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  • 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.
91

ラジカル超原子価ヨウ素(III)試薬を用いた直接的C-H活性化反応の開発

臼井, 明日香 23 March 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18808号 / 理博第4066号 / 新制||理||1585(附属図書館) / 31759 / 京都大学大学院理学研究科化学専攻 / (主査)教授 丸岡 啓二, 教授 時任 宣博, 教授 大須賀 篤弘 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
92

Ecology of bacterioplankton specific to the oxygenated hypolimnia of deep freshwater lakes / 大水深淡水湖の有酸素深水層に特有な細菌の生態解明

Okazaki, Yusuke 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20953号 / 理博第4405号 / 新制||理||1633(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 中野 伸一, 教授 木庭 啓介, 教授 中川 尚史 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
93

Modular Surface Functionalization of Polyisobutylene-based Biomaterials

Alvarez Albarran, Alejandra 11 September 2014 (has links)
No description available.
94

Growth of Semiconductor and Semiconducting Oxides Nanowires by Vacuum Evaporation Methods

Rakesh Kumar, Rajaboina January 2013 (has links) (PDF)
Recently, there has been a growing interest in semiconductor and semiconducting oxide nanowires for applications in electronics, energy conversion, energy storage and optoelectronic devices such as field effect transistors, solar cells, Li- ion batteries, gas sensors, light emitting diodes, field emission displays etc. Semiconductor and semiconducting oxide nanowires have been synthesized widely by different vapor transport methods. However, conditions like high growth temperature, low vacuum, carrier gases for the growth of nanowires, limit the applicability of the processes for the growth of nanowires on a large scale for different applications. In this thesis work, studies have been made on the growth of semiconductor and semiconducting oxide nanowires at a relatively lower substrate temperature (< 500 °C), in a high vacuum (1× 10-5 mbar), without employing any carrier gas, by electron beam and resistive thermal evaporation processes. The morphology, microstructure, and composition of the nanowires have been investigated using analytical techniques such as SEM, EDX, XRD, XPS, and TEM. The optical properties of the films such as reflectance, transmittance in the UV-visible and near IR region were studied using a spectrophotometer. Germanium nanowires were grown at a relatively lower substrate temperature of 380-450 °C on Si substrates by electron beam evaporation (EBE) process using a Au-assisted Vapor-Liquid-Solid mechanism. High purity Ge was evaporated in a high vacuum of 1× 10-5 mbar, and gold catalyst coated substrates maintained at a temperature of 380-450 °C resulted in the growth of germanium nanowires via Au-catalyzed VLS growth. The influence of deposition parameters such as the growth temperature, Ge evaporation rate, growth duration, and gold catalyst layer thickness has been investigated. The structural, morphological and compositional studies have shown that the grown nanowires were single-crystalline in nature and free from impurities. The growth mechanism of Germanium nanowires by EBE has been discussed. Studies were also made on Silicon nanowire growth with Indium and Bismuth as catalysts by electron beam evaporation. For the first time, silicon nanowires were grown with alternative catalysts by the e-beam evaporation method. The use of alternative catalysts such as Indium and Bismuth results in the decrease of nanowire growth temperature compared to Au catalyzed Si nanowire growth. The doping of the silicon nanowires is possible with an alternative catalyst. The second part of the thesis concerns the growth of oxide semiconductors such as SnO2, Sn doped Indium oxide (ITO) nanowires by the electron beam evaporation method. For the first time, SnO2 nanowires were grown with a Au-assisted VLS mechanism by the electron beam evaporation method at a low substrate temperature of 450 °C. SEM, XRD, XPS, TEM, EDS studies on the grown nanowires showed that they were single crystalline in nature and free of impurities. The influence of deposition parameters such as the growth temperature, oxygen partial pressure, evaporation rate of Sn, and the growth duration has been investigated. Studies were also done on the application of SnO2 nanowire films for UV light detection. ITO nanowires were grown via a self-catalytic VLS growth mechanism by electron beam evaporation without the use of any catalyst at a low substrate temperature of 250-400 °C. The influence of deposition parameters such as the growth temperature, oxygen partial pressure, evaporation rate of ITO, and growth duration has been investigated. Preliminary studies have been done on the application of ITO nanowire films for transparent conducting coatings as well as for antireflection coatings. The final part of the work is on the Au-assisted and self catalytic growth of SnO2 and In2O3 nanowires on Si substrates by resistive thermal evaporation. For the first time, SnO2 nanowires were grown with a Au-assisted VLS mechanism by the resistive thermal evaporation method at a low substrate temperature of 450 °C. SEM, XRD, XPS, TEM, and EDS studies on the grown nanowires showed that they were single crystalline in nature and free of impurities. Studies were also made on the application of SnO2 nanowire films for methanol sensing. The self-catalytic growth of SnO2 and In2O3 nanowires were deposited in high vacuum (5×10-5 mbar) by thermal evaporation using a modified evaporation source and a substrate arrangement. With this arrangement, branched SnO2 and In2O3 nanowires were grown on a Si substrate. The influence of deposition parameters such as the applied current to the evaporation boat, and oxygen partial pressure has been investigated. The growth mechanism behind the formation of the branched nanowires as well as nanowires has been explained on the basis of a self-catalytic vapor-liquid-solid growth mechanism. The highlight of this thesis work is employing e-beam evaporation and resistive thermal evaporation methods for nanowire growth at low substrate temperatures of ~ 300-500 °C. The grown nanowires were tested for applications such as gas sensing, transparent conducting coatings, UV light detection and antireflection coating etc. The thesis is divided into nine chapters and each of its content is briefly described below. Chapter 1 In this chapter, a brief introduction is given on nanomaterials and their applications. This chapter also gives an overview of the different techniques and different growth mechanisms used for nanowires growth. A brief overview of the applications of semiconductors and semiconductor oxide nanowires synthesized is also presented. Chapter 2 Different experimental techniques employed for the growth of Si, Ge, SnO2, In2O3, ITO nanowires have been described in detail in this chapter. Further, the details of the different techniques employed for the characterization of the grown nanowires were also presented. Chapter 3 In this chapter, studies on the growth of Germanium nanowires by electron beam evaporation (EBE) are given. The influence of deposition parameters such as growth temperature, evaporation rate of germanium, growth duration, and catalyst layer thickness was investigated. The morphology, structure, and composition of the nanowires were investigated by XRD, SEM, and TEM. The VLS growth mechanism has been discussed for the formation of the germanium nanowires by EBE using Au as a catalyst. Chapter 4 This chapter discusses the growth of Si nanowires with Indium and Bismuth as an alternate to Au-catalyst by electron beam evaporation. The influence of deposition parameters such as growth temperature, Si evaporation rate, growth duration, and catalyst layer thickness has been investigated. The grown nanowires were characterized using XRD, SEM, TEM and HRTEM. The Silicon nanowires growth mechanism has been discussed. Chapter 5 This chapter discusses the Au-catalyzed VLS growth of SnO2 nanowires by the electron beam evaporation method as well as Antimony doped SnO2 nanowires by co-evaporation method at a low substrate temperature of 450 °C. The grown nanowires were characterized using XRD, SEM, TEM, STEM, Elemental mapping, HRTEM, and XPS. The effect of deposition parameters such as oxygen partial pressure, growth temperature, catalyst layer thickness, evaporation rate of Sn, and the growth duration of nanowires were investigated. The SnO2 nanowires growth mechanism has been explained. Preliminary studies were made on the possible use of pure SnO2 and doped SnO2 nanowire films for UV light detection. SnO2 nanowire growth on different substrates such as stainless steel foil (SS), carbon nanosheets films, and graphene oxide films were studied. SnO2 nanowire growth on different substrates, especially SS foil will be useful for Li-ion battery applications. Chapter 6 This chapter discusses the self catalyzed VLS growth of Sn doped Indium oxide (ITO) nanowires by the electron beam evaporation method at a low temperature of 250-400 °C. The grown nanowires were characterized using XRD, SEM, TEM, STEM, HRTEM, and XPS. The effect of deposition parameters such as oxygen partial pressure, growth temperature, evaporation rate of ITO, and the growth duration of the nanowires were investigated. Preliminary studies were also made on the possible use of self-catalyzed ITO nanowire films for transparent conducting oxides and antireflection coatings. ITO nanowire growth on different and large area substrates such as stainless steel foil (SS), and Glass was done successfully. ITO nanowire growth on different substrates, especially large area glass substrates will be useful for optoelectronic devices. Chapter 7 In this chapter, studies on the growth of SnO2 nanowires by a cost-effective resistive thermal evaporation method at a relatively lower substrate temperature of 450 °C are presented. The grown nanowires were characterized using XRD, SEM, TEM, HRTEM, and XPS. Preliminary studies were done on the possible use of SnO2 nanowire films for methanol sensing. Chapter 8 This chapter discusses the self-catalytic growth of SnO2 and In2O3 nanowires by resistive thermal evaporation. The nanowires of SnO2 and In2O3 were grown at low temperatures by resistive thermal evaporation using a modified source and substrate arrangement. In this arrangement, branched SnO2 nanowires, and In2O3 nanowires growth was observed. The grown nanowires were characterized using XRD, SEM, TEM, HRTEM, and XPS. The possible growth mechanism for branched nanowires growth has been explained. Chapter 9 The significant results obtained in the present thesis work have been summarized in this chapter.
95

Studies of Platinum Polyynyl Complexes: Elaboration of Novel "Click" Cycloadducts and Fluorous and Polygon Based Platinum Polyyndiyl Systems

Clough, Melissa Catherine 1985- 14 March 2013 (has links)
The major directions of this dissertation involve (1) the syntheses and characterization of molecular polygons incorporating sp1hybridized carbon linkers and L2Pt corners (L2 = cis-1,3-diphosphine), (2) the development of protected carbon chain complexes featuring fluorous phosphine ligands and (3) click reactions of metal terminal polyynyl complexes and further metallations of the resulting triazole rings. A brief overview is provided in Chapter I. Chapter II details the syntheses of molecular squares containing bidendate diphosphine ligands of the formula R2C(CH2PPh2)2 where R = Me, Et, n-Bu, n-Dec, Bn, and p-tolCH2 (general designation dppp*), in which the R2 groups are intended to circumvent the solubility issues encountered by others. Their syntheses involve double substitutions of the dimesylate compounds R2C(CH2OMs)2 using KPPh2. Building blocks of the formulae (dppp*)PtCl2 and (dppp*)Pt((C≡C)2H)2 are synthesized and characterized, including one crystal structure of the latter. The target complexes are accessed by reactions of (dppp*)PtCl2 with (dppp*)Pt((C≡C)2H)2 under Sonogashira type conditions. Six new squares of the formula [(R2C(CH2PPh2)2)Pt(C≡C)2]4 are characterized including two crystal structures. Further topics include approaches to higher homologues and cyclocarbon synthesis. Chapter III focuses on carbon chain complexes bearing fluorous phosphine ligands of the formula P((CH2)mRfn)3 (Rfn = (CF2)n-1CF3; m/n = 2/8, 3/8, and 3/10). Precursors of the formula trans-(C6F5)((Rfn(CH2)m)3P)2PtCl are synthesized and characterized, including one crystal structure, which reveals phase separation of the fluorous and non-fluorous domains. Reactions with butadiyne give trans-(C6F5)((Rfn(CH2)m)3P)2Pt(C≡C)2H. Oxidative homocouplings afford the target complexes trans,trans-(C6F5)((Rfn(CH2)m)3P)2Pt(C≡C)4(C6F5)(P((CH2)mRfn)3)2Pt. Cyclic voltammetry indicates irreversible oxidations of the title compounds, in contrast to partially reversible oxidations of non-fluorous analogues. Chapter IV focuses on multimetallic complexes achieved by click reactions in metal coordination spheres. The copper catalyzed click reaction between trans-(C6F5)(p-tol3P)2Pt(C≡C)2H (1) and (η5-C5H4N3)Re(CO)3 affords the bimetallic 1,2,3-triazole trans-C6F5)(p1tol3P)2PtC≡CC=CHN((η51C5H4)Re(CO)3)N=N. Further reactions with Re(CO)5OTf and Re(CO)5Br give trimetallated adducts, which represent the first species of this type. An alternative route to a trimetallic complex involves the twofold cycloaddition of the diazide (η5-C5H4N3)2Fe and 1, giving (η5-C5H4NN=N-C(trans-(C≡C)Pt(Pp-tol3)2(C6F5)=CH)2Fe. The crystal structures of the di and trimetallic complexes are compared, but attempts to achieve a fourth metallation involving the =CH groups are unsuccessful. However, when the triazolium salt [trans-(C6F5)(p-tol3P)2PtC≡CC=CHN(CH2C6H5)N=N(Me)]+ I– is treated with Ag2O and [Rh(COD)Cl]2, a =CRh adduct is obtained. The success of =CH metallation is correlated to the 1H NMR chemical shift, indicative of an electronic effect.
96

Distorted arenes by Scholl cyclizations, towards twisted carbon nanoribbons / Synthèse de composés aromatiques polycycliques distordus par réaction de Scholl vers des nanorubans de carbone courbés

Pradhan, Anirban 23 September 2013 (has links)
Les nanorubans de carbone présentent aujourd’hui un grand intérêt en tant que segments de graphène aux propriétés électroniques modulables. Alors que des techniques de synthèse destructives top down donnent des rubans de très grande taille, d’autres techniques constructives bottom up, par synthèse organique, pourraient former des nanorubans bien définis de géométries contrôlées. Dans cette optique, la réaction de Scholl est un outil chimique précieux car elle permet la graphénisation de longs précurseurs flexibles de type polyphénylène.Etonnamment, des structures distordues peuvent être obtenues majoritairement même si des isomères plans moins encombrés sont a priori favorisés. Nous avons ainsi montré que contre toute attente même un encombrement stérique important n’a aucun effet notoire sur la régiosélectivité et que des composés aromatiques polycycliques courbés sont préférentiellement formés. Ainsi, des structures particulièrement tordues, tel que l’hexabenzotriphénylène (HBTP) peuvent être facilement obtenues à partir de précurseurs de type polyphénylène.Après avoir découvert cette régiosélectivité inattendue, nous en avons tiré parti pour former des composés de type polyhélicène. Plusieurs tentatives de formation de l’hexaphénanthrotriphénylène (HPTP) furent infructueuses à cause de problèmes de réactivité lors des synthèses des précurseurs flexibles correspondants. En mettant au point une stratégie de synthèse versatile fondée sur un précurseur commun, plusieurs substrats flexibles de symétrie C3 ont été synthétisés puis soumis à la réaction de Scholl. Des produits de réarrangement ont cependant été obtenus au détriment des [6]hélicènes attendus. Toutefois, un HBTP fonctionnalisé par des groupements TMS a pu être efficacement préparé, ainsi qu’un hexabenzocoronène (HBC) dont l’exceptionnelle solubilité est due à la distorsion du coeur aromatique sous l’effet des groupements encombrants situés dans les régions baie.Ce fragment [5]hélicène favorisé a enfin été incorporé dans la formulation de nanorubans de carbone tordus, alors composés d’une succession de ce motif. En tant que réactions test, les synthèses du monomère et du dimère correspondants ont été effectuées avec d’excellents rendements et les deux composés entièrement caractérisés. Leurs structures ont été déterminée par diffraction de rayons X sur monocristaux et ont fourni d’intéressantes informations complémentaires quant à leurs configurations. Une stratégie plus générale a enfin été développée et optimisée pour la synthèse systématique d’oligomères plus longs de nanorubans de carbone tordus. En utilisant cette technique les trimère et tétramère correspondants ont été synthétisés et caractérisés par spectrométrie de masse. / Carbon nanoribbons are today of great interest as graphene segments with modulable electronic properties. Whilst top down techniques give giant ribbons, bottom-up organic synthesis may lead to exactly designed nanoribbons of controlled geometries. The Scholl reaction is a precious chemical tool for that purpose since it yields efficiently to the graphitization of long and flexible polyphenylene precursors.Surprisingly, twisted structures may be obtained preferentially even if less crowded isomers are also feasible. It has been shown that, against all expectation, even a strong steric hindrance has no marked effect on regioselectivity and highly twisted polycyclic aromatic hydrocarbons are sometimes preferentially formed, whereas their flat and more symmetrical isomers are only obtained in minority. Highly twisted structures such as hexabenzotriphenylene (HBTP) may then be obtained very easily from flexible polyphenylene precursors.After discovering this unexpected regioselectivity, we used it on purpose to form polyhelicenic species. Attempts to prepared hexaphenanthrotriphenylene (HPTP) were unsuccessful due to reactivity issues when synthesizing the corresponding flexible precursors. By using a new versatile strategy leading to an advanced common precursor, several C3-symmetrical flexible substrates have been synthesized and submitted to Scholl reaction. The expected [6]helicenes were not obtained and rearranged products were formed instead, but TMS-bearing HBTP could be prepared, as well as a hexabenzocoronene (HBC) which exceptionnal solubility is due to the distortion of the aromatic core under the effect of bulky tert-butyl substituents in bay regions.The easily formed [5]helicene fragment has been incorporated in the design of twisted carbon nanoribbons that would be composed of a succession of such motifs. As a test reaction, the corresponding monomer and dimer have been synthesized with an excellent yield and fully characterized. Their X-ray structures have even been determined, giving interesting information about their configuration. A more general strategy has then been developed and optimized for the systematic synthesis of longer oligomers of twisted nanoribbons. Using this technique, the trimer and tetramer have been synthesized and characterized by mass spectrometry.
97

Synthèse régio- et stéréosélective du 4,4,4-trifluorobut-2-énoate d'éthyle porteur d'un groupement tributylstannyl en position alpha ou bêta : réactivité cupro-catalysée des vinylétains en l'absence de complexes du palladium / Regio- and stereoselective synthesis of 4,4,4-trifluorobut-2-enoate carrying a tributylstannyl group in position alpha or beta : copper-catalyzed reactivity of vinyltins in the absence of palladium complexes

Zine, Khalid 16 December 2011 (has links)
Vu l’importance des molécules fluorées dans différents domaines et vu la réactivité engendrée par le 4,4,4-trifluorobut-2-ynoate d’éthyle 1 lors des travaux antérieurs réalisés au laboratoire, nous avons décidé d’étudier le comportement de dérivé fluoré 1 vis-à-vis d’hydrure tributylétain sans l’emploi de catalyseurs ou d’additifs. Le but est d’accéder à de nouveaux synthons fluorés par voies originales.Après une étude préliminaire pour effectuer cette réaction d’hydrostannation dans les meilleures conditions, nous avons réalisé pour la première fois la synthèse totalement régio- et stéréosélective des vinylétains (Z)-2α et (Z)-2β par un simple choix de solvant et sans l’utilisation d’aucun additif. Ces résultats inédits et très encourageants, nous ont conduis à étendre cette stratégie à d’autres hydrures comme l’hydrure de diphénylphosphine et l’hydrure de triphénylgermane..Les vinylétains (Z)-2α et (Z)-2β- de configurations bien définies sont des réactifs de choix pour élaborer de nouvelles structures fonctionnelles trifluorométhylées. En effet, le couplage cupro-catalysé de ces vinylétains en présence d’une quantité catalytique de CuI (10 moles%) avec une variété de bromures d’allyles, de propargyles, d’aryles, de benzyles et d’alcynyles conduisent à une grande variété de composés fluorés jamais décrits dans la littérature.Les méthodes de synthèse développées dans ce travail sont originales et permettent la synthèse d’une grande famille de composés fluorés avec un moindre coût. / The development of a simple method to obtain perfluoroalkylated building blocks for their subsequent utilization in the synthesis of Rf-containing compounds is therefore essential to organofluorine chemistry. Perfluoroalkylated vinyl metals constitute an important class of these building blocks.In order to prepare a new perfluoroalkylated bulding blocks, we investigated transition metal-catalyzed-free hydrostannylation of ethyl 4,4,4-trifluorobut-2-ynoate 1. The hydrostannylation took place smoothly in the absence of additive, providing regioselectively high yields of the corresponding α or β stannylated alkenoates depending on the nature of the solvent used. Indeed, we have demonstrated that the hydrostannylation of 1 in hexane provided the β-stannylated product with high regioselectivity (>95%) and excellent yield (>97%). Using methanol as solvent, total α-regioselectivity of the hydrostannylation of 1 was observed, providing α -tributylstannylacrylate as the sole regioisomer in a nearly quantitative yield.Theses new vinyltins reagents readily undergo copper (I) catalyst coupling reactions with various electrophiles as allyl, propargyl, benzyl and alkynyl bromides to provide good yields of the new corresponding acrylates esters bearing a β-trifluoromethyl group.This method provided a new efficient entry to this important class of compounds
98

Développement de nouveaux analogues structuraux de l’isocombrétastatine A-4 : conception, synthèse et évaluation biologique / Development of news isocombretastatin A-4 derivatives : design, synthesis and biological evaluation

Tréguier, Bret 03 February 2012 (has links)
Lors de son développement, une tumeur ne peut survivre sans passer par une étape invasive afin de subvenir à ses besoins en nutriment et en oxygène. Cette étape, appelé angiogénèse tumorale, conduit à la formation de vaisseaux sanguins dits « tumoraux », différents des vaisseaux sanguins normaux. Afin de stopper la croissance de la tumeur, il est possible de détruire les vaisseaux sanguins tumoraux formés pendant l’angiogénèse tumorale grâce à des molécules antivasculaires. Ces molécules vont désorganiser la structure du vaisseau et diminuer le flux sanguin au sein de la tumeur pour mener à la nécrose de cette dernière. Parmi ces molécules antivasculaires,la prodrogue phosphate de la combrétastatine A-4 naturelle (CA-4) est le composé actuellement le plus efficace(en développement clinique de phase III contre le cancer de la thyroïde). L’isocombrétastatine A-4 (isoCA-4),possédant une structure de type 1,1-diaryléthylène, est un analogue très puissant développé au laboratoire. Cette molécule est isomère de la CA-4 et permet d’obtenir les mêmes activités biologiques que la CA-4. L’objectif de cette thèse est d’étudier ce motif 1,1-diaryléthylène dans le cadre de molécules cytotoxiques en synthétisant et en évaluant in vitro plusieurs séries de molécules de type « iso ». L’autre partie de cette thèse est dédiée à la synthèse d’analogues hétérocycliques de l’isoCA-4, qui permettront de réaliser les premières études de relation structure-activité sur l’isoCA-4, où son cycle B a été remplacé par un hétérocycle. Ce travail nous a permis de confirmer que la structure de l’isoCA-4 peut servir de base de travail pour développer d’autres agents antivasculaires. / For a tumor, the angiogenesis is a vital step for its development. The spread of the tumor is necessary characterized by an extension of the surrounding vasculature, in order to provide the nutriments and the oxygen required to the growth of the tumor. Resulting from the angiogenesis, the new tumorous blood vessels formed represent an excellent target to treat cancer by aiming specifically at the heart of the tumor. By means of vascular disrupting agents (VDA), it is possible to cut the tumor off the blood flow to trigger the necrosis within the tumor. Among the current VDA, the natural combretastatin A-4 (CA-4) is a strong compound that exhibits excellent antitumoral activities. An isomer of the CA-4, the isocombretastatin A-4 (isoCA-4), was developed inour laboratory to propose an alternative and a new family of VDA. The isoCA-4 is characterized by a 1,1-diarylethylene core, which we studied in this thesis, through 3 series of molecules related to this new structure inmedicinal chemistry. We also synthesized heterocyclic analogues of the isoCA-4, in order to explore the capacity of the isoCA-4 to serve as a basis for developing new antimitotic compounds.
99

Isocombrétastatine A-4 : métabolisme, synthèse et propriétés antitumorales de nouveaux analogues azotés / Isocombretastatin A-4 : metabolism, synthesis and antithumoral activities of new analogs

Soussi, Mohamed Ali 23 January 2013 (has links)
La combrétastatine A-4 (CA-4) est une molécule naturelle qui perturbe sélectivement la vascularisation tumorale en se fixant sur la tubuline. Ce composé sous sa forme phosphate est actuellement en développement clinique de phase III et est indiqué dans le traitement du cancer de la thyroïde et de sarcomes aux Etats-Unis. Au sein de notre laboratoire, nous avons identifié et synthétisé un analogue structural simple de la CA-4 : l’isocombrétastine A-4 (isoCA-4) qui conserve l’activité biologique de la CA-4 et est dénuée de problème d’isomérisation lui conférant ainsi une stabilité accrue par rapport à la CA-4.L’objectif de cette thèse a été d’étudier le métabolisme de l’isoCA-4. L’identification et la synthèse des métabolites ont été réalisées avec succès en collaboration avec une équipe de chercheurs Italiens. La suite de ce travail a été tout d’abord dédiée à la synthèse d’analogues de l’isoCA-4 portant le motif N-méthylamine ou N-propylamine à la jonction des cycles A et B. Parmi les composés synthétisés, les diarylamines 3-15 et 3-20 présentent des activités biologiques in vitro similaires à celles de l’isoCA-4. Il nous paru aussi intéressant dans une troisième partie de remplacer le cycle A de l’isoCA-4 par un noyau hétérocyclique retrouvé dans de nombreuses molécules biologiquement actives. Les résultats préliminaires de cytotoxicité et d’inhibition de la polymérisation de la tubuline sont extrêmement prometteurs. / Combretastatin A-4 (CA-4) is a natural molecule that selectively disrupts tumor vasculature by binding to tubulin. Its phosphate prodrug is currently in clinical phase III and is indicated in the treatment of thyroid cancer and sarcomas in USA.In our laboratory, we have identified and synthesized a structural analogue of CA-4 named isocombretastatin A-4 (isoCA-4) that retains the biological activity of CA-4 and is devoid of isomerization problems that increased its stability.The aim of this thesis was first to study the isoCA-4 metabolism. Identification and synthesis of metabolites were successfully achieved in collaboration with an Italian team. Then, in a second part, we synthesized a novel series of analogues isoCA-4 having a N-methylamine or N-propylamine link between the A- and B-rings. Among these compounds, diarylamines 3-15 and 3-20 display in vitro biological activities comparable to those of isoCA-4. Iin a third party, we have replaced the A-ring of isoCA by an heterocyclic ring which was found in many bioactive molecules. Preliminary results including cytotoxicity and inhibition of tubulin polymerization are extremely promising.
100

Couplages pallado-catalysés de N-tosylhydrazones : synthèse d’oléfines apparentées à l’isocombrétastatine A4 / Palladium catalyzed coupling of N-tosylhydrazones : synthesis of olefines related to isocombretastatin A4

Roche, Maxime 04 December 2014 (has links)
Les travaux rapportés dans ce mémoire concernent le développement de nouveaux couplages pallado-catalysés de N-tosylhydrazones ainsi que leurs applications à la synthèse d’analogues de l’isocombrétastatine A4 (isoCA-4). La première partie du manuscrit est consacrée à l’étude de la réactivité de N-tosylhydrazones encombrées dans les couplages avec des halogénures d’aryle. Des conditions ont été mise au point afin d’avoir accès à des molécules 1,1-diaryléthylène ortho/ortho’-disubstituées en relation avec l’isoCA-4. Une autre partie de ce travail est dédiée au développement de réactions tandem impliquant une N-tosylhydrazone. Deux nouvelles transformations sont rapportées, une réaction tandem couplage de Barluenga-couplage de Buchwald-Hartwig, ainsi qu’une réaction tandem couplage de Barluenga-couplage de Suzuki-Miyaura. Dans le dernier chapitre, le couplage oxydatif d’indoles avec les N-tosylhydrazones a été examiné. Les N-vinylindoles synthétisés par ce couplage ont démontré des activités antiprolifératives prometteuses. / This thesis work concerns the development of new palladium catalyzed cross-coupling reactions of N-tosylhydrazones and their applications to the synthesis of isocombretastatin A4 (isoCA-4) analogs. The first part of this work is dedicated to the study of the reactivity of hindered N-tosylhydrazones in coupling with aryl halides. A protocol has been developed to synthesize ortho/ortho’-disubstituted 1,1-diarylethylenes related to isoCA-4. Another part of this thesis is dedicated to the development of tandem reactions involving N-tosylhydrazones. Two new reactions are reported, a Barluenga cross coupling-Buchwald-Hartwig cross coupling tandem reaction as well as a Barluenga cross coupling-Suzuki-Miyaura cross coupling tandem reaction. In the last chapter, oxidative coupling of indoles with N-tosylhydrazones was examined. N-vinylindoles synthesized by this way showed promising antiproliferative activities.

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