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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.
11

Synthesis of Ligands Bearing Poly(ethylene glycol) Chains and Their Application in Catalysis / ポリエチレングリコール鎖を導入した配位子の合成と触媒反応への応用

Satou, Motoi 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第21115号 / 工博第4479号 / 新制||工||1696(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 辻 康之, 教授 近藤 輝幸, 教授 中村 正治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM
12

Conception, synthèses et évaluations biologiques d’inhibiteurs à double cible : ALK et la restriction calorique / Design, synthesis and biological evaluations of inhibitors double target : ALK and caloric restriction

D'Attoma, Joseph 20 November 2013 (has links)
Les lymphomes à grandes cellules anaplasiques ou ALCL (Anaplastic Large-Cell Lymphoma) sont des cancers appartenant à la famille des lymphomes de type non-Hodgkin. La majorité des ALCL est issue d'une translocation t(2;5)(p23;q35) donnant lieu à la formation d'une protéine de fusion appelée NPM-ALK. A ce jour, peu d'inhibiteurs présentent de bonnes activités contre cette protéine chimérique. L'obésité représente un problème socio-médical d'envergure, à la fois pour ses effets directs et indirects ; le surpoids étant un facteur primaire dans de nombreuses maladies, tout particulièrement les diabètes, les accidents cardiovasculaires, le cancer, etc. A contrario, une restriction calorique (RC) est associée à des bénéfices importants en terme de santé. A l'issue de plusieurs criblages, un inhibiteur au motif 2-acylaminothiazole a montré une activité anticancéreuse sur ALK mais également la faculté de mimer la restriction calorique chez C. Elegans. Par conséquent, les travaux de recherche réalisés lors de cette thèse ont concerné la synthèse d'inhibiteurs comportant le squelette 2-acylaminothiazole. Les chromatographies d'affinité effectuées sur deux de nos inhibiteurs ont permis l'identification de cibles principales potentielles dans le cadre de la restriction calorique et des cibles secondaires possibles pour NPM-ALK. Ensuite, la présence d'un atome de brome sur le cycle aromatique a mené à la formation de liaisons C(sp2)-C(sp2), C(sp2)-C(sp) et C(sp2)- N, en utilisant les couplages catalysés par le palladium. Les différentes méthodes de modulation chimique ont conduit à mettre en place une librairie de 134 molécules. Certains d'entres eux et plus précisément ceux possédant un atome de silicium ont démontré une très bonne activité contre ALK et son mutant L1196M. Enfin, des résultats préliminaires ont également été obtenus sur le sujet de la restriction calorique avec quatre composés montrant une réduction du taux de lipides chez C. Elegans / Anaplastic Large-Cell Lymphoma (ALCL) is a type of cancer belonging to the non-Hodgkin family. The majority of ALCL arises from a translocation t(2;5) (p23;35) which leads to the formation of a fusion protein called NPM-ALK. Nowadays, few molecules are known to inhibit the activity of this chimeric protein. Obesity is a major socio-medical problem, for both direct and indirect effects, overweight is a primary factor in many diseases, especially diabetes, cardiovascular events, cancer, etc... In contrast, caloric restriction (CR) is associated with significant benefits in terms of health. After several screenings, one inhibitor based on a 2-acylaminothiazol scaffold showed anticancer activity on the protein ALK but also the ability to mimic caloric restriction in C. Elegans. The aim of this PhD was to develop the synthesis of new inhibitors including the 2-acylaminothiazol scaffold. The affinity chromatography performed on two of our inhibitors was used to identify potential major cellular targets in the process of caloric restriction and secondary cellular targets for NPM-ALK. Then, the presence of a bromo group on the aromatic ring allowed the formation of C(sp2)-C(sp2), C(sp2)- C(sp) and C(sp2)-N bonds, using palladium-catalyzed couplings. The different chemical methodologies afforded the synthesis of a library of 134 molecules. Some of them especially with a silicon atom demonstrated very good inhibitory activity and high selectivity against NPM-ALK and L1196M-NPM-ALK. Finally, preliminary results were also obtained on the subject of calorie restriction with four compounds showing a reduction of lipids in C. Elegans
13

Distinguishing between surface and solution catalysis for palladium catalyzed C-C coupling reactions: use of selective poisons

Richardson, John Michael 15 January 2008 (has links)
This work focuses on understanding the heterogeneous/homogeneous nature of the catalytic species for a variety of immobilized metal precatalysts used for C-C coupling reactions. These precatalysts include: (i) tethered organometallic palladium pincer complexes, (ii) an encapsulated small molecule palladium complex in a polymer matrix, (iii) mercapto-modified mesoporous silica metalated with palladium acetate, and (iv) amino-functionalized mesoporous silicas metalated with Ni(II). As part of this investigation, the use of metal scavengers as selective poisons of homogeneous catalysis is introduced and investigated as a test for distinguishing heterogeneous from homogeneous catalysis. The premise of this test is that insoluble materials functionalized with metal binding sites can be used to selectively remove soluble metal, but will not interfere with catalysis from immobilized metal. In this way the test can definitely distinguish between surface and solution catalysis of immobilized metal precatalysts. This work investigates three different C-C coupling reactions catalyzed by the immobilized metal precatalysts mentioned above. These reactions include the Heck, Suzuki, and Kumada reactions. In all cases it is found that catalysis is solely from leached metal. Three different metal scavenging materials are presented as selective poisons that can be used to determine solution vs. surface catalysis. These selective poisons include poly(vinylpyridine), QuadrapureTM TU, and thiol-functionalized mesoporous silica. The results are contrasted against the current understanding of this field of research and subtleties of tests for distinguishing homogeneous from heterogeneous catalysis are presented and discussed.
14

Nové C-H aktivace a cross-coupling reakce pro modifikace deazapurinových nukleobází / New C-H activations and cross-coupling reactions for modification of deazapurine nucleobases

Sabat, Nazarii January 2017 (has links)
This PhD thesis reports the development of novel C-H activation strategies and aqueous-phase Suzuki-Miyaura cross-coupling reactions for the synthesis of modified deazapurine nucleobases. The methodologies of chemo- and regioselective synthesis of highly functionalized deazapurines have been developed by using modern C-H activation chemistry. Various functional groups such as amino-, imido-, silyl- and phosphonyl- were introduced by C-H activation reactions. Amino deazapurine derivatives were synthesized by developed Pd/Cu-catalyzed direct C-H amination and C-H chloroamination of 6-substituted 7-deazapurines with N-chloro-N- alkyl-arylsulfonamides. C-H imidation reactions of pyrrolopirimidines were performed under ferrocene catalysis with N-succinimido- or N-phtalimidoperesters. In order to obtain silylated derivatives, Ir-catalyzed C-H silylations of phenyldeazapurines with alkyl silanes were designed. Highly interesting deazapurine phosphonates were prepared by using Mn-promoted C-H phosphonation method and were further transformed into the corresponding phosphonic acids. All of the developed direct C-H functionalization reactions proceeded regioselectively at position 8 in deazapurine core, except for C-H silylation where reaction undergoes mainly as directed ortho C-H silylation on phenyl ring,...
15

A Novel Method for the Synthesis of Indolo[2,1-a]isoquinolines

Lotter, Angelique Natalia Cassandra 31 October 2006 (has links)
MSc dissertation School of Chemistry Faculty of Science 0004984F / Many azapolycyclic aromatic ring systems, whether they are naturally occurring or synthetically made, display important biological activities. One important class of naturally occurring azapolycyclic aromatic ring systems are the dibenzopyrrocoline alkaloids, which contain an indole ring fused to an isoquinoline moiety, where they share a common nitrogen. The basic skeleton of these alkaloids is the indolo[2,1-a]isoquinoline nucleus. Both the dibenzopyrrocoline alkaloids and the indolo[2,1-a]isoquinolines have been found to inhibit tubulin polymerization and thus possess antitumour and antileukemic activities. In our laboratories, a variety of indolo[2,1-a]isoquinolines, for example 5,12- dimethyl-6-phenylindolo[2,1-a]isoquinoline, have been synthesized using the Suzuki-Miyaura cross coupling reaction and reaction conditions for the formation of aromatic rings (KOBut in DMF and a light source – developed in our laboratories) as key steps. In this dissertation we discuss the synthesis of (±)-5,6-dihydro-6-phenylindolo[2,1-a]isoquinolin-5-ol and ethyl indolo[2,1- a]isoquinoline-6-carboxylate using these reaction conditions as our key steps. The syntheses commenced with the N-protection of isatin with a benzyl and an ethyl acetate group to afford 1-benzylindoline-2,3-dione and ethyl 2-(2,3- dioxoindolin-1-yl)acetate respectively. The next step was the synthesis of the brominated compounds 1-benzyl-2-bromo-1H-indole and ethyl 2-(2-bromo- 1H-indol-1-yl)acetate by means of a functional group interconversion of the oxygen in the 3-position to two chlorine atoms, followed by hydrodehalogenation, using zinc in AcOH, and then bromination, using POBr3 in CH2Cl2. Having obtained the brominated compounds we went on and coupled them with 2-formylphenylboronic acid using the Suzuki-Miyaura cross coupling reaction to obtain the coupled products 2-(1-benzyl-1H-indol-2- yl)benzaldehyde and ethyl 2-(2-(2-formylphenyl)-1H-indol-1-yl)acetate in 92 and 77% yield, respectively. Aromatisation of ethyl 2-(2-(2-formylphenyl)-1Hindol- 1-yl)acetate to ethyl indolo[2,1-a]isoquinoline-6-carboxylate occurred smoothly in 2 minutes using 10 mol % KOBut in DMF at room temperature. Using the same reaction conditions on 2-(1-benzyl-1H-indol-2- yl)benzaldehyde to form 6-phenylindolo-[2,1-a]isoquino-line resulted in (±)- 5,6-dihydro-6-phenylindolo[2,1-a]iso-quinolin-5-ol being obtained in 75% yield (7:3 ratio of anti:syn). An attempt to dehydrate this compound using p-TSA in CH2Cl2 in the presence of molecular sieves was not successful. Time constraints prevented any further attempts at dehydrating (±)-5,6-dihydro-6- phenylindolo[2,1-a]iso-quinolin-5-ol. In conclusion, we managed to synthesize (±)-5,6-dihydro-6-phenylindolo[2,1- a]isoquinolin-5-ol and ethyl indolo[2,1-a]isoquinoline-6-carboxylate using the Suzuki-Miyaura cross coupling reaction and specific reaction conditions, using the base KOtBu, for the formation of aromatic rings, both as key steps.
16

Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolines

Lesenyeho, Lehlogonolo Godfrey 09 1900 (has links)
The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis. / Chemistry / MSc. (Chemistry)
17

2-Aryl-6,8-Dibromo-4-Chloroquinazoline as scaffold for the synthesis of Novel 2,6,8-Triaryl-4-(Phenylethynyl)Quinazolines with potential photophysical properties

Paumo, Hugues Kamdem 06 1900 (has links)
The 2-aryl-6,8-dibromoquinazolin-4(3H)-ones were prepared in a single-pot operation by condensing 6,8-dibromoanthranilamide and aryl aldehydes in the presence of molecular iodine in ethanol. Treatment of the 2-aryl-6,8-dibromoquinazolin-4(3H)-ones with thionylchloride in the presence of dimethylformamide afforded the corresponding 2-aryl-4-chloro-6,8-dibromoquinazolines. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling reaction of 2-aryl-4-chloro-6,8-dibromoquinazolines with terminal alkynes at room temperature afforded series of 2-aryl-6,8-dibromo-4-(alkynyl)quinazolines. Further transformation of the 2-aryl-6,8-dibromo-4-(phenylethynyl)quinazolines via Suzuki-Miyaura cross-coupling with arylboronic acids occurred without selectivity to afford the corresponding 2,6,8-triaryl-4-(phenylethynyl)quinazolines. The compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques as well as mass spectrometry. The absorption and emission properties of 2,6,8-triaryl-4-(phenylethynyl)quinazolines were determined in solution. / Chemistry / M.Sc. (Chemistry)
18

Palladium-catalyzed heteroannulation of 2-ARYL- 3-IODO-4-(Phenylamino)quinolines and 4-(N,N-allylphenylamino)-2-ARYL-3-iodoquinolines

Lesenyeho, Lehlogonolo Godfrey 09 1900 (has links)
The previously described 2-aryl-4-chloro-3-iodoquinolines were prepared following literature procedure and in turn converted to the corresponding hitherto unknown 2-aryl-3-iodo-4-(phenylamino)quinoline derivatives using aniline in refluxing ethanol. These 2-aryl-3-iodo-4-(phenylamino)quinolines were reacted with allybromide in ethanol at room temperature to afford 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives. The 2-aryl-3-iodo-4-(phenylamino)quinoline and 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were subjected to metal-catalysed carbon-carbon bond formations. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling of 2-aryl-3-iodo-4-(phenylamino)quinoline with terminal alkynes afforded series of 1,2,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines in a single step operation. On the other hand, the 4-(N,N-allylphenylamino)-2-aryl-3-iodoquinoline derivatives were found to undergo palladium-catalysed intramolecular Heck reaction to yield the corresponding 1,3,4-trisubstituted 1H-pyrrolo[3,2-c]quinolines. All new compounds were characterized by using a combination of NMR (1H and 13C), IR, mass spectroscopic techniques as well as elemental analysis. / Chemistry / MSc. (Chemistry)
19

2-Aryl-6,8-Dibromo-4-Chloroquinazoline as scaffold for the synthesis of Novel 2,6,8-Triaryl-4-(Phenylethynyl)Quinazolines with potential photophysical properties

Paumo, Hugues Kamdem 06 1900 (has links)
The 2-aryl-6,8-dibromoquinazolin-4(3H)-ones were prepared in a single-pot operation by condensing 6,8-dibromoanthranilamide and aryl aldehydes in the presence of molecular iodine in ethanol. Treatment of the 2-aryl-6,8-dibromoquinazolin-4(3H)-ones with thionylchloride in the presence of dimethylformamide afforded the corresponding 2-aryl-4-chloro-6,8-dibromoquinazolines. Palladium(0)-copper iodide catalysed Sonogashira cross-coupling reaction of 2-aryl-4-chloro-6,8-dibromoquinazolines with terminal alkynes at room temperature afforded series of 2-aryl-6,8-dibromo-4-(alkynyl)quinazolines. Further transformation of the 2-aryl-6,8-dibromo-4-(phenylethynyl)quinazolines via Suzuki-Miyaura cross-coupling with arylboronic acids occurred without selectivity to afford the corresponding 2,6,8-triaryl-4-(phenylethynyl)quinazolines. The compounds were characterized using a combination of NMR (1H and 13C) and IR spectroscopic techniques as well as mass spectrometry. The absorption and emission properties of 2,6,8-triaryl-4-(phenylethynyl)quinazolines were determined in solution. / Chemistry / M.Sc. (Chemistry)
20

Synthèse et applications de nouveaux complexes métallocéniques multidentes / Synthesis and applications of new multidentate metallocenic complexes

Allouch, Fatima 29 January 2013 (has links)
Ce mémoire porte sur l’accès simple et peu coûteux à de nouveaux ligands ferrocéniques aminés et aminophosphinés et leur coordination avec des métaux de transition pour des applications en catalyse homogène.Des métallo-ligands aminés flexibles ont été obtenus et caractérisés après amination réductrice du 1,1’-diformylferrocène. D’autres ligands (N,N) rigides ont été isolés au départ du précurseur du 1,1’-di-tert-butyl-3,3’-diformylferrocène. Des aza-ferrocénophanes ont également été facilement préparés avec ces deux précurseurs carbonylés. Lors de la coordination de ces ligands avec le palladium, un palladacycle original a été isolé et caractérisé par diffraction de rayons X.Des ligands ferrocéniques (N,P) ont été obtenus par trois méthodes: i) ortholithiation de ligands ferrocéniques aminés suivie d’un ajout de chlorophosphine, ii) amination réductrice des ferrocènes formylés substitués ou non en présence d’amine portant une fonction phosphine, iii) substitution directe du ferrocène dilithié par des chlorophosphines comportant un hétérocycle azoté. Leur coordination avec du palladium et du platine a été étudiée. Ces métallo-ligands hybrides ont été impliqués dans des réactions de chlorures d’aryle avec des acides arylboroniques (couplage de Suzuki), ainsi que dans la réaction de Sonogashira avec le couplage de bromures et de chlorures d’aryle avec le phénylacétylène / This thesis focuses on simple and inexpensive access to new amino and aminophosphine ferrocenyl ligands and their coordination with transition metals for applications in homogeneous catalysis.Flexible amine metallo-ligands were obtained and characterized after reductive amination of 1,1'-diformylferrocene. Other rigid (N,N) ligands were isolated starting from the precursor 1,1'-di-tert-butyl-3, 3'-diformylferrocene. Aza-ferrocenophanes were also easily prepared with these two formyl precursors. During the coordination of these ligands with palladium, a stable and original palladacycle was isolated and characterized by DRX.(N,P) ferrocenyl ligands were obtained by three methods: i) ortholithiation of aminoferrocenyl ligands followed by addition of chlorophosphines, ii) reductive amination of substituted or not formylferrocene in the presence of amine bearing a phosphine function, iii) direct substitution of dilithiated ferrocene by chlorophosphines with a nitrogen-containing heterocycle. Their coordination with palladium and platinum has been studied. These hybrid metallo-ligands have been implicated in the reactions of aryl chlorides to arylboronic acids (Suzuki cross-coupling), as well as in the Sonogashira reaction involving of coupling aryl bromides and chlorides to phenylacetylene

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