• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 1
  • Tagged with
  • 4
  • 4
  • 4
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Studies towards the decarboxylative cross-coupling of azole-4-carboxylic acids

Stephen, Jennifer Lea January 2015 (has links)
Some interesting, biologically active natural products have been found to contain poly-azole fragments within their core. These fragments are linked through the 2- position of one azole and the 4-position of its neighbour. Decarboxylative cross-coupling methodology may provide a route to these desired linked azoles through cross-coupling of azole-4-carboxylic acids with azole-2- halides or with azoles containing no substitution at the 2-position. Investigations into the silver-mediated decarboxylation, and subsequent coupling potential, of thiazole and oxazole-4-carboxylic acids are reported. Methods towards the synthesis of novel chlorinated thiazole and oxazole acids and their precursors are also described. A method to successfully couple these acids to aryl iodides has been developed and the scope of this reaction extended to a variety of functionalised azole-4-carboxylic acids. Attempts to extend this methodology and combine the decarboxylative coupling with CH activation of a second azole are also described.
2

Vers la synthèse totale des amphidinolides C et F, des macrocycles d’origine marine prometteurs pour la thérapie anticancéreuse / Toward total synthesis of amphidinolides C and F, promising marine macrocycles for anticancer therapy

Fenneteau, Johan 12 January 2015 (has links)
Les amphidinolides C et F sont des macrocycles isolés de dinoflagellés Amphidinium sp. vivant en symbiose avec des plathelminthes Amphiscolops sp.. Ces amphidinolides ont montrés des activités cytotoxiques importantes sur des lignées de cellules KB et L1210. Au vu du potentiel thérapeutique intéressant et de l’architecture complexe de ces substances naturelles, un programme de synthèse totale a été initié. Dans ce manuscrit, différentes approches pour la construction de ces produits naturels sont détaillées, les principaux défis étant la création efficace de motifs 2,5-Trans THF, l’incorporation de motifs diénique par des méthodes catalytiques et le contrôle des centres asymétriques grâce à des époxydes chiraux. / Amphidinolides C and F are macrocyles isolated from dinoflagellates Amphidinium sp., which are living in symbiosis with marine flatworms Amphiscolops sp.. Those amphidinolides had shown an important cytotoxic activity against KB and L1210 cell lines. Due to promising therapeutical potential and complex framework of these natural products, a total synthesis program had been initiated. In this manuscript, different approaches for the construction of these natural targets are detailed. The main challenges were the efficient formation of 2,5-Trans THF, incorporation of dienic moieties by catalytic processes and the installation of chiral centers through chiral epoxyde chemistry.
3

Synthèse par cycloaddition 1,3-dipolaire d’hétérocycles et spiro-hétérocycles glycosylés comme inhibiteurs de la glycogène phosphorylase et agents anti-hyperglycémiants : évaluation et tests biologiques / 1,3-Dipolar cycloaddition synthesis of glycosylated heterocycles and spiro-heterocycles as glycogen phosphorylase inhibitors : biological testing and evaluation

Goyard, David 15 December 2011 (has links)
A la suite des nombreux travaux sur l’inhibition de la glycogène phosphorylase (GP) menés au laboratoire et au travers de diverses collaborations, cette thèse décrit en cinq chapitres suivis d’une partie expérimentale détaillée, les dernières avancées en termes de synthèse et d’évaluation biologique des inhibiteurs du site catalytique de la GP. La chapitre I de ce manuscrit est consacrée à la présentation des diabètes et plus particulièrement du diabète de type II dont le traitement, motivation première de ce projet, repose sur la connaissance des mécanismes complexes régulant la glycémie. Les différents inhibiteurs synthétisés sont classés par famille selon leur structure qui associe un aglycone hétérocyclique, susceptible d’affinité pour le canal β proche du site actif de l’enzyme, avec un motif glycopyranosidique, ou glycopyranosylidène dans le cas des motifs spiro. Le chapitre II est consacré aux inhibiteurs spiro-bicycliques tels que les glucopyranosylidène-spiro-1,4,2-oxathiazoles et les glucopyranosylidène-spiro-isoxazolines. Le chapitre III décrit la synthèse de C- et N-glycosyles hétérocycles, principalement des glycopyranosyl-1,2,3-triazoles. Enfin le chapitre IV décrit la fonctionnalisation de 5-halogéno-1,2,3-triazoles 4-substitués par couplages pallado-catalysés qui ont constitué un développement imprévu mais original des travaux. Pour terminer, le chapitre V décrit l’évaluation des molécules préparées en tant qu’inhibiteurs de la glycogène phosphorylase. Les expériences et résultats d’enzymologie, de cristallographie ainsi que les tests cellulaires in vitro et in vivo sur le rat sont présentés / Following many studies lead on the inhibition of glycogen phosphorylase (GP) in our laboratory an trough several collaborations, this thesis describes in five chapters and a detailed experimental section, the most recent advances in the areas of synthesis and biological evaluation of GP’s catalytic site inhibitors. Chapter I is dedicated to the description of diabetes and especially type 2 diabetes of which treatment, the main goal of this project, requires knowledge of the complex mechanisms that regulates glycemia. Synthesized inhibitors are broken down into families according to their structure which associates an heterocyclic aglycon, prone to binding in the β pocket lining the active site, with a glycopyranoside or glycopyranosylidene moiety in the case of spiro compounds. Chapter II focuses on spiro-bicyclic inhibitors such as glucopyranosilidene-spiro-1,4,2-oxathiazoles and glucopranosylidene-spiro-isoxazolines. Chapter III describes the synthesis of C- and N-glycosyl-heterocycles, mainly glycopyranosyl-1,2,3-triazoles. Finally, chapter IV studies the palladium-mediated cross coupling fonctionalization of 4-substituted-5-halogenated-1,2,3-triazoles that represents an unexpected but interesting development of the project. To conclude, chapter V gathers the evaluation of synthesized molecules as GP inhibitors. Enzymology and crystallography as well as in vitro and in vivo experiments are presented
4

(Metallo-)Dendrimers in Catalysis, Nanoparticle Stabilization and Biological Application / (Metallo-)Dendrimere in Katalyse, Nanopartikelstabilisierung und Biologischen Anwendungen

Dietrich, Sascha 06 January 2012 (has links)
(Metallo-)Dendrimers in Catalysis, Nanoparticle Stabilization and Biological Application Technische Universität Chemnitz, Fakultät für Naturwissenschaften Dissertation 2011, 165 Seiten Die vorliegende Dissertationsschrift befasst sich mit der Darstellung, Charakterisierung und Anwendung neuartiger (Metallo-)Dendrimere. Den Schwerpunkt der Arbeit bildet dabei die terminale Funktionalisierung (Poly)amidoamin-basierender Dendrimere kleiner Generationen. Durch Standardpeptid-Knüpfungsreaktionen von 1,1´-(Diphenylphosphino)ferrocen-carbonsäure an dendritische (Poly)amidoamine ist eine Serie entsprechend funktionalisierter Metallodendrimere zugänglich. Die metallorganischen, Dendrimer-immobilisierten Engruppen können durch Zugabe von [Pd(3-C3H5)Cl]2 in heterobimetallische Übergangsmetallkomplexe umgewandelt werden und finden Einsatz als katalytisch aktive Systeme in C,C-Kreuzkupplungsreaktionen nach Heck. Ein weiterer Gegenstand der Arbeit ist die terminale Modifikation von (dendritischen) Ami-nen mit (Sp)-2-(Diphenylphosphino)ferrocen-1-carbonsäure. Nach erfolgter Umsetzung mit [Pd(3-C3H5)Cl]2 werden die erhaltenen planar-chiralen Verbindungen als Katalysatoren in asymmetrischen allylischen Substitutionsreaktionen eingesetzt. Ferner ist die Darstellung (Oligo)ethylenglykolether-terminierter (Poly)amidoamin-Dendrimere beschrieben. Diese werden als Stabilisatoren zur in-situ Generierung von Gold- sowie Magnetit-Nanopartikeln eingesetzt. Der Einfluss der dendritischen Template auf die Kolloidgrößen und Morphologien sowie die Eigenschaften der gebildeten Hybridmaterialien werden aufgezeigt. Darüber hinaus befasst sich die Arbeit mit der Verwendung biokompatibler (Oligo)ethylenglykolether-Dendrimere als Wirkstoffträger für Zytostatika bei der Krebsthera-pie. Die im Rahmen von in vitro Untersuchungen erhaltenen Ergebnisse werden präsentiert.:Table of Contents Bibliografische Beschreibung und Referat ii Selbstständigkeitserklärung iii Table of Contents vii List of Abbreviations xi Präambel xvi A Introduction 1 1. Dendrimers 1 2. Nanomaterials 4 3. References 7 B State of Knowledge 12 1. Dendrimers 12 1.1. Synthesis and Characterization 12 1.2. Functional Dendrimers 15 2. Characterization Techniques for Dendrimer-Nanomaterial Assemblies 24 3. Motivation 26 4. References 27 C Amidoamine-based Dendrimers with End-grafted Pd-Fe Units: Synthesis, Characterization and Their Use in the Heck Reaction 34 1. Introduction 34 2. Results and Discussion 35 2.1. Synthesis of Amidoamine Dendrimers 35 2.2. Synthesis of Metallo- and Selenium-Phosphine Amidoamine Dendrimers 36 2.3. Catalysis with Heterobimetallic Iron-Palladium Amidoamine Dendrimers 39 3. Conclusions 41 4. Experimental 42 4.1. Materials and Methods 42 4.2. Preparation of 2 43 4.3. Preparation of 9-Fe 43 4.4. Preparation of 5-Fe-Pd 44 4.5. Preparation of 6-Fe-Pd 44 4.6. Preparation of 7-Fe-Pd 45 4.7. Preparation of 8-Fe-Pd 46 4.8. Preparation of 9-Fe-Pd 46 4.9. Preparation of 5-Fe-Se 47 4.10. Preparation of 9-Fe-Se 48 4.11. General Procedure for the Heck-Reaction 48 5. Acknowledgement 49 6. References 49 D A Preparation of Planar-Chiral Multidonor Phosphanyl-Ferrocene Carboxamides and Their Application as Ligands for Palladium-Catalyzed Asymmetric Allylic Alkylation 52 1. Introduction 52 2. Results and Discussion 53 2.1. Syntheses and Characterization 53 2.2. Solid-State Structure of (Sp)–2 55 2.3. Catalytic Tests 57 3. Conclusions 58 4. Experimental 59 4.1. Materials and Methods 59 4.2. Preparation of Simple Amides. A General Procedure 59 4.3. Preparation of 6 61 4.4. Preparation of (Sp,Sp)–4 61 4.5. Preparation of 7 62 4.6. Preparation of (Sp,Sp,Sp)–5 62 4.7. Asymmetric Allylic Alkylation. A General Procedure 63 4.8. X-ray Crystallography 63 5. Acknowledgements 64 6. References 64 E Au Nanoparticles Stabilized by PEGylated Low-Generation PAMAM Dendrimers: Design, Characterization and Properties 68 1. Introduction 68 2. Materials and Methods 69 2.1. Synthesis of Stabilizers 69 2.2. Preparation Procedure for Gold Nanoparticles 70 3. Results and Discussion 70 3.1. Dendritic Stabilizers 70 3.2. Dendritic Stabilized Gold Nanoparticles 72 3.3. Physical and Chemical Characterization 73 4. Conclusion 79 5. Acknowledgement 80 6. Supplementary Material 80 7. References 80 F Design, Characterization and Magnetic Properties of Fe3O4-Nanoparticle Arrays Coated with PEGylated-Dendrimers 86 1. Introduction 86 2. Materials and Methods 88 2.1. Materials and Instruments 88 2.2. Synthesis Procedure for Fe3O4 Nanoparticles 89 3. Results and Discussion 91 3.1. Preparation and Characterization of Dendrimer-Surfaced Fe3O4 Nanoparticles 91 3.2. Magnetic Characterization of Dendrimer-Coated Fe3O4 Nanoparticles 96 4. Conclusion 99 5. Acknowledgement 100 6. References 100 G Dendrimer - Doxorubicin Conjugate for Enhanced Therapeutic Effects for Cancer 103 1. Introduction 103 2. Experimental Section 105 2.1. Materials and Methods 105 2.2. Synthesis of OEGylated Poly(amidoamine) Dendrimer 2 106 2.3. Cell Viability Studies 107 2.4. Doxorubicin Loading and Release 107 2.5. In Vitro Cellular Uptake of Dendrimer-DOX Conjugate 109 3. Results and Discussion 109 3.1. Drug Loading and Release 109 3.2. Surface Potential of the Dendrimer-Drug Assembly 110 3.3. Structural Analysis of Dendrimer-DOX Conjugate 111 3.4. In Vitro DOX Release Profile from Dendrimer-Drug Conjugate 114 3.5. Cell Viability Studies of the Dendrimer-DOX Conjugate 117 3.6. Cellular Uptake by the Dendrimer-DOX Conjugate 118 3.7. Protein Adsorption Studies 119 4. Conclusions 119 5. Acknowledgements 120 6. Supplementary Material 120 7. References 121 H Summary 123 1. Summary 123 2. Zusammenfassung 129 Danksagung 136 I Appendix 137 1. Appendix Chapter C 137 2. Appendix Chapter D 139 3. Appendix Chapter E 140 4. Appendix Chapter F 142 5. Appendix Chapter G 144 Lebenslauf 145 Liste der Publikationen, Vorträge und Posterpräsentationen 147 Publikationen 147 Poster 148 Vorträge 149

Page generated in 0.0877 seconds