry. The creation of effective heterocycles synthesis methods, that may be applied for the formation of heterosystems based on pyrazolo[3,4-d]pyrimidine was the main aim in this work. During this work, three hitherto unknown peri-fused heterocyclic systems based on pyrazolo[3,4-d]pyrimidine scaffold were synthesized. The suitable conditions for the cyclization of 4-(2,2-diethoxyethyl)aminopyrimidines to 2,3-dihydroimidazo[1,2-c]pyrimidines were found. The influence of functional groups in pyrimidine moiety for the course of this reaction was investigated. It has been shown that functional groups including alkylthio, cyano, amino, formyl are tolerated in this type of reaction. The method for the replacement of ethoxy group with benzyl mercaptan in 3-ethoxy-2,3-dihydroimidazo[1,2-c]pyrazolo[4,3-e]pyrimidines has been found.

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4

Tber, Zahira. "L'imidazo[1,2-a]pyridine : fonctionnalisation et synthèse des nouveaux polyhétérocycles." Thesis, Orléans, 2016. http://www.theses.fr/2016ORLE2021.

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Les préparations de composés comportant un noyau imidazo[1,2-a]pyridinique constituent un thème de recherche important en synthèse organique, compte tenu des nombreuses activités biologiques qu’ils peuvent présenter. Dans la première partie, nous nous sommes concentrés sur le développement de nouvelles stratégies rapides et efficaces basées sur l’utilisation de cuivre et de fer pour fonctionnaliser la position 6 du cycle imidazo[1,2-a]pyridine avec diverses amines et divers thiols. Ensuite, nous avons appliqué avec succès cette procédure pour la préparation de thioéthers symétriques et dissymétriques en utilisant le 2-mercaptobenzooxasole, réactif économique qui ne présente aucun risque chimique. Dans le dernier volet de ce travail, nous nous sommes intéressés au développement de nouvelles réactions multicomposants en vue de synthétiser divers pyrrolo[3',2':4,5]imidazo[1,2-a]pyridines et 5-aminopyrido[2’,1’:2,3]imidazo[4,5-c]isoquinoléines
The preparations of imidazo[1,2-a]pyridine is one of important research topic in organic synthesis, This entitie present some interesting biological activities. First, we devoleped a new rapid and efficient strategies to functionalize position 6 of the imidazo[1,2-a]pyridine with various amines and thiols catalysed by copper and iron. Then we applied this procedure to the preparation of symmetric and asymmetric thioethers using 2 mercaptobenzooxasole, which is an economical reagent and which presents no chemical risk. The last part of this work concerns the development of new multicomponent reactions for the synthesis of various pyrrolo[3',2':4,5]imidazo[1,2-a]pyridine and 5-amino pyrido[2’,1’:2,3] imidazo [4,5-c]isoquinoléines

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5

El, Akkaoui Ahmed. "Synthèse et réactivité d'imidazo[1,2-x]azines : obtention de composés polycycliques." Phd thesis, Université d'Orléans, 2009. http://tel.archives-ouvertes.fr/tel-00497002.

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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 imidazo[1,2-x]azines. Dans la première partie, nous avons étudié la sélectivité des couplages de type Suzuki et Sonogashira au départ de 3,6-dihalogénoimidazo[1,2-a]pyridines. Par la suite, cette méthodologie a été appliquée aux imidazo[1,2-b]pyridazines pour l'obtention de divers composés di- et trisubstitués. Afin de réduire le nombre d'étapes, nous avons étudié les réactions d'(hétéro)arylation directes catalysées soit par le palladium soit par le cuivre sur les imidazo[1,2-b]pyridazines. Nous avons ensuite montré l'intérêt de ces réactions lors de la synthèse d'imidazo[1,2-b]pyridazines polysubstituées, via une procédure "one-pot" et ce, sous irradiation micro-ondes. Dans le dernier volet de ce travail, nous nous sommes concentrés sur le développement de nouvelles réactions multicomposant en vue de synthétiser divers azino[1',2':1,2]imidazo[5,4-b]indoles, pyrido[2',1':1,2]imidazo[5,4-c]isoquinoléin-5-ones et pyrido[2',1':1,2]imidazo[5,4-c] isoquinoléines.

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Elie, Jonathan. "Développement de médicaments radiopharmaceutiques fluorés pour l'exploration en imagerie moléculaire TEP de la neuroinflammation." Thesis, Tours, 2016. http://www.theses.fr/2016TOUR3302.

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Les maladies du système nerveux central (SNC) comme la sclérose en plaques, les accidents vasculaires cérébraux et les maladies neurodégénératives (Alzheimer et Parkinson) entraînent une réponse inflammatoire au niveau cérébrale appelée neuroinflammation. Ce phénomène peut avoir pour conséquence la limitation de la propagation de la maladie mais aussi la réparation et la régénération des tissus touchés. La microglie, principale défense du SNC, passe à un stade activé lors de phénomènes neuroinflammatoires et va libérer de nombreux facteurs neuroprotecteurs mais aussi pro-inflammatoires. Cette dualité d’action va ainsi maintenir un cercle vicieux, pouvant conduire à la mort neuronale. Il serait donc intéressant de comprendre le mécanisme de la neuroinflammation pour diagnostiquer et traiter au mieux les pathologies du SNC. Il existe plusieurs cibles moléculaires, parmi elles se trouvent la CycloOXygénase 2 (COX-2), une enzyme qui permet la formation de prostaglandines à partir de l'acide arachidonique, qui apparaît précocement et est fortement surexprimée en cas de neuroinflammation. Cette enzyme serait donc une cible de choix pour le développement d’outils d’imagerie dans le but de diagnostiquer les pathologies dans lesquelles les processus inflammatoires centraux sont présents et ce afin d’améliorer la prise en charge du patient. La tomographie d’émission de positons (TEP) est une technique d’imagerie fonctionnelle très sensible qui permet de quantifier de manière fine les variations d’activités métaboliques ou moléculaires. Cette technique requiert l’utilisation de radiotraceurs marqués avec un émetteur béta+
Central nervous system (CNS) disorders as multiple sclerosis, stroke and neurodegenerative diseases (Alzheimer’s and Parkinson’s) lead to inflammatory response in the brain called neuroinflammation. This phenomenon usually should result in limiting the spread of the disease but also repair and regeneration of the affected tissues. Microglia, the main defense of the SNC, which is activated during a neurodegenerative event leading to the production of many factors including neuroprotectors but also pro-inflammatories. This duality of actions will thereby maintain endless vicious circle leading to neuronal death. It would be interesting to understand the neuroinflammation mechanism to better diagnose and treat CNS diseases. There are several molecular targets, among them are the CycloOXygenase 2 (COX-2), an enzyme which allows the formation of prostaglandins from arachidonic acid, which appears early and it is significantly overexpressed in case of neuroinflammation. This enzyme is therefore a good biological target for the development of imaging tools in order to diagnose pathologies in which central inflammatory processes are present in order to improve patient care. Postiron emission tomography (PET) is a very sensitive functional imaging technique that quantifies minute variations in metabolic or molecular activities. This technique requires the use of radiotracers labeled with a beta + emitter

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Dembele, Ousmane. "Design, synthèse et étude biologique de dérivés à structure imidazo[4,5-c]-1,6-naphtyridin-2(1H)-one et analogues structuraux à visée antiproliférative." Thesis, Nantes, 2018. http://www.theses.fr/2018NANT4004.

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La protéine kinase constitue une cible prometteuse pour le traitement de nombreuses pathologies cancéreuses. Enzymes réalisant la phosphorylation des protéines en transférant un groupement phosphate de l’ATP vers une protéine substrat. Cette dernière effectue alors un changement conformationnel qui lui confère de nouvelles fonctions. Si leur action s’effectue sur un acide aminé phénolique, on parlera de tyrosine kinase (TK) mais si elle s’effectue sur un acide aminé alcoolique non-aromatique, on parlera de sérine/thréonine kinase (STK). L’inhibition de son activité représente un enjeu important dans la découverte de nouvelles molécules anticancéreuses grâce notamment à la connaissance de leur organisation structurale. L’idée d’origine était de prendre appui sur une structure d’origine marine pour développer un travail de « drug discovery ». Il a été choisi de partir de la structure des grossularines A et B extraites d’un tunicier marin (Dendrodoa grossularia) comme modèle puisque nous avions de l’antériorité dans les travaux sur ce type de structure. Ceci a permis d’envisager de mettre au point des analogues et/ou dérivés de ces grossularines, avec, en série pyridazinoindole, l’identification de hits sur PI3K ou DYRK1A. Notre travail porte sur la synthèse de nouvelles molécules originales en série imidazo-naphtyridinones et analogues structuraux potentiellement inhibitrices des Kinases. Les composés synthétisés ont été évalués en parallèle par la Station Biologique de Roscoff sur un panel de kinases (HASPIN, CLK1, DYRK1A, CDK5, CDK9, et GSK3α/β et CK1)
Protein kinase is a promising target for the treatment of many cancer pathologies. Enzymes effecting phosphorylation of proteins by transferring a phosphate group of ATP to a substrate protein. The latter then makes a conformational change that gives it new functions. If their action is performed on a phenolic amino acid, it will be called tyrosine kinase (TK) but if it is performed on a non-aromatic alcoholic amino acid, it will be called serine / threonine kinase (STK). The inhibition of its activity represents an important stake in the discovery of new anticancer molecules, thanks in particular to the knowledge of their structural organization. The original idea was to build on a marine-based structure to develop a drug discovery work. It was chosen from the structure of the grossularines A and B extracted from a marine tunicate (Dendrodoa grossularia) as a model since we had anteriority in the work on this type of structure. This made it possible to envisage the development of analogues and / or derivatives of these grossularins, with, in series pyridazinoindole, the identification of hits on PI3K or DYRK1A. Our work focuses on the synthesis of new original imidazo-naphthyridinone series molecules and structural analogues potentially inhibitory to kinases. The synthesized compounds were evaluated in parallel by the Roscoff Biological Station on a panel of kinases (HASPIN, CLK1, DYRK1A, CDK5, CDK9, and GSK3α/β and CK1)

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Griffon, Du Bellay Amaury. "Synthèse de ligands du récepteu de l'Urotensine II et des récepteurs de la Mélatonine. Composés à noyau pyrido[2,3-d]pyrimidine ou imidazo[1,2-a]pyridine." Phd thesis, Université d'Orléans, 2008. http://tel.archives-ouvertes.fr/tel-00418219.

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L'Urotensine II est un peptide vasoactif que l'on retrouve chez toutes les espèces étudiées. Elle présente une partie N-terminale linéaire variable selon l'espèce et une partie C-terminale hexocyclique constante et responsable de l'activité. Parmi les ligands développés, le Palosuran, un inhibiteur sélectif du récepteur de l'Urotensine II, présente un intérêt dans le traitement de l'insuffisance rénale du patient diabétique voire dans certaines pathologies ischémiques. Dans la première partie de ce travail de thèse, une série de composés à noyau pyrido[2,3-d]pyrimidine a été développée, tout d'abord, par analogie aux structures brevetées par Takeda puis sur le modèle du Palosuran.
La Mélatonine est une hormone à noyau indolique produite pendant la nuit par la glande pinéale et qui présente de nombreuses propriétés dont la plus importante est la synchronisation de l'horloge biologique avec le cycle jour-nuit. L'Agomélatine, analogue mélatoninergique à noyau naphtalénique développé par les Laboratoires Servier pour le traitement de la dépression, est un agoniste des récepteurs MT1 et MT2 et un antagoniste du récepteur 5HT2c. C'est sur ce modèle, qu'ont été développés des ligands à noyau pyrido[2,3-d]pyrimidine par substitution des sommets 2, 4 et 6, soit par alkylation, soit par couplages palladiés. La ramification de la chaîne latérale de l'Agomélatine ayant conduit à des composés actifs, il a été envisagé la synthèse d'analogues possédant la même chaîne en série pyrido[2,3-d]pyrimidine d'une part puis imidazo[1,2-a]pyridine d'autre part.

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Copin, Chloé. "Exploration moléculaire en série imidazo[2, 1-b][1, 3, 4]thiadiazole : applications à la synthèse d'inhibiteurs de kinases impliqués dans les maladies neurodégénératives." Thesis, Orléans, 2013. http://www.theses.fr/2013ORLE2074.

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Depuis plus d’un siècle, la chimie hétérocyclique représente l’un des plus vastes domaines de recherche en chimie organique. En particulier, les hétérocycles bicycliques fusionnés à 5 chaînons, contenant à la fois des atomes de soufre et d’azote, présentent, de par leur rareté et leur potentiel biologique, un champ d’intérêt croissant pour les équipes de recherche et développement académiques ou des entreprises pharmaceutiques. Parmi les nombreux composés bicycliques [5-5], notre étude s’est focalisée sur le noyau imidazo[2,1-b][1,3,4]thiadiazole décrit sporadiquement dans la littérature et pour lequel les voies d’accès actuelles ne se limitent qu’à une seule méthode faisant intervenir une étape de cyclisation et des conditions drastiques. Ce verrou entraine inéluctablement une faible diversité fonctionnelle autour de cet hétérocycle, restreignant ainsi les domaines d’applications notamment biologiques. Afin de pallier à cette problématique, nous avons initié une étude de la réactivité de chacune des trois positions fonctionnalisables du bicycle imidazo[2,1-b][1,3,4]thiadiazole, développant ainsi diverses réactions pallado-catalysées (Suzuki-Miyaura, CH-arylation, Buchwald-Hartwig), de substitution nucléophile aromatique et de Pictet-Spengler. L’étude des propriétés biologiques des différents composés synthétisés et hautement valorisables durant ces travaux a abouti à la découverte de deux séries de molécules inhibant sélectivement les kinases DYRK-1A et CLK-1, deux protéines d’intérêt dans le traitement des affections du système nerveux central (neuropathies, Alzheimer…)
For more than a century, heterocyclic chemistry is one of the largest area in organic chemistry research. In particular, because of their rarity and their biological potential, [5-5] fused ring heterocycles containing both sulfur and nitrogen atoms are a large area of interest for both academic and industrial research and development teams. Among these numerous [5-5] bicycles, our study is focused on imidazo[2,1-b][1,3,4]thiadiazole scaffold, which is quite few described in the literature and whose pathways are limited to almost one method involving a cyclisation step and drastic conditions. This lock leads inevitably to low functional diversity around this heterocycle, thus restricting its applications, including biological. In order to overcome this problematic, we then initiated the reactivity study of each three positions of the bicycle imidazo[2,1-b][1,3,4]thiadiazole, developing thereby several palladium couplings (Suzuki-Miyaura, direct arylation, Buchwald-Hartwig), as well as aromatic nucleophilic substitution and Pictet-Spengler reaction. The study of the biological properties of the different compounds synthesized in this work and highly valuable led to the discovery of two series of molecules, inhibiting selectively DYRK-1A and CLK-1, two kinases of interest in the treatment of dysfunction of central nervous system (neuropathies, Alzheimer…)

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Hallé, François. "Conception, développement et synthèse de ligands du TSPO dans le but de traiter les maladies neurodégénératives." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAF054/document.

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Les neurostéroïdes sont des composés endogènes qui peuvent moduler la transmission synaptique et avoir un effet neuroprotecteur dans les maladies neurodégénératives. Les systèmes régulant leur biosynthèse ne sont pas connus mais la première étape de celle-ci peut être régulée par la protéine TSPO. Cette protéine mitochondriale facilite le transport du cholestérol vers l’intérieur de la mitochondrie pour y être métabolisé en prégnénolone. Ce stéroïde est le précurseur principal de la biosynthèse des neurostéroïdes et l’utilisation in vitro de ligands du TSPO permet d’augmenter sa sécrétion. Dans ce travail de thèse, nous avons ainsi cherché à développer de nouvelles familles de ligands solubles du TSPO augmentant la sécrétion de prégnénolone. Le développement de ces nouvelles familles a nécessité la réalisation d’une méthodologie de synthèse faisant intervenir une réaction de cyclisation pallado-catalysée de type Buchwald-Hartwig. Une étude de solubilité des composés synthétisés a été effectuée expérimentalement, leur activité a été évaluée par des méthodes fonctionnelles et leur effet neuroprotecteur a été testé sur un modèle cellulaire de la maladie d’Alzheimer
Neurosteroids are endogenous compounds which can alter the synaptic transmission and enhance neuroprotection in neurodegenerative diseases. The systems that regulates their biosynthesis are not described but its first step ca be regulated by the TSPO. This mitochondrial protein facilitates the transport of cholesterol to the mitochondrial matrix to be metabolized in pregnenolone. This steroid is the precursor of neurosteroid biosynthesis and in vitro use of TSPO ligands induces its secretion. For this project, we looked forward to develop new families of soluble TSPO ligands that can increase pregnenolone production. The access to 3-amino-3,4-dihydroquinolin-2-ones required the establishment of a synthesis methodology of a palladium-catalyzed cyclization following Buchwald-Hartwig amination. A solubility study of synthesized compound was performed, their activity was established based on functional assays and their neuroprotective effect was evaluated on a cellular model of Alzheimer disease

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Fersing, Cyril. "Synthèse et étude des relations structure-activité de nouvelles 3-nitroimidazo (1,2-a) pyridines anti-kinétoplastidés." Thesis, Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0275/document.

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Les maladies tropicales négligées causées par les protozoaires kinétoplastidés du genre Leishmania et Trypanosoma représentent une menace pour près d’un demi-milliard de personnes en zone intertropicale, entrainant jusqu’à 50 000 décès par an. Parmi les molécules en développement clinique pour traiter ces pathologies, le fexinidazole est une prodrogue appartenant à la famille des 5-nitroimidazoles et qui exerce son action anti-infectieuse via une étape de bioactivation catalysée par des nitroréductases (NTR) parasitaires, enzymes dont le co-facteur est une flavine. Afin d’identifier de nouveaux nitrohétérocycles antiparasitaires substrats des NTR, une petite chimiothèque d’imidazo[1,2-a]pyridines synthétisées au laboratoire a subi un criblage in vitro ayant conduit à l’identification d’une molécule Hit, à la fois active sur Leishmania donovani et Trypanosoma brucei brucei. Ce composé a servi de point de départ à un travail de pharmacomodulation, dans un premier temps en position 8 du cycle imidazo[1,2-a]pyridine : l’introduction de groupements variés à l’aide de réactions de couplage pallado-catalysées de Suzuki-Miyaura, Sonogashira et Buchwald-Hartwig ou des réactions de SNAr, a permis de mettre en lumière plusieurs composés « tête de série » au profil biologique nettement amélioré. Dans un second temps, le travail de pharmacomodulation entrepris a été étendu aux positions 2, 3 et 6 du cycle imidazo[1,2-a]pyridine en vue de compléter les données de relations structure-activité, d’étudier en particulier l’impact du potentiel rédox et d’optimiser les paramètres physico-chimiques et pharmacocinétiques in vitro des meilleurs composés
The kinetoplastids of the Leishmania and Trypanosoma genus are the causative agents of neglected tropical diseases that threaten nearly half a billion people in the intertropical zone, resulting in 50 000 deaths per year. Among the molecules in clinical development to treat these pathologies, fexinidazole is a prodrug belonging to the 5-nitroimidazoles family, which exerts its anti-infectious action via a bioactivation step catalyzed by parasitic nitroreductases (NTR), enzymes whose cofactor is a flavin. In order to identify novel nitroheterocycles as parasitic NTR substrates, a small chemical library of imidazo[1,2-a]pyridines synthesized by our laboratory was screened in vitro, leading to the identification of a Hit molecule active both on Leishmania donovani and Trypanosoma brucei brucei. This compound served as a starting point for a pharmacomodulation work, initially in position 8 of the imidazo[1,2-a]pyridine ring: the introduction of various chemical groups using the pallado-catalyzed coupling reactions of Suzuki-Miyaura, Sonogashira and Buchwald-Hartwig, or SNAr reactions, highlighted several "lead" compounds with a significantly improved biological profile. In a second step, the pharmacomodulation work was extended to positions 2, 3 and 6 of the imidazo[1,2-a]pyridine ring in order to complete the structure-activity relationship data, to study in particular the impact of the redox potential and to optimize the physicochemical and in vitro pharmacokinetic parameters of the best compounds in order to initiate the study of their in vivo activity on a trypanosomiasis mouse model

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12

Mao, Zhongyi. "Stereodivergent and enantioselective total syntheses of chaetominine-type alkaloids and azaphilic radical cascade cyclization for the synthesis of imidazo-fused heteroaromatics and toward analogs of the 2-Carboxyl-6-HydroxyOctahydroIndole (CHOI) Unit." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066449/document.

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Les composés azotés ont un grand intérêt car cet élément se retrouve dans la plupart des produits naturels et pharmaceutiques, de sorte que le développement de méthodes efficaces pour leur préparation est hautement souhaitable. Tout d'abord, une méthode stéréodivergente et énantiosélective a été développée pour la synthèse totale des alcaloïdes de type chaetominine, y compris les structures proposées de la (-)-pseudofischerine, de l’(-)-aniquinazoline D et de l’(-)-isochaetominine, de l’(-)-isochaetominines A-C, de la (+)-14-epi-isochaetominine C, ainsi que les quatre stéréoisomères jusqu'ici inconnus de l'isochaetominine C. A la lumière de nos travaux de synthèse, les structures de la (-)-pseudofischerine naturelle et l’(-)-aniquinazoline D ont été révisées comme l’(-)-isochaetominine C, et la structure de l’(-)-isochaetominine naturelle a été révisée comme la (-)-11-epi-chaetominine. Ensuite, une réaction de cyclisation en cascade de radicaux azaphiles a été développée conduisant à une synthèse efficace d'hétéroaromatiques de type imidazo-accolés à partir de carbamates N-hétéroaryl-O-propargyliques facilement disponibles. La synthèse électrochimique organocatalysée est généralisable, tolère de nombreux groupes fonctionnels, et se déroule dans des conditions douces sans besoin de catalyse par les métaux de transition, ni d'oxydants. Enfin, deux approches à des analogues de l'unité CHOI ont été développées. Les étapes clés de la de synthèse sont basées sur la C-allylation et la N-allylation palladocatalysées, qui permettent la transformation d’un substrat bis-allylique cyclique en un hexahydroindole. En fonction de la stratégie appliquée, la position de la fonction alcène de l'hexahydroindole peut se retrouver sur des positions différentes du squelette. L’homologation d’un atome de carbone suivie d'une époxydation ou d'une syn-dihydroxylation des intermédiaires bicycliques résultants fournissent les analogues CHOI désirés
Nitrogen-containing compounds have a great interest as this element is found in natural products and drugs, thus the development of efficient methods for their preparation is highly desirable. First, a stereodivergent and enantioselective method has been developed for the total syntheses of chaetominine-type alkaloids including the proposed structures of (-)-pseudofischerine, (-)-aniquinazoline D and (-)-isochaetominine, (-)-isochaetominines A–C, (+)-14-epi-isochaetominine C, as well as the four hitherto unknown stereoisomers of isochaetominine C. The structures of natural (-)-pseudofischerine and (-)-aniquinazoline D have been revised as (-)-isochaetominine C and the structure of the natural (-)-isochaetominine have been revised to (-)-11-epi-chaetominine based on our synthetic efforts. Next, an azaphilic radical cascade cyclization reaction has been developed leading to the efficient synthesis of imidazo-fused heteroaromatics from easily available N-heteroaryl-O-propargyl carbamates. The organocatalyzed electrochemical synthesis has a broad scope, tolerates many common functional groups, and proceeds under mild conditions without the need of transition-metal catalysis or chemical oxidant. Finally, two approaches toward analogs of the CHOI unit have been developed. The key steps of the synthetic route were based on Pd-catalyzed C-allylation and N-allylation, which converted a cyclic bis-allylic substrate into a hexahydroindole scaffold. Depending on the strategy applied, the position of alkene moiety of the resulting hexahydroindole can be obtained at different positions. One-carbon homologation followed by epoxidation or syn-dihydroxylation of the resulting bicyclic intermediates afforded the desired CHOI analogues

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Fersing, Cyril. "Synthèse et étude des relations structure-activité de nouvelles 3-nitroimidazo (1,2-a) pyridines anti-kinétoplastidés." Electronic Thesis or Diss., Aix-Marseille, 2018. http://www.theses.fr/2018AIXM0275.

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Les maladies tropicales négligées causées par les protozoaires kinétoplastidés du genre Leishmania et Trypanosoma représentent une menace pour près d’un demi-milliard de personnes en zone intertropicale, entrainant jusqu’à 50 000 décès par an. Parmi les molécules en développement clinique pour traiter ces pathologies, le fexinidazole est une prodrogue appartenant à la famille des 5-nitroimidazoles et qui exerce son action anti-infectieuse via une étape de bioactivation catalysée par des nitroréductases (NTR) parasitaires, enzymes dont le co-facteur est une flavine. Afin d’identifier de nouveaux nitrohétérocycles antiparasitaires substrats des NTR, une petite chimiothèque d’imidazo[1,2-a]pyridines synthétisées au laboratoire a subi un criblage in vitro ayant conduit à l’identification d’une molécule Hit, à la fois active sur Leishmania donovani et Trypanosoma brucei brucei. Ce composé a servi de point de départ à un travail de pharmacomodulation, dans un premier temps en position 8 du cycle imidazo[1,2-a]pyridine : l’introduction de groupements variés à l’aide de réactions de couplage pallado-catalysées de Suzuki-Miyaura, Sonogashira et Buchwald-Hartwig ou des réactions de SNAr, a permis de mettre en lumière plusieurs composés « tête de série » au profil biologique nettement amélioré. Dans un second temps, le travail de pharmacomodulation entrepris a été étendu aux positions 2, 3 et 6 du cycle imidazo[1,2-a]pyridine en vue de compléter les données de relations structure-activité, d’étudier en particulier l’impact du potentiel rédox et d’optimiser les paramètres physico-chimiques et pharmacocinétiques in vitro des meilleurs composés
The kinetoplastids of the Leishmania and Trypanosoma genus are the causative agents of neglected tropical diseases that threaten nearly half a billion people in the intertropical zone, resulting in 50 000 deaths per year. Among the molecules in clinical development to treat these pathologies, fexinidazole is a prodrug belonging to the 5-nitroimidazoles family, which exerts its anti-infectious action via a bioactivation step catalyzed by parasitic nitroreductases (NTR), enzymes whose cofactor is a flavin. In order to identify novel nitroheterocycles as parasitic NTR substrates, a small chemical library of imidazo[1,2-a]pyridines synthesized by our laboratory was screened in vitro, leading to the identification of a Hit molecule active both on Leishmania donovani and Trypanosoma brucei brucei. This compound served as a starting point for a pharmacomodulation work, initially in position 8 of the imidazo[1,2-a]pyridine ring: the introduction of various chemical groups using the pallado-catalyzed coupling reactions of Suzuki-Miyaura, Sonogashira and Buchwald-Hartwig, or SNAr reactions, highlighted several "lead" compounds with a significantly improved biological profile. In a second step, the pharmacomodulation work was extended to positions 2, 3 and 6 of the imidazo[1,2-a]pyridine ring in order to complete the structure-activity relationship data, to study in particular the impact of the redox potential and to optimize the physicochemical and in vitro pharmacokinetic parameters of the best compounds in order to initiate the study of their in vivo activity on a trypanosomiasis mouse model

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Nordqvist, Anneli. "Hit Identification and Hit Expansion in Antituberculosis Drug Discovery : Design and Synthesis of Glutamine Synthetase and 1-Deoxy-D-Xylulose-5-Phosphate Reductoisomerase Inhibitors." Doctoral thesis, Uppsala universitet, Avdelningen för organisk farmaceutisk kemi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-155428.

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Since the discovery of Mycobacterium tuberculosis (Mtb) as the bacterial agent causing tuberculosis, the permanent eradication of this disease has proven challenging. Although a number of drugs exist for the treatment of tuberculosis, 1.7 million people still die every year from this infection. The current treatment regimen involves lengthy combination therapy with four different drugs in an effort to combat the development of resistance. However, multidrug-resistant and extensively drug-resistant strains are emerging in all parts of the world. Therefore, new drugs effective in the treatment of tuberculosis are much-needed. The work presented in this thesis was focused on the early stages of drug discovery by applying different hit identification and hit expansion strategies in the exploration of two new potential drug targets, glutamine synthetase (GS) and 1-deoxy-D-xylulose-5-phosphate reductoisomerase (DXR). A literature survey was first carried out to identify new Mtb GS inhibitors from compounds known to inhibit GS in other species. Three compounds, structurally unrelated to the typical amino acid derivatives of previously known GS inhibitors, were then discovered by virtual screening and found to be Mtb GS inhibitors, exhibiting activities in the millimolar range. Imidazo[1,2-a]pyridine analogues were also investigated as Mtb GS inhibitors. The chemical functionality, size requirements and position of the substituents in the imidazo[1,2-a]pyridine hit were investigated, and a chemical library was designed based on a focused hierarchical design of experiments approach. The X-ray structure of one of the inhibitors in complex with Mtb GS provided additional insight into the structure–activity relationships of this class of compounds. Finally, new α-arylated fosmidomycin analogues were synthesized as inhibitors of Mtb DXR, exhibiting IC50 values down to 0.8 µM. This work shows that a wide variety of aryl groups are tolerated by the enzyme. Cinnamaldehydes are important synthetic intermediates in the synthesis of fosmidomycin analogues. These were prepared by an oxidative Heck reaction from acrolein and various arylboronic acids. Electron-rich, electron-poor, heterocyclic and sterically hindered boronic acids could be employed, furnishing cinnamaldehydes in 43–92% yield.

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Boukraa, Sadok. "Préparation, réactivité et étude des propriétés fongistatiques et immunostimulantes d'amino-2 thiazoles et d'imidazo-(2,1-B) thiazoles." Besançon, 1987. http://www.theses.fr/1987BESA2030.

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Le travail se divise en deux grandes parties : la premiere concerne la preparation d'aryl-6 imidazo(2,1-b) thiazoles substitues en 3 par des chaines de type acetate d'ethyle, aroylmethyle. (beta -hydroxy beta -aryl)ethyle te arylethyle. Pour ce faire, il a ete necessaire de preparer les amino-2 thiazoles corespondants substitues par ces memes chaines en 4 afin de las opposer a des acetophenones omega -bromees. L'influence des substituants presents est discutee en vue d'aprehender l'evolution des reactions. La seconde partie concerne des essais en tant que fongistatiques et/ou immunostimulants des composes preparees. Il ressort que les aminothiazoles sont plus interessants que les imidazothiazoles auusi bien sur l'inhibition de croissance de mycelium (epidermophyton) ou de germination des spores (candida, aspergillus) que sur la stimulation du lymphocyte t humain

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Cui, Xiuhua. "Asymmetric hydrogenations of aryl alkenes using imidazol-2-ylidene iridium complexes." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2456.

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A library of iridium complexes featuring oxazoline and imidazol-2-ylidene ligands were synthesized by reaction of a library of imidazoles with a second library of oxazoline iodides. These complexes were active catalysts for hydrogenations of aryl substituted monoenes. Tri- and 1,1-disubstituted alkenes were hydrogenated quantitatively with ee??s up to 99% at 1 atm hydrogen pressure. Catalyst, substrate, temperature and pressure effects were studied. The iridium complexes were also used for the kinetic study of hydrogenation of 2,3- diphenylbutadiene. This hydrogenation is a stepwise reaction: one double bond was hydrogenated first, then the second one. Both step hydrogenations were zero order in alkene. The consumption of 2,3-diphenylbutadiene was first order in catalyst, and probably first order in hydrogen pressure too. The enantioselectivity for the first step hydrogenation was low. There were match and mismatch catalyst-substrate relationships for the second step hydrogenation, and the enantioselectivities for this step were catalyst controlled. NMR studies indicated that the initiation of the reaction involved both hydrogen and alkene substrate. A competitive experiment was designed to explore the formation of meso-alkane at first step hydrogenation, and the results indicated that the alkane was formed predominantly via an associative mechanism. Four types of conjugate dienes were synthesized and hydrogenated. Different reactivities and selectivities were obtained for each type of dienes. In the best case, a diene was hydrogenated quantitatively with an excellent ent/meso ratio of 20:1.0 and 99% enantioselectivity. The scope, limitation and potential applications of the reactions were discussed. A selection of the dienes was hydrogenated with the Crabtree??s catalyst, for comparison, and the yields, conversions and diastereoselectivities were inferior to those from iridium-oxazoline-imidazol-2-ylidene catalysts.

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17

Kerscher-Hack, Silke [Verfasser]. "Synthese potentieller GABA-uptake-Inhibitoren mit 1H-Imidazol-4-ylessigsäure- und 3-(1H-Imidazol-2-yl)propansäure-Grundstruktur / Silke Gabriele Hack." München : Verlag Dr. Hut, 2011. http://d-nb.info/1014848482/34.

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Walker, Isabel. "Synthese und Koordination sigma-donor-funktionalisierter Imidazol-2-ylidene und alpha-Diketodiimine." [S.l. : s.n.], 2002. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10236404.

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Turnbull, Stanhope. "Study of Bis-Imidazol-2-Ylidines as Ligands for Transition Metal Catalyzed Coupling Reactions." ScholarWorks@UNO, 2004. http://scholarworks.uno.edu/td/214.

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Two bis-imidazol-2-ylidine N-heterocyclic carbenes have been employed as ancillary ligands in an attempt to illustrate their utility in the palladium-mediated preparation of aryl ethers from aryl halides. Ullman-type homo-coupling of the aryl halides persistently occurred instead of ether formation. One of the well known N-heterocyclic carbenes, IPr, was employed with the same results. A variety of reaction conditions and reagents were investigated including solvents, N-heterocyclic carbene species, palladium source, alkoxide base, palladium to ligand ratio and reaction time. Reactivity of the individual N-heterocyclic carbenes as ancillary ligands in the palladium-catalyzed amination reaction of aryl halides was investigated to determine functionality of the carbenes. Alternative procedures to prepare the key intermediates in the synthesis of the bisimidazol- 2-ylidines were developed. In this study the aryl imidazoles were prepared from the corresponding phenol and carbonyldiimidazole. Subsequent N-alkylation then furnished the Nheterocyclic carbenes in high yield. Novel unsymmetrical N-heterocyclic carbenes with aryl and benzylic side groups have been synthesized as models for the subsequent synthesis of unsymmetrical polymer-bound Nheterocyclic carbenes. The unsymmetrical ligands were employed in the palladium-catalyzed amination of aryl halides and in the Suzuki-Miyaura Reaction. Two Merrifield resin polymerbound N-heterocyclic carbene ligands were then synthesized and employed in the aryl amination and Suzuki-Miyaura Reactions. Both reactions were greatly accelerated by the implementation of microwave heating. The Merrifield resin polymer-bound palladium-ligand complexes have been recycled through several reactions without loss of activity.

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Villarinho, Jardel Gomes. "POTENCIAL ANTIDEPRESSIVO E ANALGÉSICO DO 2-(3,4-DIMETOXI-FENIL)-4,5-DIIDRO-1H-IMIDAZOL (2-DMPI) EM CAMUNDONGOS." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/3835.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Depression and chronic pain coexist in several patients and may be modulated by the same neurotransmitter systems. In this context, various studies have demonstrated that antidepressants from the class of the inhibitors of monoamine oxidase-A (MAO-A) enzyme presented antinociceptive effect in different pain models in experimental animals, as well as analgesic action in clinic studies. Thus, in the present study were evaluated the MAO-A inhibitory properties, as well as the antidepressant and antinociceptive potential of the novel imidazoline compound 2-(3,4-dimethoxy-phenyl)-4,5-dihydro-1H-imidazole (2-DMPI) in mice. 2-DMPI showed to be a mixed, reversible and preferential MAO-A inhibitor. The treatment with 2-DMPI (100-1000 μmol/kg, s.c.) produced an antidepressant-like effect in the tail suspension test without affecting motor activity of the animals. The mice treated with 2-DMPI showed a decrease in serotonin and dopamine turnover in specific brain regions, suggesting that the antidepressant-like effect of this compound was mediated by serotonergic and dopaminergic systems. This was confirmed by experiments showing that the antidepressant-like effect of 2-DMPI was abolished by pretreatment with serotonergic and dopaminergic receptor antagonists. In order to evaluate a possible antinociceptive action of 2-DMPI, a mice model of neuropathic pain, induced by chronic constriction injury (CCI) of the sciatic nerve was used. It was observed that mice submitted to CCI presented an increase in MAO-A activity in lumbar spinal cord compared with sham-submitted mice and that the treatment with 2-DMPI (30-300 μmol/kg, s.c.) reversed the CCI-induced mechanical hyperalgesia. Furthermore, the antihyperalgesic effect of 2-DMPI was reversed by intrathecal injection of the serotonergic 5-HT3 receptor antagonist ondansetron (10 μg/site). These results suggest that 2-DMPI, due to its ability to modulate MAO-A activity and, consequently, the monoaminergic systems, could be a promising prototype to the development of new drugs with antidepressant and analgesic properties.
A depressão e a dor coexistem em muitos pacientes e podem ser moduladas pelos mesmos sistemas de neurotransmissores. Nesse contexto, diversos estudos têm demonstrado que antidepressivos da classe dos inibidores da enzima monoamina oxidase-A (MAO-A) apresentam efeito antinociceptivo em diferentes modelos de dor em animais experimentais, assim como ação analgésica em estudos clínicos. Em vista disso, no presente estudo foram avaliadas as propriedades inibitórias sobre a atividade da MAO-A, assim como os potenciais antidepressivo e antinociceptivo do novo composto imidazolínico 2-(3,4-dimetoxi-fenil)-4,5-diidro-1H-imidazol (2-DMPI) em camundongos. Foi observado que o 2-DMPI é um inibidor misto, reversível e preferencial da MAO-A. O tratamento com 2-DMPI (100-1000 μmol/kg, s.c.) produziu um efeito tipo-antidepressivo no teste de suspensão da cauda, sem afetar a atividade motora dos animais. Os camundongos tratados com 2-DMPI (300 μmol/kg, s.c.) apresentaram uma diminuição na taxa de renovação da serotonina e da dopamina em regiões cerebrais específicas, sugerindo que o efeito tipo-antidepressivo desse composto foi mediado pelos sistemas serotoninérgico e dopaminérgico. Isto foi confirmado por experimentos que mostraram que o efeito tipo-antidepressivo do 2-DMPI foi abolido pelo pré-tratamento com antagonistas de receptores serotoninérgicos e dopaminérgicos. A fim de avaliar um possível efeito antinociceptivo do 2-DMPI, foi utilizado um modelo de dor neuropática, induzida pela injúria por constrição crônica (CCI) do nervo ciático, em camundongos. Observou-se que os camundongos submetidos à CCI apresentaram um aumento na atividade da MAO-A na medula espinhal lombar comparado com os animais falso-operados e que o tratamento com 2-DMPI (30-300 μmol/kg, s.c.) reverteu a hiperalgesia mecânica induzida pela CCI. Além disso, o efeito antinociceptivo do 2-DMPI foi revertido pela administração intratecal do antagonista do receptor serotoninérgico 5-HT3, ondansetrona (10 μg/sítio). Esses resultados sugerem que o 2-DMPI, devido à sua capacidade de modular a atividade da MAO-A e, consequentemente, os sistemas monoaminérgicos, parece ser um protótipo promissor para o desenvolvimento de novos fármacos com propriedades antidepressiva e analgésica.

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Chatwin, Sarah Louise. "Ruthenium hydride complexes bearing the ligand 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene." Thesis, University of Bath, 2007. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443541.

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Gonsales, Stella de Almeida 1987. "Dipirrometenos, 2-ariloilpirróis e derivados de bis-imidazol : síntese, caracterização e seus compostos de coordenação." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248586.

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Orientadores: André Luiz Barboza Formiga, Pedro Paulo Corbi
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
Made available in DSpace on 2018-08-20T20:33:33Z (GMT). No. of bitstreams: 1 Gonsales_StelladeAlmeida_M.pdf: 5138050 bytes, checksum: 48050f171b28aaaec7dc54a01a7ee17f (MD5) Previous issue date: 2012
Resumo: erivados de pirrol e imidazol, juntamente com seus complexos de Cu(II) e Zn(II). Após diversas tentativas de síntese do 5-fenildipirrometeno pela rota tradicional, obteve-se o produto desejado porém em baixíssimos rendimentos. Os 2-ariloilpirróis foram sintetizados com sucesso partindo-se de cloreto de ácido e pirrol, obtendo-se assim o 2-benzoil-3,5-dimetilpirrol (2-bz-pirrol) e o 2-isonicotinoil-3,5-dimetilpirrol (2-pypirrol) como produtos. Os compostos foram caracterizados por DRX de monocristal, MS, IV, UV-Vis e H e C RMN. Realizaram-se ensaios biol'ogicos com os ligantes obtidos, assim como com os complexos de Cu(II) destes ligantes. Outro ligante, tridentado, o 2,6-bis(imdazol-2-il)piridina (impy) foi sintetizado com sucesso e utilizado na síntese de um complexo inédito de cobre. Sua estrutura também foi determinada por difracão de raios X de monocristal, dentre outras técnicas, revelando uma estrutura binuclear não usual formada por uma ponte de cloreto
Abstract: In this work we present the synthesis of three new ligands derived from pyrrole and imidazole subunits, along with their Cu(II) and Zn(II) complexes. After many attempts to achieve the synthesis of 5-phenyldipyrromethene using the classical method, we obtained the desired product but in very low yields. Two 2- ariloylpyrroles have been synthesized from the acid chloride and pyrrole, achieving both 2-benzoyl-3,5-dimethylpyrrole (2-bz-pirrol) and 2-isonicotinoyl-3,5-dimethylpyrrole (2-py-pirrol) as products. These compunds were charactherized by single crystal XRD, MS, FTIR, UV-Vis and H e C NMR. Biological assays were performed with the obtained ligands and their Cu(II) complexes. Another ligand, tridentate, 2,6-bis(imdazole-2-yl)pyridine (impy) was successfully synthesized and used in the achievement of a novel Cu(II) complex. Its structure was also determined by single crystal XRD, among with other techniques, revealing an unusual chloride bridged binuclear structure
Mestrado
Quimica Inorganica
Mestre em Química

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McGuire, Kelly Lewis. "Governing Dynamics of Divalent Copper Binding by Influenza A Matrix Protein 2 His37 Imidazole." BYU ScholarsArchive, 2020. https://scholarsarchive.byu.edu/etd/8647.

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Influenza A is involved in hundreds of thousands of deaths globally every year resulting from viral infection-related complications. Previous efforts to subdue the virus by preventing proper function of wild-type (WT) neuraminidase (N), and M2 proteins using oseltamivir and amantadine (AMT) or rimantadine (RMT), respectively, exhibited success initially. Over time, these drugs began exhibiting mixed success as the virus developed drug resistance. M2 is a proton channel responsible for the acidification of the viral interior which facilitates release of the viral RNA into the host. M2 has a His37-tetrad that is the selective filter for protons. This protein has been demonstrated to be a feasible target for organic compounds. However, due to a mutation from serine to asparagine at residue 31 of M2, which is found in the majority of influenza strains circulating in humans, AMT and RMT block is insufficient. From simulations, it is unclear whether the insensitivity results from weak binding or incomplete block. The question of how the S31N mutation caused MT and RMT insensitivity in M2 is addressed here by analyzing the binding kinetics of AMT and RMT using the two-electrode voltage clamp electrophysiology method. The dissociation rate constant (k2) is dramatically increased compared to WT for both AMT and RMT, by 1500-fold and 17000-fold respectively. Testing of AMT at 10 mM demonstrates complete block, albeit weak, of the S31N M2 channel. At 10 mM, RMT does not reach complete block even though the binding site is saturated. When RMT is in the bound state, it is not blocking all the current, and is binding without block. These results motivated the development of novel M2 blockers using copper complexes focusing on the His37 complex in M2. I hypothesized that copper complexes would bind with the imidazole of a histidine in the His37 complex and prevent proton conductance. The His37 complex is highly conserved in the M2 channel and, therefore, would be important target for influenza therapeutics. By derivatizing the amines of known M2 blockers, AMT and cyclooctyalmine, to form the iminodiacetate or iminodiacetamide, we have synthesized Cu(II) containing complexes and characterized them by NMR, IR, MS, UVâ€“vis, and inductively coupled plasma mass spectroscopy (ICP-MS). The copper complexes, but not the copper-free ligands, demonstrated H37-specific blocking of M2 channel currents and low micromolar anti-viral efficacies in both Amt-sensitive and Amt-resistant IAV strains with, for the best case, nearly 10-fold less cytotoxicity than CuCl2. Isothermal titration calorimetry was used to obtain enthalpies that showed the copper complexes bind to one imidazole and curve fitting to the electrophysiology data provided rate constants for binding in the M2 channel. Computational chemistry was used to obtain binding geometries and energies of the copper complexes to the His37-tetrad. The results show that the copper complexes do bind with the His37 complex and prevent proton conductance and influenza infection.

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24

Jagenbrein, Martin. "Complexes of Bi, Pd, Ir and Hg and N-heterocyclic ligands." Thesis, Strasbourg, 2014. http://www.theses.fr/2014STRAF023.

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L’objectif de cette thèse était la synthèse de nouveaux pro-ligands NHC et de leurs complexes métalliques correspondants, en particulier de l’iridium. La tentative de trouver de nouvelles voies de synthèse de complexes NHC à partir des imidazole-2-thiones correspondants n’a pas donné les résultats attendus.Cependant, il a été possible de préparer des composés de coordination intéressants de ces imidazole-2-thiones : ainsi, un complexe de Bi a été préparé et a pu servir d’agent de transmétallation vers le Pd. De nouveaux proligands NHC de type « pince » et plusieurs de leurs complexes d’iridium ont été préparés. Plusieurs complexes de mercure portant ces ligands ont été synthétisés. De plus, une série de sels d’imidazolium portant des fonctionnalités potentiellement hémilables a été préparée et leur réactivité vis-à-vis de l’iridium étudiée
The purpose of this thesis was the synthesis of novel pro-ligands to NHCs and their corresponding metal complexes, notably of iridium. While the attempt to find a new pathway to obtain NHC complexes starting from the corresponding imidazole-2-thiones did not yield the expected result, it was possible to obtain interesting coordination compounds from those imidazole-2-thiones themselves:A dinuclear Bi complex was prepared that served as an effective transmetallation agent toward Pd. Novel pincer-type NHC pro-ligands were obtained, and several iridium complexes of their corresponding NHC ligands were prepared. Furthermore, several mercury complexes of these ligands were synthesized. Finally, a series of imidazolium salts bearing potentially hemilabile functionalities were prepared and their reactivity toward Ir was studied

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Zhang, Yin. "Backbone decoration of imidazol-2-ylidene ligands with amino groups and their application in palladium catalyzed arylative amination reaction." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30109/document.

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Ce travail s'inscrit dans le cadre de la chimie des carbènes N-hétérocycliques (NHC) et s'articule autour de la fonctionnalisation directe de l'hétérocycle des l'imidazol-2-ylidènes par substitution formelle d'un ou deux groupements diméthylamino. Deux nouvelles catégories de NHCs ont d'abord été obtenues par cette stratégie, dénommées 4-(diméthylamino)imidazol-2-ylidène IArNMe2 et 4,5-bis(diméthylamino)imidazol-2-ylidène IAr(NMe2)2. Les sels d'imidazolium précurseurs de ces NHCs, à savoir le triflate de 4-(diméthylamino)imidazolium (IArNMe2)·HOTf et le triflate de 4,5-bis(diméthylamino)imidazolium (IAr(NMe2)2)·HOTf, ont été synthétisés en couplant la formamidine disubstituée correspondante avec le N,N-diméthyl-chloroacétamide et le 1,2-dichloro-1,2-bis(diméthylamino)éthylène généré in situ respectivement. La quantification des propriétés électroniques des deux nouveaux NHCs a été réalisée à l'aide des complexes de type [Rh(IMes(NMe2)xCl(CO)2], montrant que la donation électronique des ligands NHCs augmente séquentiellement par la décoration avec un ou deux groupements diméthylamino, tandis que les propriétés de p-rétrodonation des NHCs ne sont que légèrement influencées. Par la suite, les complexes de palladium Pd-PEPPSI-IPrNMe2 et Pd-PEPPSI-IPr(NMe2)2 (PEPPSI : Pyridine Enhanced Preparation Purification Stabilization and Initiation) ont été préparés par des voies de complexation classiques. Les propriétés stériques des ligands a été évaluée par la mesure du pourcentage de volume occupé (%Vbur), et il est apparu que les propriétés stériques de ces deux nouveaux ligands NHCs sont également accrues. Les activités catalytiques des deux pré-catalyseurs ont été évaluées en amination de type Buchwald-Hartwig et comparées avec celle de la référence Pd-PEPPSI-IPr. Le pré-catalyseur Pd-PEPPSI-IPr(NMe2)2 s'est révélé le plus actif en amination des chlorures d'aryle à température ambiante. Il constitue également le catalyseur Pd-NHC le plus efficace et le plus général connu à ce jour en permettant de réaliser l'amination des chlorures d'aryle avec une charge de catalyseur très faible (jusqu'à 50 ppm), ou à l'aide d'une base faible telle que le carbonate de césium, et même d'activer les tosylates d'aryle, substrats beaucoup plus difficiles que les chlorures d'aryle . Afin de rationaliser au mieux les effets observés en catalyse en termes de propriétés stéréoélectroniques des ligands NHCs, le squelette arrière aminé des imidazol-2-ylidènes a été dérivatisé plus avant, soit en augmentant la contrainte stérique du groupe NMe2 dans IAr(NMe2) en ciblant le ligand IAr(NiPr2), soit en remplaçant formellement un des groupes amino par un groupe éléctro-attracteur tel un halogène dans le ligand IAr(NMe2)2. Alors que le sel d'imidazolium (IArNiPr2)·HOTf a été synthétisé suivant la même méthode que (IArNMe2)·HOTf, l'halogénation oxydante du squelette d'arrière de (IArNMe2)·HOTf par du NCS ou du NBS a donné les sels (IArNMe2, X)·HOTf avec de très bons rendements dans des conditions très douces. Il convient de noter que cette réactivité originale a été également observée sur les complexes de rhodium(I) et le palladium(II) du ligand IAr(NMe2). Les influences électroniques et catalytiques de ces modifications ont été étudiées de la même façon
This work is incorporated within the framework of the chemistry of N-Heterocyclic Carbenes (NHCs) and aims at functionalizing the skeleton of imidazol-2-ylidenes by attachment of one or two amino groups. Two new NHC classes were first obtained by this strategy, namely the 4-(dimethylamino)imidazol-2-ylidene IArNMe2 and the 4,5-bis(dimethylamino)imidazol-2-ylidene IAr(NMe2)2. The synthesis of the precursors of these NHCs, the 4-(dimethylamino)imidazolium triflates (IArNMe2)·HOTf and the 4,5-bis(dimethylamino)imidazolium triflates (IAr(NMe2)2)·HOTf is based on the coupling between the corresponding disubstituted formamidine and either an a-chloroacetamide for the mono-amino derivative or a reactive dichlorodiaminoethene for the bis-amino analogue. The electronic properties of the resulting new NHCs ligands have been studied by measurement of their Tolman Electronic Parameter (TEP) values obtained from the IR spectra of the complexes [Rh(IMesXY)Cl(CO)2] and by 77Se NMR spectroscopy of their corresponding selenoureas [(IMesXY)=Se]. It was shown that the electronic donation of the carbenic carbon sequentially increases by decoration with one or two amino groups respectively whereas the p-accepting properties of the NHC are only slightly or even not affected by the adjunction of the NMe2 groups on the imidazolyl backbone. Later, the synthesis of the two new PEPPSI-type palladium pre-catalysts PEPPSI-Pd-IPrNMe2 and Pd-PEPPSI-IPr(NMe2)2 were successfully achieved. From the calculated the percent buried volume %Vbur which is related to the steric properties of the two supporting NHC ligands, it appeared that grafting one amino group onto the backbone already leads to significant improvement of steric congestion while the second amino only results in a slight increase of the steric issue. The catalytic efficiencies of both pre-catalysts were evaluated in the benchmark Buchwald-Hartwig amination and compared with this of the reference PEPPSI-Pd-IPr. The bis-aminated pre-catalyst Pd-PEPPSI-IPr(NMe2)2 was shown to be the most active and stable pre-catalyst, and it was shown to be also highly efficient in more challenging amination reaction. It indeed allows to carry out the amination of aryl chlorides at low catalyst loadings or by using a mild base such as cesium carbonate, and even to activate the aryl tosylates, which are more difficult substrates than aryl chlorides. In order to study the critical stereoelectronic properties of the NHC ligands for the efficiency of the corresponding catalysts, further derivatization of the heterocyclic backbone was carried out, either by increasing the bulkiness of the mono-amino group from dimethylamino to diisopropylamino group to generate the carbene IArNiPr2, or by formally replacing one dimethylamino group by an halogen X in the bis-aminoimidazo-2-ylidene to give the carbenes IArNMe2,X. While the imidazolium salts (IArNiPr2)·HOTf was synthesized following the same method as (IArNMe2)·HOTf, the oxidative halogenation of the backbone of (IArNMe2)·HOTf with a N-halosuccinimide afforded (IArNMe2,X)·HOTf in good yields under very mild conditions. Noteworthy, this original reactivity was also observed on the rhodium and palladium complexes of this ligand

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Silva, José Atalvanio da. "Estudo Cristaloquimico de dois derivados Naftoquinônicos pela aplicação de difração de raios X: 4,5-Diidro-6,6-Dimetil-6h-2-(3 -Metilfenil)-Furan[B-4,3] Nafto[1,2-D] Imidazol (Nppn3171) E 4,5-Diidro-6,6-Dimetil 6h-2 (Fenil)-Piran [B-4,3]-Nafto[1,2-D]-Imidazol (Nppn3073)." Universidade Federal de Alagoas, 2010. http://repositorio.ufal.br/handle/riufal/1101.

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This study aimed to perform the collection of the intensities of diffracted X-ray beam, solving the crystal structures, refine the collected data to compare the molecular structures obtained, the proposals submitted by the group of the Pesquisa em Produtos Naturais (NPPN) da Universidade Federal do Rio de Janeiro (UFRJ) and to characterize the crystal packing identifying possible interactions of hydrogen. In Chapter I, has an introduction to organic compounds as potential pharmaceutical and distribution of Chagas disease in the world and in Brazil, highlighting data from the State of Alagoas. In Chapter II presents a theoretical foundation of X-rays as well as the concept of crystal, followed by Chapter III, using materials and methods and in Chapter IV, are the results and discussions. The compounds studied in this work were 4,5-dihydro-6 ,6-dimethyl-6H-2-(3'-methylphenyl)-furan [B-4,3] naphtha [1,2-D] Imidazole (NPPN3171) and 4,5-dihydro-6 ,6-dimethyl-6H-2 (phenyl)-piran [B-4, 3]-naphtha [1,2-D]-imidazole (NPPN3037). The single crystal samples were courtesy of NPPN/ UFRJ, in the person of Professor Antonio Ventura Pinto. The crystals were selected, glued on glass fibers and set the goniometric head. Data were collected using an automatic diffractometer Kappa CCD. The structures were solved using the software package contained in the WinGX v1.70.01. The compound NPPN3171crystallizes in monoclinic crystal system, space group P21/c with the following parameters a = 9.2587(2)Å, b = 9.8049(4)Å, c = 19.3851 (7) Å; β = 101.365 (2) and Z = 4 molecules /cell. Were collected 3506 unique reflections with use of automatic KappaCCD diffractometer using the Kα radiation of molybdenum ( = 0.71073 Å) monochromatized by a graphite crystal. Were considered 2382 observed reflections giving a final discrepancy index (Robs) of 0.0555. In the crystal packing observed the presence of classical intermolecular hydrogen bonds. To compound NPP3073 the linear parameters were obtained: a = 9.0547(2)Å, b = 10.5956(5)Å, c = 18.7071(10) Å; β = 102.467º (3); crystal system monoclinic space group P21/c and Z = 4 molecules/unit cell. The 2381 observed reflections gave a Robs = 0.1502 reflecting the low quality of data as seen in Rint = 0.1179. Analyzing the molecular structure is observed the presence of a secondary intramolecular interaction (C - H... O)
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Este trabalho teve como objetivos realizar a coleta das intensidades dos feixes de raios X difratados, resolver as estruturas cristalinas, refinar os dados coletados, comparar as estruturas moleculares obtidas, com as propostas fornecidas pelo grupo do Núcleo de Pesquisas de Produtos Naturais (NPPN), da Universidade Federal do Rio de Janeiro (UFRJ) e caracterizar o empacotamento cristalino identificando as possíveis interações de hidrogênio. No capítulo I, tem-se uma introdução sobre os compostos orgânicos como candidatos á fármacos e a distribuição da doença de Chagas no mundo e no Brasil, destacando dados do Estado de Alagoas. No capítulo II, apresenta-se uma fundamentação teórica sobre raios X bem como o conceito de cristal, seguido do capítulo III, com materiais e métodos e no capítulo IV, têm-se os resultados e as discussões dos mesmos. Os compostos estudados neste trabalho foram: 4,5-diidro-6,6-dimetil-6H-2-(3 -metilfenil)-furan[B-4,3] nafto[1,2-D] imidazol (NPPN3171) e 4,5-diidro-6,6-dimetil-6H-2 (fenil)-piran [B-4,3]-nafto[1,2-D]-imidazol (NPPN3037). As amostras monocristalinas foram gentilmente cedidas pelo NPPN da UFRJ, na pessoa do professor Antonio Ventura Pinto. Os cristais foram selecionados, colados em fibra de vidro e fixados na cabeça goniométrica. Os dados foram coletados usando-se um difratômetro automático Kappa CCD. As estruturas foram resolvidas utilizando-se o pacote de programas contido no WinGX v1.70.01. O composto NPPN3171 cristaliza no sistema cristalino monoclínico, grupo espacial P21/c com os seguintes parâmetros a = 9,2587(2)Å, b = 9,8049(4)Å, c = 19,3851(7)Å; β = 101,365o(2) e Z = 4 moléculas/cela. Foram coletadas 3506 reflexões únicas com uso do Difratômetro automático KappaCCD e utilizando a radiação Kα do molibidênio (0,71073Å) monocromatizada por um cristal de grafite. Foram consideradas 2382 reflexões observadas fornecendo um índice de discordância final, (Robs) de 0,0555. No empacotamento cristalino verificou-se a presença de ligações de hidrogênio intermoleculares clássicas. Para o composto NPP3073 os parâmetros lineares obtidos foram: a = 9,0547(2)Å, b = 10,5956(5)Å, c = 18,7071(10)Å; β = 102,467o(3); sistema cristalino monoclínico com grupo espacial P21/c e Z = 4 moléculas/cela unitária. As 2381 reflexões observadas forneceram um Robs = 0,1502 refletindo a baixa qualidade dos dados como verificado no Rint = 0,1179. Analisando a estrutura molecular observa-se a presença de uma interação intramolecular secundária (C H...O)

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27

César, Vincent. "Ligands carbènes n-hétérocycliques chiraux par assemblage modulaire d'unités oxazolines et imidazol-2-ylidènes : Synthèse et application en catalyse homogène." Université Louis Pasteur (Strasbourg) (1971-2008), 2004. https://publication-theses.unistra.fr/public/theses_doctorat/2004/CESAR_Vincent_2004.pdf.

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Les carbènes N-hétérocycliques représentent une alternative intéressante aux ligands phosphinés en catalyse homogène. Le développement d'une version chirale de ces ligands carbènes constitue le but principal de ce travail de thèse. Tout d'abord, une large gamme de sels d'oxazolinyl/imidazolium, précurseurs des ligands bidentates cibles, a été synthétisée à l'aide d'une approche modulaire. Nous avons ensuite réalisé la complexation du représentant achiral de cette famille de ligands sur divers centres métalliques tels que du palladium(II) ou du rhodium(I). Le complexe de palladium(II) permet le couplage des chlorures d'aryles activés pour les réactions catalytiques de Heck et Suzuki. Les études réalisées sur les complexes neutres pentacoordinés de rhodium(I) ont mis en lumière deux processus fluxionnels que sont la pseudo-rotation de Berry et un échange intermoléculaire de ligand bromure. Nous avons également étudié la réaction d'hydrosilylation asymétrique des cétones à l'aide des complexes chiraux de rhodium(I). Le système catalytique a été optimisé grâce notamment à la modularité des ligands. Il présente une activité catalytique remarquable et montre un excellent caractère énantiosélectif pour les cétones prochirales à substituants aryle-alkyle et surtout dialkyle avec des excès énantiomériques atteignant 95%. Enfin, la dernière partie décrit la synthèse d'un ligand carbène/bisoxazoline tridentate chiral qui pourrait posséder un fort pouvoir d'induction asymétrique. Un complexe de rhodium(III) a été préparé. Sa structure moléculaire obtenue par diffraction des rayons X confirme la coordination tridentate et méridionale du ligand
This work, part of the field of homogeneous catalysis, describes the development of chiral N heterocyclic carbenes based on a modular assembly between oxazoline and imidazolylidene units. First a large library of imidazolium salts, precursors for the bidentate ligands oxazolinyl-imidazolylidene, was obtained by a single coupling step. The second part is devoted to the coordination chemistry of the achiral representative of this family of ligands. Several transition metal complexes were synthesized and analyzed by X-ray diffraction studies. The palladium(II) complex was found to catalyze the coupling of activated aryl chlorides in catalytic Heck and Suzuki reactions. Cationic, chiral rhodium(I) complexes were then applied as catalysts in the asymmetric catalytic hydrosilylation reaction of prochiral ketones. The optimized catalytic system is remarkably active and induces high enantioselectivity for aryl-alkyl ketones and, in particular, for dialkyl ketones (enantiomeric excess up to 95%). In the last part the synthesis and complexation on a rhodium(III) centre of a chiral, tridentate bisoxazoline-carbene ligand are reported. This carbene is effectively tridentate with a quasi planar skeleton and could be highly efficient as a stereoinducting ligand for asymmetric catalysis

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28

Ba, Lalla Aîcha Kirsch Gilbert. "Nouvelles approches vers la synthèse de l'acide 5-(2-oxo-2,3-dihydro-1H-thiéno[3,4-d]imidazol-4-yl) pentanoïque (tétradéhydrobiotine)." [S.l.] : [s.n.], 2007. ftp://ftp.scd.univ-metz.fr/pub/Theses/2007/Ba_Lalla.Aicha.SMZ0745.pdf.

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Cândido, Manuela Chaves Loureiro. "Estudo da Reatividade dos íons complexos cis-[Ru(bpy)2(L)(NO)]n+ onde L=imidazol, 1-metilimidazol, tioureia e sulfito." reponame:Repositório Institucional da UFC, 2011. http://www.repositorio.ufc.br/handle/riufc/14978.

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CÂNDIDO, M. C. L Estudo da Reatividade dos íons complexos cis-[Ru(bpy)2(L)(NO)]n+ onde L=imidazol, 1-metilimidazol, tioureia e sulfito. 2011. 152 f. Dissertação (Mestrado em Química) - Centro de Ciências, Universidade Federal do Ceará, Fortaleza, 2011.
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We carried out studies of chemical reactivity, electrochemistry and photochemistry of complexes cis-[Ru(bpy)2(L)(NO)](PF6)n, where L = imidazole, 1-methylimidazole, thiourea and sulfite. Were chosen, therefore, two ligands being  donors and two with ligands that act as -recipient and the results indicated that the nature and strength of these ligands directly influence the strength of the back donation between the metal center and coordinated nitric oxide. The infrared spectra showed a characteristic frequency of nitric oxide coordinated as NO+, and there was variation in the observed value of frequency of NO stretching, dependant of the auxiliary ligand. The results indicate that the backbonding between Ru and NO+ is stronger in the complex featuring the sulfite ligand in the coordination sphere, that complex having a minimum value to that specific stretching frequency, when compared to the other complexes. The experimental data corroborate with the Lever parameter values for the ligands, indicating the contribution of them to the electron density of the metal. The cyclic voltammetry performed in aqueous media indicate that the reduction of NO+ species to NO0 is facilitated with the increase of electron density donation from auxiliary ligands to the metallic center. And the differential pulse voltammetry indicates the possibility of the formation of aqueous-complex from a chemical reaction, after coordinated NO+ reduction. This work have shown that the photochemical release of nitric oxide from the light stimulation of complex solutions is consistent, even being possible to determine the species formed as a product of the photolysis and subsequent calculations of quantum yield of NO0 realese. Quantification of nitric oxide release was performed indirectly, using the technique of square wave voltammetry, which was efficient for the purpose. It was also used a selective electrode for free NO0 molecule, confirming that irradiation of NO+ compounds solutions actually cause the release of coordinated nitric oxide (NO+) to its active form in biological environment.
Neste trabalho foram realizados estudos de reatividade química, eletroquímica e fotoquímica dos complexos cis-[Ru(bpy)2(L)(NO)](PF6)n, onde L= imidazol, 1-metilimidazol, tiouréia e sulfito. Foram escolhidos, portanto, dois ligantes auxiliares com características  doadoras e dois com características  receptoras e os resultados obtidos indicaram que a natureza e força destes ligantes influenciam diretamente na retrodoação existente entre o centro metálico e o óxido nítrico coordenado. Os espectros de infravermelho apresentaram freqüência característica de óxido nítrico coordenado na forma NO+, sendo que houve variação dos valores conforme a variação do ligante auxiliar. Os resultados indicam que a interação existente (retrodoação) entre o Ru e o NO é mais forte para o complexo que apresenta o ligante sulfito na esfera de coordenação, por apresentar um menor valor de freqüência de estiramento quando comparado aos demais complexos. Os dados experimentais corroboram com os valores do parâmetro de Lever encontrados para os ligantes, que indicam a contribuição dos mesmos para a densidade eletrônica do metal. Os ciclovoltamogramas, realizados em meio aquoso, indicam que a redução da espécie NO+ a NO0 é facilitada quanto maior for a doação de densidade eletrônica do ligante “L” para o centro metálico. E a voltametria de pulso diferencial indica a possibilidade da formação do aquo-complexo a partir de uma reação química após a redução de óxido nítrico. Os estudos fotoquímicos mostraram que a liberação de óxido nítrico a partir do estímulo luminoso de soluções dos complexos é consistente, sendo possível inclusive a determinação da espécie formada como produto da fotólise e posteriores cálculos de rendimento quântico da formação das mesmas. A quantificação da liberação de óxido nítrico foi realizada de maneira indireta, utilizando a técnica de voltametria de onda quadrada, que se mostrou eficiente para o objetivo. E foi utilizado também um eletrodo seletivo para a molécula de NO0 livre, confirmando que a irradiação das soluções realmente leva a liberação do óxido nítrico coordenado na sua forma ativa em meio biológico.

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Koner, Abhishek [Verfasser]. "On the imidazole-2-thione-based route to tricyclic 1,4-diphosphinines: synthesis, structures and reactions / Abhishek Koner." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/1154485862/34.

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Dlamini, Samkeliso Mpendulo Dlamini. "Synthesis and Biological Evaluation of HDAC Inhibitors with 1-(1H-imidazol-2-yl)ethan-1-one Moiety as the Metal-Binding Group." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1501770195684609.

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32

Ba, Lalla Aïcha. "Nouvelle approche vers la synthèse de l'acide 5-(-2-oxo-2,3-dihydro-1H-thiéno[3,4-d]imidazol-4-yl) pentanoïque (la tétradéhydrobiotine)." Thesis, Metz, 2007. http://www.theses.fr/2007METZ045S/document.

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La biotine ou vitamine H est un coenzyme impliqué dans les processus de transfert de dioxyde de carbone sur diverses molécules naturelles. Sa très grande affinité avec l'avidine ou la streptavidine est couramment exploitée dans le cadre de différentes méthodes d'analyse biochimiques telles que la purification et la détection de protéines. Cependant cette affinité très élevée peut aussi constituer un inconvénient suivant l'utilisation recherchée car la rupture de l'interaction avidine-biotine-protéine d'intérêt implique des conditions de dénaturation drastiques peu compatibles avec l'obtention d’une protéine encore active. La préparation de nouveaux analogues de la biotine présentant une affinité modérée vis-à-vis de l’avidine et de la streptavidine pourrait permettre de faciliter la purification de protéine dans leur état natif. Dans cette optique et en collaboration avec l'équipe de biologistes de notre laboratoire, notre projet est de synthétiser un analogue de la biotine : la 2,3,4,5-tétradéhydrobiotine, puis d'évaluer l'interaction de ce composé avec l’avidine. Dans nos travaux nous avons isolé différents intermédiaires intéressants qui pourront être utilisés dans la synthèse de la tétradéhydrobiotine. Lors de cette étude nous avons également synthétisé de nouveaux thiéno[2,3-d]imidazolones substitués en position 5 au départ de l'hydantoïne
Intracellular biotin is a coenzyme in carbon dioxyde transport. Futhermore because of their high affinity, avidin-biotin or streptavidin-biotin coupling is often used in different biochemical analyses such as protein purification and detection. The high avidin/streptavidin-biotin affinity can also constitute a drawback since proteins require to be denaturated in order to be released, and therefore are often lacking activity. In order to identify pure and active proteins target using this methodology, our aim was to synthesize an analog of biotin: 2,3,4,5-tetradehydrobiotin. We have isolated different key intermediates for the synthesis of tetradehydrobiotin. During this study we also synthesize news thieno[2,3-d]imidazolones starting from hydantoin

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Costa, Miriam. "Estudo do processo e dos produtos da polimerização de biodiesel de óleo de soja com anidrido ftálico e 2-metil-imidazol utilizando biodiesel como solvente." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2011. http://hdl.handle.net/10183/36116.

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Este trabalho apresenta o estudo da polimerização de metil-ésteres epoxidados do óleo de soja (MEE), com anidrido ftálico (AF) e 2-metil-imidazol (2MI) utilizando biodiesel (BD) do óleo de soja como solvente, assim como a caracterização dos produtos obtidos. A região de gelificação para o sistema MEE/AF/2MI, na ausência de BD como solvente, foi determinada pela teoria de Flory, estando compreendida entre as frações molares de MEE (XMEE) 0,33 a 0,54. A composição estequiométrica experimental do sistema MEE/AF/2MI na ausência de BD como solvente foi determinada através da avaliação da entalpia de polimerização (H), estando próxima a XMEE=XAF=0,5. H superiores a 76 J/g foram observados para as amostras compreendidas na região de gelificação teórica. Posteriormente, a composição estequiométrica foi mantida fixa e foram produzidos diversos polímeros variando apenas a quantidade BD como solvente. Os parâmetros cinéticos e termodinâmicos da polimerização em meio de solvente foram avaliados via DSC. Os resultados mostram que BD atua como solvente na reação de polimerização e que há um efeito de compensação entre a Energia de Ativação e o logaritmo do fator pré-exponencial. O aspecto físico e a solubilidade dos polímeros produzidos estão de acordo com o previsto pela teoria de Flory. Os testes de inchamento sugerem que o grau de reticulação é propriedade intrínseca do sistema reacional, pouco afetado pela presença do solvente. O comportamento térmico foi investigado utilizando as técnicas de DSC e TGA. O sistema apresenta duas transições térmicas na faixa de -13 a 20°C. As amostras apresentam duas faixas de degradação, sendo a primeira correspondente a inclusão do BD no retículo, o qual foi eliminado via o processamento térmico aqui proposto. O efeito da compensação foi novamente observado no estudo da cinética de degradação térmica. Ensaios de tensão-deformação por compressão-plana demonstram que os polímeros possuem características de materiais dúcteis. A morfologia das amostras foi investigada pela técnica de Microscopia Eletrônica de Varredura e indicam que o aumento da percentagem de BD na amostra aumenta a rugosidade e presença de domínios vazios na matriz polimérica.
This work present the polymerization study of the epoxidized methyl esters (MEE) obtained from soybean oil, with phthalic anhydride (AF) and 2-methyl-imidazole (2MI) using soybean oil biodiesel (BD) as solvent, as well as the products characterization. The gelation region for the system MEE/AF/2MI without BD was determined using the Flory’s theory and it occurs for MEE molar fraction (XMEE) between 0.33 to 0.54. The evaluation of the polymerization enthalpy (H) indicates that the experimental stoichiometric composition of the system MEE/AF/2MI without solvent is near to XMEE=XAF=0.5. H values higher than 76 J/g were observed for samples located in the theoretical gelation region. After, the stoichiometric composition was fixed and different polymers were produced varying only the amount of BD as a solvent. Kinetics and thermodynamics parameters of the polymerization using solvent were evaluated by DSC technique. The results show that BD acts as solvent in the polymerization reaction and a compensation effect between activation energy and pre-exponential factor logarithm was observed. The physical aspects and solubility experiments demonstrated the validity of the predictions by Flory’s theory. The swelling tests suggest that the crosslink degree is an intrinsic property of the system and it is practically unaffected by the solvent. The thermal behavior was investigated using DSC and TGA techniques. The system presents two thermal transitions in the range between -13 to 20°C. The samples demonstrated two degradations; the first is related to the BD in the network, which was eliminated by the thermal treatment. The compensation effect was observed in the thermal degradation kinetics. Stress-strain curves evaluated by plane strain compression show that the polymers behave as ductile materials. The morphology of the samples was investigated by scanning electron microscopy and indicates that the increase in %BD increases the roughness and the presence of voids in the polymeric matrix.

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Deschamps, Jérôme. "Diacétylènes à fonctionnalités imidazole ou imidazolium : nouveaux polydiacétylènes rouges analogues du poly-1, 6-bis(N,N-diphénylamino)-2, 4-hexadiyne." Montpellier 2, 2007. http://www.theses.fr/2007MON20210.

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CÃndido, Manuela Chaves Loureiro. "Study of the Reactivity of complex ions cis-[Ru (bpy)2(L) (NO)]n+ where L = imidazole, 1-metilimidazole, thiourea and sulfite." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7208.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
We carried out studies of chemical reactivity, electrochemistry and photochemistry of complexes cis-[Ru(bpy)2(L)(NO)](PF6)n, where L = imidazole, 1-methylimidazole, thiourea and sulfite. Were chosen, therefore, two ligands being  donors and two with ligands that act as -recipient and the results indicated that the nature and strength of these ligands directly influence the strength of the back donation between the metal center and coordinated nitric oxide. The infrared spectra showed a characteristic frequency of nitric oxide coordinated as NO+, and there was variation in the observed value of frequency of NO stretching, dependant of the auxiliary ligand. The results indicate that the backbonding between Ru and NO+ is stronger in the complex featuring the sulfite ligand in the coordination sphere, that complex having a minimum value to that specific stretching frequency, when compared to the other complexes. The experimental data corroborate with the Lever parameter values for the ligands, indicating the contribution of them to the electron density of the metal. The cyclic voltammetry performed in aqueous media indicate that the reduction of NO+ species to NO0 is facilitated with the increase of electron density donation from auxiliary ligands to the metallic center. And the differential pulse voltammetry indicates the possibility of the formation of aqueous-complex from a chemical reaction, after coordinated NO+ reduction. This work have shown that the photochemical release of nitric oxide from the light stimulation of complex solutions is consistent, even being possible to determine the species formed as a product of the photolysis and subsequent calculations of quantum yield of NO0 realese. Quantification of nitric oxide release was performed indirectly, using the technique of square wave voltammetry, which was efficient for the purpose. It was also used a selective electrode for free NO0 molecule, confirming that irradiation of NO+ compounds solutions actually cause the release of coordinated nitric oxide (NO+) to its active form in biological environment.
Neste trabalho foram realizados estudos de reatividade quÃmica, eletroquÃmica e fotoquÃmica dos complexos cis-[Ru(bpy)2(L)(NO)](PF6)n, onde L= imidazol, 1-metilimidazol, tiourÃia e sulfito. Foram escolhidos, portanto, dois ligantes auxiliares com caracterÃsticas  doadoras e dois com caracterÃsticas  receptoras e os resultados obtidos indicaram que a natureza e forÃa destes ligantes influenciam diretamente na retrodoaÃÃo existente entre o centro metÃlico e o Ãxido nÃtrico coordenado. Os espectros de infravermelho apresentaram freqÃÃncia caracterÃstica de Ãxido nÃtrico coordenado na forma NO+, sendo que houve variaÃÃo dos valores conforme a variaÃÃo do ligante auxiliar. Os resultados indicam que a interaÃÃo existente (retrodoaÃÃo) entre o Ru e o NO Ã mais forte para o complexo que apresenta o ligante sulfito na esfera de coordenaÃÃo, por apresentar um menor valor de freqÃÃncia de estiramento quando comparado aos demais complexos. Os dados experimentais corroboram com os valores do parÃmetro de Lever encontrados para os ligantes, que indicam a contribuiÃÃo dos mesmos para a densidade eletrÃnica do metal. Os ciclovoltamogramas, realizados em meio aquoso, indicam que a reduÃÃo da espÃcie NO+ a NO0 Ã facilitada quanto maior for a doaÃÃo de densidade eletrÃnica do ligante âLâ para o centro metÃlico. E a voltametria de pulso diferencial indica a possibilidade da formaÃÃo do aquo-complexo a partir de uma reaÃÃo quÃmica apÃs a reduÃÃo de Ãxido nÃtrico. Os estudos fotoquÃmicos mostraram que a liberaÃÃo de Ãxido nÃtrico a partir do estÃmulo luminoso de soluÃÃes dos complexos Ã consistente, sendo possÃvel inclusive a determinaÃÃo da espÃcie formada como produto da fotÃlise e posteriores cÃlculos de rendimento quÃntico da formaÃÃo das mesmas. A quantificaÃÃo da liberaÃÃo de Ãxido nÃtrico foi realizada de maneira indireta, utilizando a tÃcnica de voltametria de onda quadrada, que se mostrou eficiente para o objetivo. E foi utilizado tambÃm um eletrodo seletivo para a molÃcula de NO0 livre, confirmando que a irradiaÃÃo das soluÃÃes realmente leva a liberaÃÃo do Ãxido nÃtrico coordenado na sua forma ativa em meio biolÃgico.

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Pereira, Fernanda Antonia. "Estudo da interação do As(III) com modelo "zinc finger" da proteína NCp7 HIV-1 e complexos de Bi(III) e Sb(III) com ligantes contendo 2-mercapto-imidazol." Universidade Federal de Minas Gerais, 2010. http://hdl.handle.net/1843/SFSA-8DFJ9Z.

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The ejection of zinc from its coordination site in Zn-finger protein can be promoted by other metal species through competitive binding. This is considered as a promising strategy to inactivate the Zn-finger protein and for the design of new and more efficient drugs. A study of the As(III) interaction with the CCHC zinc finger domain of the NCp7 protein of HIV-1 has been carried out using the fluorescence and circular dichroism spectroscopies. This study allowed a better understanding of the ability of As(III) to promote Zn ejection and brought new insights into the role of glutathione as a biomolecule that can facilitate the ejection of Zn. The exactly mechanism is not yet known, but the fluorescence and circular dichroism data shows the importance of the participation of glutathione in the system formed. The competition between As(III) and Zn(II) was evaluated in phosphate buffers of different pHs. Sb(III) and Bi(III) compounds with 2-mercapto-imidazole- and -mercapto-benzimidazole-type ligands have been synthesized. These complexes involve coordination of the metal specie with the S-atom from thiol group and the N-atom from imidazole, just like occurs in the zinc finger domains. Five new complexes, SbCl(Bzmiz)2.CH3OH, BiCl(Bzmiz).CH3OH, BiCl2(Bzmiz).2H2O, SbCl2(Miz) and BiCl2(Miz) were successfully obtained. Physico-chemical characterization was performed using NMR, FTIR and UV-vis spectroscopies, elementar analyses, conductimetric analyses and thermogravimetric analyses. Four crystals were also obtained from these complexes, except for the SbCl2(Miz) complex. X-Ray diffraction analyses of these crystals are in course.
A ejeção do zinco promovida pela sua competição com outra espécie metálica pelo sítio de coordenação da proteína é tida como uma estratégia de inativação da proteína podendo possivelmente ser aplicada para síntese de novos fármacos mais eficazes. O estudo da interação do As(III) com modelo de peptídeo dedo de zinco CCHC da proteína NCp7 de HIV-1 foi realizado utilizando-se as técnicas espectroscópicas de fluorescência e dicroísmo circular. Esse estudo permitiu uma melhor compreensão sobre a habilidade do As(III) de promover a ejeção do Zn e o papel da glutationa como biomolécula facilitadora na ejeção do zinco. O exato mecanismo ainda não é conhecido, mas os dados de fluorescência e dicroísmo circular obtidos nos mostraram a importância da participação da glutationa no sistema formado. A competição entre As(III) e Zn(II) foi avaliada em diferentes pHs em tampão fosfato. Foram sintetizados compostos de Sb(III) e Bi(III) com os ligantes 2-mercapto-imidazol e 2-mercapto-benzimidazol. Os complexos envolvendo tais ligantes conservam como característica a coordenação da espécie metálica com S de grupo tiol e N de imidazol, assim como ocorre em domínios dedos de zinco. Obtivemos como resultados das sínteses, cinco complexos inéditos, bCl(Bzmiz)2.CH3OH, BiCl(Bzmiz).CH3OH, BiCl2(Bzmiz).2H2O, SbCl2(Miz) e BiCl2(Miz). A caracterização físico-química desses complexos foi feita por RMN, espectroscopias FTIR e UV-Vis, análises elementar (CHN), condutimetria e termogravimetria. Foram obtidos cristais de quatro dos cinco compostos sintetizados, não obtendo cristais apenas para o complexo SbCl2(Miz). Estudos de difração de raios X estão em andamento.

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Potvin, Marie-Eve. "Évaluation d'inhibiteurs au TGF-[bêta]1 chez la lignée cellulaire gliale maligne F98." Mémoire, Université de Sherbrooke, 2007. http://savoirs.usherbrooke.ca/handle/11143/3906.

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La protéine du TGF-[bêta]1 est une protéine multifonctionnelle qui agit dans plusieurs types cellulaires. Son action varie selon le type de cellulaire. Bien qu'elle ait un rôle inhibiteur chez les astrocytes normaux, elle posséderait un rôle principalement activateur de nombreuses voies carcinogéniques chez les tumeurs astrocytaires primaires malignes. L'isoforme du TGF-[bêta]1 est celle qui est la plus impliquée dans ces processus. Elle joue un rôle dans l'activation des voies d'invasion tissulaire et d'angiogenèse, mais inhibe des mécanismes d'apoptose et d'immunosuppression.La présente étude vise à évaluer l'effet de l'inhibition de la protéine du TGF-[bêta]1 sur le modèle cellules de glioblastome F98/Fischer sur la prolifération et la migration cellulaire. Pour ce faire, un inhibiteur sélectif au récepteur a d'abord été utilisé. Par la suite, des techniques d'inhibitions nucléotidiques (oligoantisens, siRNA, shRNA) ont été testées. Nous avons d'abord validé l'utilisation du modèle F98/Fischer dans l'étude des fonctions du TGF-[bêta]1 et de l'inhibition de la production de cette protéine. Nous avons observé la production importante de TGF-[bêta]1 par les cellules F98 avec des essais immunologiques (Western, ELISA). Avec l'essai ELISA, nous avons observé la production considérable de TGF-[bêta]1 actif d'emblée.La présence de notre protéine d'intérêt a été détectée dans le cerveau de rat Fischer implanté avec les cellules F98 contrairement aux animaux sains qui ne montrent aucune trace de TGF-[bêta]1. Ensuite, nous avons tenté de mettre au point une approche nucléotidique pour inhiber la production du TGF-[bêta]1. Pour les oligoantisens et les siRNA qui ont été couplés avec le vecteur liposomale Metafecten, nous n'avons pas réussi à obtenir de diminution significative du TGF-[bêta]1 dans les surnageants des cultures de F98 . Pour l'approche au shRNA/lentivirus, nous n'avons pas réussi à former de bactéries contenant la construction recherchée. Par la suite, nous avons testé sur notre modèle cellulaire un inhibiteur pharmacologique sélectif, le SB-431642, du récepteur permettant la phosphoryllation de la voie instracellulaire Smad, le T[bêta]R-I. Les essais de prolifération (WST-1) ont permis de constater un ralentissement dans la croissance des F98 traitées au SB-431542. Un essai immunologique western a permis de constater que la production de VEGF était d'ailleurs influencée par cette inhibition du TGF-[bêta]1. L'utilisation d'un vecteur luciférase couplé à un élément de réponse Smad a permis de constater que la voie du TGF-[bêta]1 était bel et bien affectée à la baisse par cet inhibiteur. En effet, le dosage luminescent de la luciférase a permis de noter une diminution significative de sa quantité. L'activité d'un tel vecteur est proportionnelle à l'activité Smad intracellulaire. Nous avons aussi testé cet inhibiteur sur le modèle de croissance tumorale tridimensionnelle de sphéroïdes F98.La croissance des sphéroïdes a été ralentie par la présence de l'inhibiteur et l'invasion de la matrice de collagène observée chez les sphéroïdes contrôles a été freinée par l'ajout de SB-431542. Bien que certains de nos essais n'aient pas donné les résultats escomptés, l'utilisation de l'inhibiteur SB-431542 nous a permis de voir l'implication à du TGF-[bêta]1 dans les mécanismes de progression tumorale chez la lignée cellulaire F98, tel que la prolifération et la migration cellulaire. Ces résultats sont le préalable à d'éventuels essais avec le modèle d'étude animal, le rat Fischer avec l'utilisation de cellules de glioblastomes F98.

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Qian, Zheng. "Analysis of DNA damage induced by 2-hydroxy amino-1-methyl-6-phenyl-imidazol [4,5-b] pyridine (N-OH-PHIP) in the mutation cluster region of the human APC gene." Available to US Hopkins community, 2002. http://wwwlib.umi.com/dissertations/dlnow/3068198.

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Oliveira, ?ngelo Anderson Silva de. "S?ntese e caracteriza??o do l?quido i?nico tetrafluoroborato de 1-metil-3-(2,6-(S)-dimetiloct-2-eno)-imidazol como eletr?lito para produ??o de hidrog?nio via eletr?lise da ?gua." Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12992.

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Made available in DSpace on 2014-12-17T14:08:55Z (GMT). No. of bitstreams: 1 AngeloASO_DISSERT.pdf: 1949187 bytes, checksum: e1a09a3868062ecaf1e44bef8c6c67fb (MD5) Previous issue date: 2013-11-18
Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
Ionic liquids (ILs) are organic compounds liquid at room temperature, good electrical conductors, with the potential to form as a means for electrolyte on electrolysis of water, in which the electrodes would not be subjected to such extreme conditions demanding chemistry [1]. This paper describes the synthesis, characterization and study of the feasibility of ionic liquid ionic liquid 1-methyl-3(2,6-(S)-dimethyloct-2-ene)-imidazole tetrafluoroborate (MDI-BF4) as electrolyte to produce hydrogen through electrolysis of water. The MDI-BF4 synthesized was characterized by thermal methods of analysis (Thermogravimetric Analysis - TG and Differential Scanning Calorimetry - DSC), mid-infrared spectroscopy with Fourier transform by method of attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance spectroscopy of hydrogen (NMR 1H) and cyclic voltammetry (CV). Where thermal methods were used to calculate the yield of the synthesis of MDI-BF4 which was 88.84%, characterized infrared spectroscopy functional groups of the compound and the binding B-F 1053 cm-1; the NMR 1H analyzed and compared with literature data defines the structure of MDI-BF4 and the current density achieved by MDI-BF4 in the voltammogram shows that the LI can conduct electrical current indicating that the MDI-BF4 is a good electrolyte, and that their behavior does not change with the increasing concentration of water
Os l?quidos i?nicos (LIs) s?o compostos org?nicos l?quidos ? temperatura ambiente, bons condutores el?tricos, com potencial para constitu?rem como meio eletr?lito para a eletr?lise da ?gua, no qual os eletrodos n?o seriam submetidos a condi??es t?o extremas de exig?ncia qu?mica [1]. O presente trabalho descreve a s?ntese, a caracteriza??o e o estudo da viabilidade do l?quido i?nico tetrafluoroborato de 1-metil-3(2,6-(S)-dimetiloct-2-eno)-imidazol (MDI-BF4) como eletr?lito para a produ??o de hidrog?nio atrav?s da eletr?lise da ?gua. O MDI-BF4 sintetizado foi caracterizado por: m?todos t?rmicos de an?lise (An?lise Termogravim?trica - TG e Calorimetria Explorat?ria Diferencial - DSC); espectroscopia de infravermelho m?dio com transformada de Fourier pelo m?todo da reflect?ncia total atenuada (FTIR-ATR); espectroscopia de resson?ncia magn?tica nuclear de hidrog?nio (RMN 1H) e voltametria c?clica (VC). Onde os m?todos t?rmicos foram utilizadas para calcular o rendimento da s?ntese do MDI-BF4 que foi de 88,84 %; a espectroscopia de infravermelho caracterizou os grupos funcionais do composto e a liga??o B-F em 1053 cm-1; o RMN 1H analisado e comparado com dados da literatura define a estrutura do MDI-BF4 e a densidade de corrente alcan?ada pelo MDI-BF4 no voltamograma mostra que o LI consegue conduzir corrente el?trica indicando que o MDI-BF4 ? um bom eletr?lito e que seu comportamento n?o sofre altera??o com o aumento da concentra??o de ?gua

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Gosling, Sandrine. "Synthèse et fonctionnalisation de 2-thiohydantoïnes : interaction et inhibition des nucléosides monophosphate kinases." Thesis, Orléans, 2011. http://www.theses.fr/2011ORLE2028/document.

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La découverte de nouvelles substances thérapeutiques nécessite la synthèse de série de molécules soumises au criblage biologique sur une cible donnée. Ce projet de recherche a pour objectif de développer des inhibiteurs de nucléosides monophosphate kinases (NMPK) en se basant sur le concept de chimie dynamique combinatoire in situ. La synthèse de ces molécules a nécessité l’association via des fonctions réactives d’un analogue d’accepteur de phosphate et d’un mime d’ATP donneur de phosphate. La mise au point de ce dernier a fait l’objet de ce travail de thèse et a été orientée vers la pharmacomodulation d’un hétérocycle azoté et soufré: la 2-thiohydantoïne. La synthèse de ce composé a été réalisée par la méthode de Schlack-Kumpf et par celle d’Edman provenant de techniques d’analyses peptidiques. Ces deux voies ont été exploitées pour étudier la réactivité et la fonctionnalisation sélective de cet hétérocycle notamment par des couplages de type Suzuki. La réaction de Vilsmeier-Haack-Arnold a par la suite constitué l’étape clé permettant de transformer un cycle 2-thiohydantoïne en un cycle de type imidazole qui a pu être fonctionnalisé en diverses positions. La synthèse de dérivés 2-thiohydantoïne et imidazole diversement substitués par des groupements utiles, au couplage in situ avec les analogues d’accepteur de phosphate ainsi qu’à l’affinité enzymatique a permis l’accès à une bibliothèque de molécules. Des tests biologiques ont permis d’évaluer leur affinité vis-à-vis de plusieurs NMPK ainsi que leur cytotoxicité sur cellules cancéreuses ; cet ensemble de résultats permettant de trouver les déterminants nécessaires à l’activité biologique
New therapeutical compounds determination requires the formation of a library of molecules and their screening on specific biological targets. The aim of this project was to design new inhibitors targeting nucléoside monophosphate kinases (NMPK) based on in situ dynamic combinatorial chemistry. These molecules were synthesized by ligation between analogues of phosphate acceptors and donors on which reactive functions were introduced. The topic of this PhD was to develop the ATP mimetics using chemical transformation and pharmacomodulation of a small heterocycle: 2-thiohydantoin. Its synthesis was achieved using the Schlack-Kumpf and the Edman methods initially develop for peptidic analysis. These two pathways have been explored in order to study the reactivities and the selective functionalizations of the heterocycle allowing for example Suzuki cross coupling reactions. Furthermore we used the Vilsmeier-Haack-Arnold reaction as a key step to the formation of a highly substituted imidazole ring directly from a 2-thiohydantoin. The synthesis of 2-thiohydantoin and imidazole derivatives, on which reactive groups for the in situ coupling reactions and the enzymatic affinity have been introduced, leads to a library of molecules. Their affinity toward to ATP donor site of NMPK and their toxicity on cancer cells were evaluated by biological tests

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Ciccolini, Cecilia. "Synthesis of Mono and Poly-Heterocycles starting from 1,2-Diaza-1,3-Dienes (or precursors) as Building Blocks." Doctoral thesis, Urbino, 2020. http://hdl.handle.net/11576/2674162.

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Tholé, France. "Étude d'une synthèse totale énantiosélective et convergente des liposidomycines." Paris 6, 2002. http://www.theses.fr/2002PA066352.

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Renaud, Jean-Paul. "Oxydations d'alcanes et d'alcènes par des systèmes métalloporphyriniques modelés du cytochrome P-450." Paris 6, 1986. http://www.theses.fr/1986PA066139.

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La synthèse d'une pophyrine de fer à "anses de panier" chirale comportant des aminoacidés de configuration déterminée est décrite. On a étudié sa pureté optique et sa conformation en solution. Dans une deuxième partie on décrit un nouveau système oxydant catalytique utilisant l'eau oxygénée en présence d'une porphyrine de manganèse et d'imidazole permettant la conversion quantitative d'alcènes en époxydes et d'alcanes en alcools et cétones.

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Yang, Chun-Ting, and 楊君鼎. "Synthesis of (5-methyl-2-furyl) imidazo [4,5-b]pyridine Derivatives as Antiplatelet Agents." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/61659545056673902803.

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碩士
中國醫藥大學
藥物化學研究所碩士班
100
In continuing development of novel aniplatelet agents, we had found that 1-benzyl-2-(5-methyl-2-furyl)benzimidazole ( I ) showed good platelet inhibitory activity. Compound I showed good inhibitory effect on the platelet aggregation induced by collagen、arachidonic acid、U46619. Encouraged by this result,the Compound I was selected as a lead compound and a series of 5(or 6)-halo-1-substituted benzyl-2-(5-methyl-2-furyl)imidazo[4,5-b]pyridine (3~40) were synthesized in this work. All the synthesized compounds were evaluated for their antiplatelet activities. In this article, we aim at synthesizing and evaluating their antiplatelet activities. Some of the target compounds showed the same pattern as compound I and exhibited highly inhibitory activity against platelet aggregation induced by collagen. Compound 30 also showed good inhibitory effects on platelet aggregation induced by U46619(10μM). The finding will add to our understanding of SAR of benzimidazoles. The gole of our continuing studies is to identify novel compounds for antiplatelet study.

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45

Abu-Rayyan, Ahmed [Verfasser]. "Synthese von organischen und anorganischen Derivaten der Imidazol-2-ylidene und 2-Methylenimidazoline = Synthesis of organic and inorganic derivatives of imidazol-2-ylidenes and 2-methyleneimidazolines / vorgelegt von Ahmed Abu-Rayyan." 2005. http://d-nb.info/975795023/34.

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46

Chiu, Ying-Chang, and 邱盈彰. "Metallomesogens based on N-(2-hydroxy)alkyl substituted imidazole derivatives." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/24548624483347290155.

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博士
國立東華大學
化學系
97
Metallomesogens of the types (i) N-(2-hydroxyl)alkyl imidazole coordinated with Silver(I), Gold(I), and Palladium(II) ions (in Chapter II), (ii) Silver(I) and Gold(I) complexes of N-hexadecanyl-N´-(2-hydroxyhexadecanyl) imidazol-2-ylidenes (in Chapter III), and (iii) nanocomposites of Gold nanoparticles embedded in N,N´-di-substituted imidazolium salt (in Chapter IV) are presented. The characterizations, results, and discussions are described in each section.

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47

Turnbull, Stanhope P. "Study of bis-imidazol-2-yldines as ligands for transition metal catalyzed coupling reactions." 2004. http://louisdl.louislibraries.org/u?/NOD,189.

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Thesis (Ph. D.)--University of New Orleans, 2004.
Title from electronic submission form. "A dissertation ... in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Department of Chemistry."--Dissertation t.p. Vita. Includes bibliographical references.

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48

Liu, Yuan, and 劉媛. "The anti-proliferation effect of 2-(Naphthalen-2-ylmethylsulfanyl)-5,5-diphenyl-1,5-dihydro-imidazol-4-one（SDil-N10）in human vascular endothelial cells." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/27079856038903848465.

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碩士
臺北醫學大學
醫學研究所
92
The aim of this study was to examine the anti-proliferation effect of 2-(Naphthalen-2-ylmethylsulfanyl)-5,5-diphenyl-1,5-dihydro- imidazol- 4-one (SDil-N10), an analogue of antiepileptic drug phenytoin(5,5- diphenylhydantoin, DPT), on human umbilical vein endothelial cells (HUVEC) and its possible molecular mechanism underlying. SDil-N10 at a range of concentrations (10-50 uM) dose- and time-dependently inhibited DNA synthesis and decreased cell number in cultured HUVEC, but less effect in human fibroblasts. [3H] Thymidine incorporation assay demonstrated that treatment of HUVEC with SDil-N10 arrested the cell at the G0/G1 phase of the cell cycle. Western blot analysis revealed that the protein levels of p21 and p27 increased and cyclin A decreased after SDil-N10 treatment. In contrast, the protein levels of p53, cyclin D1, D3 and E, cyclin-dependent kinase (CDK2, and CDK4) in HUVEC were not changed significantly after SDil-N10 treatment. Immunoprecipitation showed that the formation of the CDK2-p21 complex, but not the CDK4-p21, CDK2-p27 and CDK4-p27 complex, was increased in the SDil-N10-treated HUVEC. Kinase assay further demonstrated that CDK2, but not CDK4, kinase activity was decreased in the SDil-N10-treated HUVEC. SDil-N10 also inhibited vascular endothelial growth factor (VEGF) induced endothelial cells proliferation. 2D-Matrigel and rat aorta tube formation assays further showed that SDil-N10 inhibited HUVEC tube formation. Taken together, these data suggest that SDil-N10 inhibits HUVEC proliferation by increasing the level of p21 protein, which in turn inhibits CDK2 kinase activity, and finally interrupts the cell cycle. The findings from the present study suggest that SDil-N10 might have the potential to inhibit the occurrence of angiogenesis.

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49

Chlang, Shu-Wei, and 江書瑋. "Synthesis and Characterization of 2-Phenyl-1H-benzo[d]imidazole Iridium Metal Complexes." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/66836780097092907548.

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碩士
正修科技大學
化工與材料工程研究所
95
This study synthesizes a series of Imidazol derivative, and it coordinate with the iridium metal to form a series of iridium metal complexes. change the iridium metal complexes emission color and carry on discussions of physical optics property to the iridium metal complexes. The absorption spectra of these compounds showed intense bands appearing in the ultraviolet or near ultraviolet part of the spectrum between 250 and 420 nm, emission spectra show from 300 nm to 500 nm, colors of emission are from blue.After the ligands and metals coordinate to form iridium metal complexes, their color of emission from Yellow to red, emission spectra show from 450 nm to 750 nm.

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50

Chiang, Wen-Ta, and 蔣文達. "Liquid crystals derived from N-alkyl 2-hydroxyl imidazole complexes of palladium and gold." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/21434102075868195544.

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