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1

Brice, Heloise. "Dearomatising cyclisations onto pyridines". Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496237.

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This thesis details investigations into the dearomatising cyclisation onto pyridines. Studies into the cyclisation of enolate or silyl enol ether nucleophiles onto a pyridine ring are described. Flexible hydrocarbon tethers and tethers incorporating either an oxygen or nitrogen atom were investigated and novel fused 6.5 and 6.6 bicyclic piperidines have been synthesised. A one-pot silyl enol ether or silyl ketene acetal formation and cyclisation procedure has been developed.
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2

Altuna-Urquijo, M. "New routes to functionalised pyridines". Thesis, Northumbria University, 2005. http://nrl.northumbria.ac.uk/3327/.

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A novel method of preparing substituted pyridines has been developed. This method uses readily available [3-ketoesters and amidrazone as starting materials. The pyridines obtained do not require purification and different substitution patterns, not available by known methods, can be obtained. The formation of 1,2,3-tricarbonyl compounds was achieved by oxidation of the alcohol precursors, following two different methods. a-Chloro-ct-acetoxy-f3-dicarbonyls were prepared in excellent yields and were shown to react as tricarbonyl equivalents in the formation of 1,2,4-triazines. Regioselective condensation reactions were observed between different amidrazones with tricarbonyl and tricarbonyl equivalents to produce a series of novel 1,2,4-triazines in good yields with no contamination by any regioisomer. When 1,2,4-triazines were obtained from a-chloro-a-acetoxy-P-dicarbonyls, 2.5 equivalents of amidrazone were required. However, decomposition of a-chloro-a-acetoxy-P-dicarbonyls prior to reaction with 1 equivalent of amidrazone yielded the 1,2,4-triazines in good yields. These 1,2,4-triazines underwent aza Diels-Alder cycloaddition reactions with 2,5- norbornadiene to give a series of novel 2,3,6-trisubstituted pyridines. The pyridines bearing electron withdrawing groups as substituents could also be obtained in a 'one- pot' reaction from their corresponding tricarbonyls or tricarbonyl derivatives. The 1,2,4- triazines bearing electron donating groups could be converted to their corresponding pyridines either by changing the reaction conditions or, when possible, by conversion of the electron donating group into a more electron withdrawing substituent by oxidation (e.g. sulphoxide substituent). Pyridines bearing a sulphoxide substituent undergo nucleophilic substitutions, giving great scope to introduce different functionality in the C-6 of the pyridines.
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3

Harrington, Keith Anthony. "Regioselective synthesis of functionalised pyridines". Thesis, University of Leeds, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329948.

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4

Bouteau, Brigitte. "Synthèse et étude physicochimique de pyrrolyl-pyridines, pyrido (2,3-c) pyrrolo (1,2-e) triazépines-1,2,5, triazolo-1,2,4 (4,5-a) pyridines, triazolo (1,2,4) (2,3-a) pyridines". Caen, 1989. http://www.theses.fr/1989CAEN4051.

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5

Cadu, Alban. "Iridium Catalysed Asymmetric Hydrogenation of Pyridines". Licentiate thesis, Uppsala universitet, Syntetisk organisk kemi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-212413.

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This thesis presents the hydrogenation of substituted pyridines using N,P-ligated iridium catalystsin homogeneous media. These iridium catalysts were developed within this research group in thepast decade. This method of hydrogenation is highly stereoselective, and in several cases good to excellent ees were obtained.The hydrogenation of substituted pyridines was studied: by screening for the catalyst giving thehighest conversion and ee, by optimising the reaction conditions and by attempting to improve existingcatalysts. New substrates were synthesised for this process, in particular alkyl substituted Nprotectedpyridines. Their reduction provided chiral piperidines, which could be used as chiralbuilding blocks once deprotected.
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6

McConnell, Stuart. "2-functionalised pyridines with transition metals". Thesis, Queen Mary, University of London, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243479.

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7

Mace, Laura H. "Developing the partial reduction of pyridines". Thesis, University of Oxford, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398101.

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8

Gehre, Alexander. "Development of novel routes to pyridines". Thesis, Northumbria University, 2008. http://nrl.northumbria.ac.uk/3533/.

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Pyridines occupy a central part in modern day organic chemistry. Recent studies in various fields of chemistry, biology and physics have featured numerous examples and applications of these compounds. The purpose of this study was to produce a library of polysubstituted pyridines, 2,2'-bipyridines and 2,2':6',2"-terpyridines via pathways that allowed unusual or even unique substitution patterns. To achieve a generic pyridine synthesis that delivers a diversity of products tailored to different industrial needs, a strategy by which the target molecule is constructed in a [2+2+2]-manner was chosen, i.e. the six atoms of the pyridine ring and their pendant functionalities are traced back to three building blocks, each delivering two atoms to the pyridine ring. A range of a-acetoxy-a-chloro-P-keto esters were prepared in three steps from commercially available P-keto esters through a-chlorination with sulfuryl chloride, a-acetoxylation with acetic acid and triethylamine and a second a-chlorination in good overall yields (69 — 89 %) without the need for chromatographic purification. These a-acetoxy-a-chloro-j3-keto esters served as equivalents for a,[3-diketo esters (building block 1) in the synthesis of various 1,2,4- triazines through condensation with picolinohydrazonamides or thiosemicarbazides (building block 2). A subsequent aza Diels-Alder reaction of these 1,2,4-triazines with electron-rich dienophiles (building block 3) such as 2,5-norbornadiene, 1-pyrrolidino- 1 -cyclopentene and 2,3-dihydrofuran furnished an array of novel polysubstitued (bi)pyridines. The two-step sequence of condensation and aza Diels-Alder reaction could be advanced into a 'one-pot' synthesis on several occasions. Furthermore, we devised a feasible synthetic alternative towards a,(3-diketo esters. Alpha-picolinoyl-3-keto esters were prepared from the same starting materials as the a-acetoxy-a¬chloro-P-keto esters in a shortened two-step sequence of a-chlorination of P-keto esters with sulfuryl chloride and replacement of the chloro group by a picolinoyl group using picolinic acid and KHCO3. The overall yields of a-picolinoyl-f3-keto esters (55 — 91 %) were comparable to those of the a-acetoxy-a-chloro-P-keto esters. Copper(II) acetate-facilitated methanolysis of a-picolinoyl-P-keto esters and immediate oxidation of the in situ generated a-hydroxy-P-keto esters by excess copper(II) acetate afforded a,(3-diketo esters which reacted with hydrazonamides in the same manner as the a-chloro-a-acetoxy-P-keto esters. However, in terms of product purity and yield the `chloroacetate route' remains the superior strategy.
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9

Chen, Quan. "BF3-mediated direct functionalizations of pyridines". Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-175551.

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10

Galley, Carl Maurice Swedler. "Some chemistry of pyridines and pyridones". Thesis, University of Bristol, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.412833.

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11

Poderi, Cecilia. "Synergistic catalysis: Michael addition of acyl-pyridines". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/14409/.

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A new diastereo- and enantioselective strategy for the functionalization of 2-acetyl-pyridine with α,β-unsaturated aldehydes has been investigated through synergistic catalysis. In particular, the aim of the work was to use cinnamaldehydes bearing different substituents on the phenyl group and to study its effect on the yield, conversion and stereoselectivity of the reaction. The reaction mechanism involves combined iminium ion and transition metal catalysis in a synergistic fashion and proceeds with two consecutives Michael additions, followed by final intramolecular aldol condensation to yield the formation of three new stereogenic carbons, with high to excellent stereoselectivities. The structures of the molecules obtained were fully characterized by NMR spectroscopy. After having assigned the relative configuration by NOE-NMR and 2D-COSY experiments, conformational analysis was performed by DFT calculations to find the most stable molecular conformations. The absolute configuration of each diastereoisomer was then eventually assigned by quantum mechanical simulations of the Electronic and Vibrational Circular Dichroism spectra.
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12

Brotzel, Frank. "Nucleophilicities of Amines, Amino Acids and Pyridines". München : Verl. Dr. Hut, 2008. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=017069126&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.

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13

Tandon, Raman. "Tailor-Made highly nucleophilic pyridines for organocatalysis". Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-157028.

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14

Moon, Maria-Teresa. "The functionalisation of pyridines : studies towards dysiherbaine". Thesis, University of Bristol, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.399919.

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15

Paina, Federica. "De novo synthesis of highly substituted pyridines". Thesis, Imperial College London, 2008. http://hdl.handle.net/10044/1/1243.

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This thesis is divided into three chapters. Chapter 1 provides a brief survey of the methodologies currently available for the de novo synthesis of cyclopentadienes. Particular relevance is given to the more general methods and to the preparation of structurally interesting compounds. Mechanistic details will also be given for interesting or unusual reaction pathways. Chapter 2 presents research findings in the field of the application of the decarboxylative Claisen rearrangement (dCr) reaction to the synthesis of aromatics. The development of a novel methodology for the preparation of substituted pyridines will be described. Firstly, the feasibility of the method will be shown by detailing the preparation of simple pyridines, carrying alkyl and aryl substituents. Subsequently, efforts to expand the scope of the methodology will be discussed and attempts to prepare diversely substituted, chiral and cyclofused compounds detailed. Finally, some preliminary results concerning the use of the dCr reaction for the synthesis of cyclopentadienes and cyclopentadienyl anions will be presented. Chapter 3 provides the experimental details and the characterisation data for all the compounds synthesised.
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16

Rizk, Toni. "Synthesis of pyridines and pyrazines using intramolecular hydroamination". Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28453.

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Despite recent progress, the scope and efficiency of intramolecular hydroamination has not yet reached its full synthetic potential. In particular, cyclizations to form 6-membered rings and applications in the synthesis of aromatic nitrogen heterocycles remain rare, despite the potential to access a variety of medicinally relevant heterocycles. The intramolecular hydroamination of alkynes presented offers a general approach to such nitrogen heterocycles from appropriately substituted acyclic precursors, in which the oxime functionality allows for a milder cyclization event and allows subsequently for the installation of one additional unsaturation (via loss of H2O). The discovery and optimization of an acid-catalyzed, hydroamination-isomerization-aromatization route for the synthesis of pyridines and pyrazines will be presented and discussed.* *Please refer to dissertation for diagrams.
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17

Johnson, Dale James. "Investigations into the partial reduction of substituted pyridines". Thesis, University of Oxford, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442830.

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18

Healy, Maureen A. M. "Electrocyclic approaches to fused pyridines and 12-azasteroids". Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316557.

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19

Sutton, Benjamin Josiah. "Intramolecular radical additions to pyridines, quinolines and isoquinolines". Thesis, University of Southampton, 2003. https://eprints.soton.ac.uk/426728/.

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20

Véron, Jean-Baptiste. "Synthèse d'imidazo[1,2-α]pyridines à activité antivirale". Tours, 2006. http://www.theses.fr/2006TOUR3807.

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Le motif imidazo[1,2-a]pyridine fait actuellement l’objet d’un regain d’intérêt de la part du monde de la recherche thérapeutique. Ceci s’explique en partie par les progrès réalisés dan s le domaine des couplages métallo-catalysés qui ont permis de lever les difficultés de fonctionnalisation associées au motif imidazo[1,2-a]pyridinique. Les travaux de cette thèse ont porté sur deux projets distincts : La synthèse d’imidazo[1,2-a]pyridines présentant une activité antivirale vis-à-vis de certains herpesvirus mais également du virus de l’hépatite C (VHC) et du virus de la diarrhée virale bovine (BVDV). Les travaux de cette thèse ont consisté à appliquer diverses méthodes de couplages afin de fonctionnaliser les positions 6 et 8 d’imidazo[1,2-a]pyridines comportant une chaî ; ne thioether en position 3. L’activité biologique des composés préparés a été évaluée vis-à-vis de nombreux virus (notamment le CMV et le VZV). D’autre part, une étude de pharmacomodulation a été entreprise sur des dérivés de l’imidazo[1,2-a]pyridine et de l’imidazo[1,2-b]pyridazine comportant un motif aromatique en positions 3 et diversement substitués en position 6. L’activité de ces composés a été évaluée vis-à-vis du VHC et du BVDV. La synthèse d’imidazo[1,2-a]pyridines, ligands des récepteurs benzodiazépiniques périphériques (PBR) en collaboration avec Sanofi-Aventis. Ces molécules, diversement substitu&e a cute;es en position 2 et 3 ont été préparées selon les méthodes de couplages métallo-catalysés mises au point au laboratoire. L’influence des substituants portés par le groupement en position 3 a été étudiée. L’affinité de ces composés pour PBR a ensuite été évaluée
The imidazo[1,2-a]pyridine moeity is currently the object of a renewed interest in therapeutic research. This is mostly due to recent progesses in metallocatalyzed couplings which allow easier and wider functionnalization of the imidazo[1,2-a]pyridine moiety. This thesis is divided in two parts : The synthesis of imidazo[1,2-a]pyridines with antiviral activity against some herpes viruses but also against hepatitis C virus (HCV) and bovine viral diarrhea virus (BVDV). The present work consisted in the application of various coupling methods in order to functionalized the 6 and 8 positions of imidazo[1,2-a]pyridines carrying a thioether chain in 3 position. The biological activity of these compounds was measured upon many viruses (like CMV and VZV). Futhermore, a pharmacomodulation study was made on imidazo[1,2-a]pyridine and imidazo[1,2-b]pyridazine derivatives carrying an aromatic moiety in 3 position and variously substituted in 6 position. The activity of theses compounds was evaluated against HCV and BVDV. The synthesis of imidazo[1,2-a]pyridines, ligands of peripheral benzodiazepine receptors (PBR) in collaboration with Sanofi-Aventis. The molecules, variously substituted in 2 and 3 positions were prepared using metallo-catalyzed coupling methods developed at the laboratory. The influence of the 3 position substituents was studied and the PBR affinity of our compounds measured
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21

Sturrock, Keith. "Synthesis and reactions of some pyridines and thienopyridines". Thesis, Abertay University, 2005. https://rke.abertay.ac.uk/en/studentTheses/cc5042b3-b728-4302-909b-3a78323015b1.

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The overall aim of this research project is to investigate nucleophilic substitution reactions of the thiomethyl group of 3-ethyloxycarbonyl-2-methylthiothieno[2,3-b]jpyridine. The multistep synthesis of this compound is reviewed and improvements described. The first step is the N-oxidation of ethyl 3- pyridylacetate, so reagents for the preparation of this and other 3-substituted pyridines were investigated and a novel workup procedure for oxidation with m-CPBA (m-chloroperbenzoic acid) is described. The preparation of ethyl 2-chloro-3-pyridylacetate and several polychlorinated pyridine derivatives are reported. Novel ketene dithioacetals were prepared from ethyl 5-chloro-3-pyridylacetate and 5-chloro-3-pyridylacetonitrile and some were converted to highly substituted thiophenes. Novel thieno[2,3-b]pyridines and [3,2-c]pyridines were prepared from ethyl 2-chloro-3-pyridylacetate, ethyl 4-chloro-3-pyridylacetate and their N-oxides. Preparation of the sulphoxide and sulphone of 3-ethyloxycarbonyl-2- methylthiothieno[2,3-b]pyridine was investigated and their relative susceptibility to substitution by some nitrogen nucleophiles examined. The conversion of benzylamine to benzaldehyde by the N-oxide group during the reaction of 3-ethyloxycarbonyl-2-methylthiothieno[2,3-b]pyridine N-oxide with benzylamine was studied in some detail. Attempts were made to develop a synthetic route to the potential agonist of serotonin, 3-(2-aminoethyl)-5-hydroxythieno[2,3-b]pyridine from 3-ethyloxycarbonyl-2-methylthiothieno[2,3-b]pyridine. Successful removal of the thiomethyl group at C-2 of 3-ethyloxycarbonyl-2-methylthiothieno[2,3- bjpyridine and progress made in development of the side chain at C-3 is reported. This thesis exhibits evidence of clear progress towards the development of a novel synthetic route to potential agonists of serotonin.
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22

Kemmitt, Paul D. "Fused pyridines by electrocyclic ring closure of 1-azatrienes". Thesis, University of Liverpool, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359439.

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23

Thapa, Rajesh. "Regioselectivity in Free Radical Bromination of Unsymmetrical Dimethylated Pyridines". Miami University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=miami1263340046.

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24

Bachollet, Sylvestre. "Regiocontrolled routes to substituted pyridines via directed cycloaddition reactions". Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/15887/.

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New strategies have been investigated for the synthesis of highly substituted pyridine rings via inverse electron demand aza-Diels-Alder reactions of 1,2,4-triazines with alkynes. The synthesis of pyridines via cycloaddition/retro-cycloaddition strategies has largely focused on the use of enamine dienophiles as alkyne surrogates, as alkynes themselves only participate in [4+2] cycloadditions with triazines under very harsh conditions. Moreover, such processes usually provide the products in low yields and regioselectivities. To tackle these drawbacks, we were interested in a directed cycloaddition concept where 1,2,4-triazines were reacted with alkynyltrifluoroborate salts in the presence of a Lewis acid to form pyridines possessing a boron moiety offering further synthetic opportunities. The generated Lewis acidic alkynes, containing a “BF2” moiety, were then used in conjunction with triazines equipped with a Lewis base (such as a pyridine or an amide). Coordination of the two partners lowered the overall energy needed for the cycloaddition to take place and the corresponding pyridines were obtained within 10 minutes at 40 °C with complete regiocontrol. Organoboranes are a widely employed fluorophore family because of their excellent optical properties and their conveniently variable emission wavelength. The tetravalent boron found in the borylated bipyridines products (BOBIPYs) formed via our previously developed methodology prompted us to investigate their optical properties. These proved to comprise a new family of fluorophores showing blue to green fluorescence with quantum yields up to 41%. A series of compounds was synthesized and interrogated via DFT calculations and photophysical measurements. Streptonigrin, an antitumor and antibiotic agent, has drawn considerable attention from synthetic organic chemists because of its challenging structure, containing a highly substituted pyridine core. To date, only two groups achieved its total synthesis, and two more reached a formal synthesis. We established a succinct formal synthesis of streptonigrin, establishing the practical advantages of our cycloaddition methodology.
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25

Björk, Malin. "Synthesis of sulfur and seleniumn heterocycles, including derivatives of imidazopyridine and benzimidazole /". Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-597-6/.

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26

Doebelin, Christelle. "Application des réactions pallado-catalysées à la synthèse de ligands de RCPGs de neuropeptides (NPFF1/2, GPR54) : pepetidomimétiques et dérivés polysubstitués de pyridine". Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAF046/document.

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Les récepteurs du neuropeptide FF (NPFF) et GPR54 font partie d’une sous-famille de récepteurs couplés aux protéines G (RCPG) de neuropeptides, qui présentent dans la partie C-terminale une même séquence Arg-Phe-NH2. Ce motif dipeptidique a servi initialement à concevoir des ligands nanomolaires des R-NPFF. Cette même approche a été reprise pour développer des ligands agonistes de GPR54 en optimisant la partie N-terminale du dipeptide (synthèse de dérivés de N-(4-phénylacétylen) phénylcarbonyl Arg-Trp-NH2 par une réaction de Sonogashira sur support solide). Plusieurs composés peptidomimétiques de la séquence Arg-Phe ont aussi été synthétisés (gemdiaminals, pipérazinones, imidazole 4-carboxamides, indole-2-carboxamides). Certains d’entre eux ont montré une affinité comparable à celle de leurs analogues en série dipeptides. Un dérivé de 2-N-acylamino-3-cyanopyridine a été identifié comme hit, puis optimisé par les chercheurs des laboratoires Takeda. Ce composé se lie puissamment et sélectivement à GPR54 (Ki~5nM). Cependant le mode d’interaction de cette pyridine polyfonctionnelle n’est pas connu, et a nécessité la mise au point de nouvelles approches faisant appel aux réactions pallado-catalysées(Suzuki-Miyaura, Sonogashira, Buchwald-Hartwig). L’analyse RSA conduit à l’hypothèse d’un mode d’interaction complexe mettant en jeu un système électronique particulier incluant un cortège de liaisons hydrogène intramoléculaires impliquant l’azote sp2 de la pyridine, les deux groupements accepteurs-donneurs de liaison hydrogène en position 2 et 6 et le groupe cyano en position 3. La stratégie méthodologique développée dans le cadre du projet pharmacochimique a pu être appliquée avec succès pour la première synthèse connue à ce jour d’une pyridine pentasubstituée portant cinq aromatiques différents, et nécessitant un contrôle régiosélectif et séquentiel de cinq réactions de Suzuki-Miyaura. Cette approche est modulable et pourra être appliquée à la synthèse de nouvelles pyridines polysubstituées/fonctionnalisées pour la synthèse de nouveaux pharmacophores
Neuropeptide FF (NPFF) receptors and GPR54 belong to a sub-class of G protein coupled receptors (GPCR’s) of neuropeptides containing in their C-terminal part the same dipeptidic Arg-Phe-NH2 fragment. This motif served initially for designing nanomolar ligands of NPFF-R. A similar approach was also used in this work for developing agonists dipeptides acting at GPR54, after structural optimization of the dipeptide N-acyl part (solid phase synthesis of N-(4-phenylacetylen)phenylcarbonyl Arg-Trp-NH2 by Sonogashira reaction). Several series of Arg-Phe peptidomimetics were also synthesized (gem-diaminals, piperazinones, imidazol-4-carboxamides, indol-2-carboxamides). Some of them presented affinity profiles similar to those obtained with the corresponding N-acyl RFamides. A non peptidic compound deriving from 2-N-acylamino-3-cyanopyridine was recently identified as a hit, which was further optimized by Takeda laboratories. This compound binds potently to GPR54 (Ki~5nM). However the mode of interaction of this polyfunctional pyridine within the active site of GPR54 is poorly understood. We investigated more structural analogues by means of palladocatalyzed reactions (Suzuki-Miyaura, Sonogashira, Buchwald-Hartwig). SAR analysis highlighted a complex mode of interaction of this series of compounds, involving a set of intramolecular hydrogen bond acceptor-donor systems between pyridine sp2 nitrogen, and the two fragments on position 2 and 6 of the pyridine. In addition the cyano group may be also involved as inducer of a specific electronic current along the main core of the molecule. The strategy developed for the design and synthesis of novel ligands deriving from pyridine could also be applied with success for the first synthesis known to date of a pentasubstituted pyridine bearing five different aromatic rings by means of a five Suzuki-Miyaura reactions. This approach is versatile and will be applied in the future for providing novel polysubstituted/functionalized pyridinecompounds as novel pharmacological agents
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27

Gerhardt, Warren William. "Towards Supramolecular Multifunctional Architectures". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14619.

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The synthesis of new biological and polymeric supramolecular synthons and their assembly into unique supramolecular architectures is presented. These new supramolecular synthons are functionalized with ligands that compliment metallated pincer complexes. Through the use of ditopic metallated pincer complexes these supramolecular synthons can be self-assembled into infinite linear chains. The first class of supramolecular synthons synthesized were based on cyclic peptide units, by embedding a pyridyl unit into the side-chain of one of the peptide residues the cyclic structure can be coordinated to a metallated pincer complex. It is proposed that these supramolecular architectures may be further enhanced by incorporating multiple pyridyl units along the cyclic peptide backbone and coordinating them through multitopic pincer complexes to give porous membrane structures. The second class of supramolecular synthons is based on photoluminescent X-shaped cruciform molecules. By terminating one axis with pyridyl moieties these units may be assembled into fluorescent coordination polymers with good solution processable characteristics. This work is concluded with several synthetic routes to overcome the current limitations of our first generation of cruciform coordination polymers and cyclic peptide structures.
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28

Coltart, Donald M. "Synthetic studies on angiotensin-converting enzyme inhibitors, pyridines, and peptides". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0014/NQ59572.pdf.

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29

Mason, Richard J. Jr. "A novel and efficient synthesis of imidazo[1,5-a]Pyridines". DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 2007. http://digitalcommons.auctr.edu/dissertations/2361.

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A one-pot and straightforward synthesis, which results in the formation of imidazo[l,5-a]pyridines, has been intensely investigated. This methodology has been applied to 2,2'-pyridil, a- pyridoin and 2-benzoylpyridne ketone systems respectively.Treatment of 2,2'-pyridiI, a -pyridoin or 2-benzoylpyridine with aromatic aldehydes, and ammonium acetate in the presence of hot acetic acid has been shown to give l-(2-Pyridoyl)-3-phenylimidazolesand l,3-di-phenylimidazo[l,5-a]pyridines in good to excellent yields. These reactions were carried out without the use of metal catalysts, which is a commonly used methodology for imidazo[l,5-a]pyridine synthesis. A new and efficient synthesis of l,3-diaryl-[l,5-a]imidazopyridines has also been developed based on the reaction of 2-benzoylpyiridne with aldehydes in the presence of ammonium acetate and hot acetic acid Aldehydes applicable to this reaction include aryl aldehydes, heteroaromatic aldehydes, salicylaldehydes.
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30

Banting, L. "Synthesis and evaluation of perhydroimidazolo[3,4-a]pyridines as fungicides". Thesis, University of Portsmouth, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355127.

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31

Abou-Shehada, Sarah. "Lewis acids for the activation of pyridines for further functionalisation". Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655724.

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This thesis outlines work carried out over the past three years concerning the development of an experimentally simple, sustainable catalytic method for the functionalisation of pyridines by means of a zinc nitrate based Lewis acid. It encompasses reaction discovery and optimisation, determination of the scope of the method through nucleophile and substrate screens as well as investigations into the mechanism by which the reaction takes place. Chapter 1 gives a general overview of the industrial relevance of pyridine functionalisation as well as the synthetic methods for the synthesis of ring functionalised pyridines, covering traditional stoichiometric aromatic substitution methods, transition metal catalysed cyclisations, standard catalytic methods for the functionalisation of pyridines: Buchwald-Hartwig and Ulmann reactions, as well as a précis of some recent transition metal catalysed methods for C-H functionalisation of pyridines. It also reviews classical and transition metal catalysed methods for conjugate addition and Diels–Alder reactions of vinylpyridines. Chapter 2 involves reaction discovery for the use of Lewis acids for the activation of pyridines towards nucleophilic aromatic substitutions, reaction optimisations, kinetic investigations and an examination of the scope in substrates and incoming groups. Chapter 3 investigates the use of Lewis acids for the activation of vinylpyridines toward conjugate addition, reaction optimisations, investigations into scope of incoming groups and subsequent optimisation studies for each. The method is also extended to Diels–Alder cyclisations, for which the reaction is also optimised.
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32

Trécourt, François. "Elaboration de dérivés carbonylés orthosubstitués de la pyridine : application d'une nouvelle méthode de synthèse de pyridines, synthèse d'hétérocycles du type coumarine et xanthone". Rouen, 1987. http://www.theses.fr/1987ROUES021.

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A partir de bromo-3 pyridines orthosubstituées par un fluor, un chlore, un méthoxy, un méthylthio, une première méthode de synthèse a permis d'élaborer des dérivés carbonylés (aldéhydes, cétones) orthosubstitués de la pyridine en utilisant la réaction d'échange halogène-métal. Cette méthode donne de bons résultats mais comporte en général un nombre important d'étapes. Une deuxième méthode de synthèse des dérivés carbonylés orthosubstitués de la pyridine a été mise en oeuvre. Cette méthode, basée sur la réaction de métallation régiosélective de dérivés monosubstitués de la pyridine (fluoro, chloro, méthoxy pyridines) est facile a mettre en oeuvre et permet d'accéder en une ou deux étapes à des formylpyridines , des pyridyléthanones et des pyridylméthanones orthosubstituées. Les dérivés carbonylés ainsi préparés nous ont permis de synthétiser des polyhétérocycles comportant au moins un cycle pyridinique : azacoumarines, azathiocoumarines, azaxanthones, diazathioxanthones. Lors de ces synthèses, le chlorure de pyridinium s'est révélé être un excellent agent de cyclisation
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33

Trecourt, François. "Elaboration de dérivés carbonyles orthosubstitués de la pyridine application d'une nouvelle méthode de synthèse de pyridines, synthèse d'hétérocycles du type coumarine et xanthone /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37610334q.

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34

Shawcross, Andrew Paul. "The synthesis of novel heterocyclic compounds and observations on the Vilsmeier reaction". Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328112.

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35

Lee, Chien-Ming. "Hydrogen-bonded main-chain liquid crystalline association polymers". Thesis, University of Cambridge, 1994. https://www.repository.cam.ac.uk/handle/1810/272680.

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36

Chen, Quan Verfasser], e Paul [Akademischer Betreuer] [Knochel. "BF3-mediated direct functionalizations of pyridines / Quan Chen. Betreuer: Paul Knochel". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1060318563/34.

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37

Stapleton, David Robert. "Photolytic and photocatalytic (Ti02) destruction of halogenated pyridines in aqueous solution". Thesis, University of Leeds, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.485194.

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The effects of direct photolysis and combined photolysis/photocatalysis (254 nm) on the removal of the 2-halogenated pyridines, 3-chloropyridine, 2 & 3-hydroxypyridine and pyridine were investigated in aqueous solution (400 ml, 2.64 mMol L-1 , 293-323 K). Complete removal of all substrates and primary products was observed under all conditions studied, aside from a. photostable. product formed in the photolysis of 2-IPY. The degradation of the halogenated pyridines showed a strong temperature dependence. The order of rate of degradation was found to be: 2-FPY > 2-BPY > 2-CPY > 2-IPY >3-CPY The differences in the rates of reaction between the halogenated pyridines are attributed to UV absorbance (and quantum yield), electronegativity of halogen, mechanism of reaction and .'t. structure of primary product. The effects of dissolved oxygen, pH, agitation (swirl-flow) and tertbutanol were examined. None of these parameters had a significant effect on the degradation ofthe substrate. For 2-chloropyridine (2~CPY), 2-bromopyridine (2-BPY) and 2-iodopyridine (2-IPY), 2- hydroxypyridine (2-HPY) was identified as the primary product. Similarly, 3-hydroxypyridine (3- HPY) was identified in the degradation of 3-chloropyridine (3-CPY), however to a lesser extent. The formation and destruction of 2-HPY was measured under a variety experimental conditions and mathematical simulation was conducted [Levenspiel 1999]. All results were compared with the degradation of 2-HPY as the initial substrate. All variables studied had a significant effect on the degradation of 2-HPY. The degradation rates of 2-HPY and 3-HPY were considerably lower than the respective halogenated pyridines (5-10 times longer). This is attributed to lower UV absorbance and the absence of the photohydrolysis reaction observed in the case of the halogenated pyridines. In all cases the degradation of the substrate molecule was found to fit pseudo first order rate kinetics. The corresponding activation energy calculations were performed for each ofthese halogenated substrates. Experiments were performed using supported Ti02~ prepared by ... the coating methods published by Gelover et aI, 2004 and Yun et aI, 2004. No. significant effect was observed in the . . degradation rates measured compared with direct photolysis alone. A slurry combined photolytic/photocatalytic system was employed using powder catalyst, Degussa P-25. Light blocking effects (i.e. suppression of direct photolysis through solution turbidity) were found to be more prominent than the photocatalytic effects in the degradation of 2-CPY. Changes in pH and catalyst concentration, as well as the use of tert-butanol (as an OHo radical scavenge) had a significant impact of the degradation profiles of the substrate and/or primary intermediate. The primary photocatalytic degradation mechanism of the substrate was found to be electron transfer and the greater susceptibility of2-fluoropyridine (2-FPY) to photocatalysis as opposed to 2-CPY is attributed to displacement of hydroxyl radicals from the catalyst surface by F [Minero et aI, 2000a]. Kinetic analysis of the combined photolytic/photocatalytic system showed'that at low catalyst concentrations «0.05 g L·1 ), a non-linear relationship between catalyst concentration and the contribution of photocatalysis to the overall degradation rate exists. At higher catalyst concentrations, this relationship becomes linear, indicating a shift from the light blocking of direct photolysis to a fall in the photocatalytic degradation efficiency due to the inability of the light to penetrate the solution. Arange ofphotolytic and photocatalytic degradation products were identified using 2-FPY, 2-CPY and 3-CPY as the substrates. 2-HPY was not formed in sigIl:ificant quantities in the direct photolysis of2-FPY. It is believed that a one step reaction occurs to form the primary degradation product of 2-HPY. Chlorination, ring opening, ring contraction and photooxidation reactions were also observed. In the case of 3-CPY, several photodimer reactions were also identified. In the photodegradation or' 2-IPY, a stable product was observed, 'believed to be formed through the excitation of the liberated iodine ion. The photocatalytic degradation pathway of 2-FPY and 2CPY were found t~ differ. This was attributed to C-Halogen bond scission, which is postulated to OCcur in the case of2-FPY, but not 2-CPY. TOC removal was 'observed In hath·· photolytic and photocatalytic experiments. In the photolytic case, extended periods oftime was required to achieve this (around 900 minutes). In the case of aerated photolytic experiments, it is. believed that stripping (i.e. loss of VOCs through evaporation) was largely responsible for an observed increase in TOC reduction. The addition· of Ti02 (0.02-1 g Lot) had no significaf;lt effect on TOe removal rates. This was again attributed to stripping effects. It was also found that the TOC reduction of 2-HPY (when taken as the initial substrate) was significantly slower than 2-CPY, despite 2-HPY being the primary degradation product of2-CPY.
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38

Zadykowicz, Jerzy. "Bis(pyrazolyl)pyridines and their mono- and binuclear Ru(II) complexes". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ33555.pdf.

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39

Chapaneri, Krishna. "One-pot methodology for the synthesis of polysubstituted pyridines and terpyridines". Thesis, Cardiff University, 2008. http://orca.cf.ac.uk/54830/.

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Polysubstituted pyridines are prepared by a one-pot three-component cyclocondensation process, developed by modification and improvement of the traditional Bohlmann-Rahtz reaction. The synthesis combines a 1,3-dicarbonyl compound, ammonia, and an alkynone without the use of an additional acid catalyst. This three-component heteroannulation reaction proceeds by tandem Michael addition-heterocyclization with total control of regiochemistry and the resulting library of pyridines is isolated in good yield. Modified Bohlmann-Rahtz procedures were applied to the synthesis of a range of terpyridines, by a two- and three-component condensation of 2,6-propynoylpyridine derivatives and a range of enamines, or 1,3-dicarbonyl compounds and ammonia, proceeding in moderate to good yield using a range of conditions. The synthesis of fluorescent cyanopyridines with desirable photophysical properties from p- aminocrotononitrile and a variety of heterocyclic alkynones was established by one-pot Bohlmann-Rahtz reaction in excellent yields. These cyanopyridines can be generated in good yield, rapidly, using microwave irradiation. Primary thioamides are prepared in excellent yield from the corresponding nitriles by treatment with ammonium sulfide in methanol, at room temperature for electron deficient aromatic nitriles or under microwave irradiation at 80 C or 130 C in 15-30 minutes for other aromatic and aliphatic nitriles without the need for chromatographic purification.
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40

Trethewey, A. N. "Synthesis and evaluation of perhydro-oxazolo [3,4-a] pyridines as fungicides". Thesis, University of Portsmouth, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.354382.

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41

Hamzik, Philip J. (Philip Jonathan). "Synthesis of pyridines via [4 + 2] cycloadditions of vinylallenes with azadienophiles". Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101546.

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Abstract (sommario):
Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemistry, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references.
Pyridines are an important class of heterocycle with widespread applications. However, the efficient preparation of substituted pyridines remains a challenge in organic synthesis. This thesis describes new annulation strategies for the synthesis of highly substituted pyridines that involve [4 + 2] cycloadditions of vinylallenes with azadienophiles. Part II of this thesis describes a unimolecular, formal [2 + 2 + 2] cycloaddition strategy for the synthesis of tricyclic pyridines based on intramolecular propargylic ene/imino Diels-Alder reaction cascades. In this variant, unactivated oximino ethers and NN-dialkylhydrazones function as dienophiles in thermal Diels-Alder reactions. Part III of this thesis describes strategies for the synthesis of bicyclic and monocyclic 2-sulfonylpyrdines based on [4 + 2] cycloadditions of vinylallenes with tosyl cyanide. In addition, Part III discusses the synthetic elaboration of these 2- sulfonylpyridines via nucleophilic aromatic substitution reactions. Overall, annulation strategies based on [4 + 2] cycloadditions of vinylallenes with azadienophiles have been developed for the preparation of highly substituted pyridines in an efficient, convergent, and regioselective fashion.
by Philip J. Hamzik.
Ph. D.
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42

Henney, Roland Patrick Graham. "The transition metal chemistry of some thienyl- and phenyl-substituted pyridines". Thesis, University of Cambridge, 1991. https://www.repository.cam.ac.uk/handle/1810/271903.

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43

Monmoton, Sophie. "Polyélectrolytes linéaires et hyperramifiés par poly(N-alkylation) de pyridines substituées". Paris 6, 2007. http://www.theses.fr/2007PA066163.

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Ce travail est consacré à la synthèse et à la caractérisation de nouveaux polyélectrolytes de type polypyridiniums linéaires et hyperramifiés, ces derniers pouvant ouvrir la voie à la préparation de « micelles monomoléculaires ». La synthèse des polymères a été réalisée par poly(N-alkylation) de pyridines substituées. Les polymères linéaires sont obtenus à partir de deux monomères commerciaux de type AB : la 3-bromométhylpyridine hydrobromée et la 4-bromométhylpyridine hydrobromée. La modification de leur contre-ion permet de moduler leurs propriétés thermiques et leurs solubilités. De nouveaux polymères hyperramifiés ont été obtenus à partir de monomères AB2 synthétisés : la 3,5-di(bromométhyl)pyridine hydrobromée et la 3,5-di(bromobutyl)pyridine hydrobromée. Leurs propriétés thermiques et leurs solubilités ont été évaluées. Enfin, une étude cinétique a permis d’établir un modèle cinétique et les différentes étapes de polymérisation. La différence de réactivité des monomères a été mise en évidence par la détermination des constantes de vitesse et des énergies d’activation.
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44

Malicorne, Gilles. "Thiéno (2,3-b) et (3,2-b) pyridines : synthèse et activité antibactérienne". Montpellier 2, 1987. http://www.theses.fr/1987MON20277.

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45

Doise, Muriel. "Synthèse d'oxazolo et d'imidazo(m, n-x)pyridines, pyrimidines et pyrazines". Lille 1, 1991. http://www.theses.fr/1991LIL10129.

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Ce travail décrit la synthèse et l'étude structurale de nouveaux composés hétérocycliques condensés dérivés d'orthohydroxyaminoazines. La première partie est consacrée à la synthèse de deux nouveaux hétérocycles fondamentaux isostères de la purine: l'oxazolo(4,5-b)pyridine et de l'oxazolo(4,5-d) pyrimidine ainsi que celle de leurs dérivés substitués en -2; cette seconde série était jusqu'alors inconnue. La seconde partie décrit la synthèse de nouveaux phénols susceptibles de présenter des propriétés complexantes en série imidazo(1,2-a)pyridine et pyrazine par condensation de glyoxals avec la benzyloxy-3 amino-2 pyridine ou la méthoxy-3 amino-2 pyrazine. Après clivage de la fonction éther on aboutit aux dihydroxy-3,8 méthyl-2 (ou phényl-2) imidazo(1,2-a)pyridines et pyrazines. L'étude spectroscopique en IR, UV et RMN montre l'existence de tautomères zwitterioniques et, dans la seconde série, de formes oxo. La troisième partie est consacrée à l'ouverture en milieu HClO4/MeOH d'hydroxy-3 imidazo(1,2-a)pyridines, ou à l'action de ce même milieu sur un mélange de glyoxals et d'amino-2 pyridines diversement substitués, qui conduisent à des N-(pyridyl-2) amino-2 esters et acides dérivés de la glycine, de l'alanine et de la phénylalanine dans lesquels le cycle pyridine est substitué par un groupe 3-OH, 3-NO2 ou 5-NO2. Tous les composés étudiés ont été caractérisés par étude spectroscopique en IR, UV et RMN (1H et 13C) ainsi que par spectrométrie de masse
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46

Chen, Quan [Verfasser], e Paul [Akademischer Betreuer] Knochel. "BF3-mediated direct functionalizations of pyridines / Quan Chen. Betreuer: Paul Knochel". München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1060318563/34.

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47

Pitman, Mark A. "The synthesis and reactivity of substituted (1,2,3)-triazolo[1,5-a] pyridines". Thesis, Keele University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317599.

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48

Malicorne, Gilles. "Thiéno (2,3-b) et (3,2-b) pyridines synthèse et activité antibactérienne /". Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb376075729.

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49

Oudot, Romain. "Synthèse de dérivés imidazo[1,2-a] pyridines et imidazo[1,2-b] pyridazines tricycliques". Thesis, Tours, 2009. http://www.theses.fr/2009TOUR3804.

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Abstract (sommario):
Les motifs imidazo[1,2-a]pyridines et imidazo[1,2-b]pyridazines sont des noyaux très étudiés par la communauté scientifique, notamment dans le domaine thérapeutique. Ceci s’explique en partie par les progrès récents réalisés dans le domaine de la métallocatalyse qui ont permis une fonctionnalisation plus simple de ces molécules. Cependant, les dérivés tricycliques de ces structures sont restés assez peu étudiés malgré le fait que certains de leurs isostères présentent des propriétés biologiques intéressantes. Les travaux de cette thèse ont porté sur deux projets distincts : -La synthèse d’imidazo[1,2-b]pyridazines présentant un troisième cycle diazoté entre les positions 7 et 8, dans le cadre d’un contrat conclu avec la société Sanofi-Aventis. Ces composés, totalement originaux, représentent un véritable défi chimique et leur synthèse a nécessité d’importants travaux de mise au point. Nous avons ainsi employé différentes méthodes de couplages métallocatalysés. -La synthèse d’imidazo[1,2-a]pyridines un troisième cycle pyridinique entre les positions 2 et 3. Ces molécules, peu décrites dans la littérature, n’ont fait l’objet d’aucune évaluation biologique. Dans le but de synthétiser efficacement une chimiothèque intéressante pour ces structures, j’ai développé une méthode d’hétérocyclisation qui nous permet d’obtenir en deux étapes, gràce à des produits de départ très accessible, une importante variété de tricycles
The imidazo[1,2-a]pyridines and imidazo[1,2-b]pyridazines moeities are very studied by scientific community, specially in therapeutic field. This is mostly due to recent progress in metallocatalyzed couplings which allow easier functionnalization of these structures. However, the tricyclic derivatives of these compounds remained not very studied despite important biological properties of some of there isosters. This thesis is divided in two parts : -The synthesis of imidazo[1,2-b]pyridazines with a dinitrogenated third cycle between the positions 7 and 8 in collaboration with Sanofi-Aventis. These new compounds were a real chemical challenge and their synthesis required important works of development. We used various metallocatalyzed couplings methods. -The synthesis of imidazo[1,2-a]pyridines with a pyridinic cycle between the positions 2 and 3. These molecules, poorly described in the literature, have never been subject to biological study. In order to effectively synthesize an interesting range of these structures, I have developed a new heterocyclization method which allows us to obtain in two steps, starting from commercialy available starting materials, some original tricyclics compounds
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50

Roche, Mélanie. "Stratégies innovantes pour le radiomarquage de macro-biomolécules au fluor-18 pour des applications en imagerie moléculaire in vivo". Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS031/document.

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Le radiomarquage des macro-biomolécules au fluor-18 représente un défi majeur en radiochimie vu leur importance en imagerie moléculaire. Les macro-biomolécules et en particulier les peptides offrent une diversité moléculaire et un ciblage in vivo souvent plus spécifiques et sélectifs que les molécules de plus faibles poids moléculaires. Cependant, les conditions standards de radiomarquage au fluor-18 seraient destructrices pour de tels composés et ne peuvent être utilisées directement. Peu de méthodes directes de radiomarquage existent et présentent certains inconvénients (température encore élevée, activité molaire faible, méthodes peu versatiles…). C’est pourquoi, le radiomarquage par approche prosthétique en deux étapes reste une méthode de choix. Cette stratégie séquentielle implique tout d’abord la préparation d’une molécule radiofluorée, appelée groupe prosthétique, puis sa conjugaison à la macro-biomolécule dans des conditions chimiques biocompatibles. L’objectif de ce travail de thèse a consisté à développer de nouvelles méthodes générales de radiomarquage de macro-biomolécules visant in fine des applications de radiomarquage direct in vivo. Les enjeux principaux ont été la diminution du temps de marquage pour améliorer les procédés de radiosynthèse compte tenu de la demi-vie du fluor-18 (109,8 min), le besoin d’automatisation ainsi que la vitesse et la bioorthogonalité des réactions de conjugaison pour des applications en milieu complexe et dilué. Tout d’abord, l’étude de trois réactions de chimie click, CuAAC, SPAAC et SPSAC, de vitesse et de biocompatibilité croissantes a été considérée. Le développement de groupes prosthétiques spécifiques de chacune d’entre elles ainsi que leur conjugaison sur des composés modèles ont ensuite été étudiés. Par la suite, une étude méthodologique sur la radiofluoration de pyridines substituées a été initiée afin d’obtenir des entités radiomarquables dans des conditions suffisamment douces permettant la « pré-conjuguaison » à la macro-biomolécule avant l’étape de radiofluoration. Enfin, l’utilisation d’un étiquetage enzymatique, le SNAP-tag, a également été explorée et un substrat radiofluoré spécifique synthétisé. Ces différentes approches ont permis d’élargir le panel des méthodes permettant un radiomarquage efficace et biocompatible de macro-biomolécules
Fluorine-18 radiolabeling of biologics is a challenge in radiochemistry due to their increasing interest in molecular imaging. Biologics, and particularly peptides, offer molecular diversity and often higher specific and selective in vivo targeting compared to low molecular weight molecules. However, fluorine-18-radiolabeling standard conditions could not be used directly because biologics would suffer from these drastic conditions. Only a few direct radiolabeling methods are available and present some drawbacks (high temperature, low molar activity, lack of versatility…). Therefore, a two-steps prosthetic radiolabeling approach remains the method of choice. This sequential strategy involves the preparation of a fluorine-18-labeled molecule, called prosthetic group, which is then conjugated with the macromolecule in biocompatible chemical conditions. The aim of this PhD work was to develop new general methods for the radiolabeling of biologics directed toward in vivo radiolabeling applications. Major issues were time and radiosynthesis processes with regard to the fluorine-18 half life, automatization as well as constant rate and bioorthogonality of conjugation reactions for applications in complex and diluted environment.The first part is devoted to the study of three click chemistry reactions, CuAAC, SPAAC and SPSAC leading to enhanced reaction rates and biocompatibility. Specific prosthetic groups were developed for each reaction and their conjugation was studied with model compounds. Furthermore, a methodological study involving the radiofluorination of substituted pyridines was initiated for the production of entities for mild radiolabeling conditions compatible with a “pre-conjugation” to the biologics before radiofluorination. Finally, an enzymatic labeling approach using the SNAP-tag self-labeling enzyme was explored and a specific radiofluorinated substrate was synthesized. These different approaches allowed an extent of the panel of methods for effective and biocompatible radiolabeling of biologics
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