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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.
171

Síntese de derivados de chalconas e de 2-quinolinonas visando a busca por inibidores das enzimas cruzaína e da família BET bromodomain / Synthesis of chalcone and 2-quinolinone derivatives towards the development of new cruzain and BET bromodomain enzyme inhibitors

Vieira, Lucas Campos Curcino 12 September 2014 (has links)
Made available in DSpace on 2016-06-02T20:34:55Z (GMT). No. of bitstreams: 1 6228.pdf: 15112297 bytes, checksum: 74610acef15a4b7ec7b835eff728f13f (MD5) Previous issue date: 2014-09-12 / Universidade Federal de Minas Gerais / The first part of this work involved the synthesis of chalcone derivatives towards the development of inhibitors of the enzyme cruzain from Trypanosoma cruzi. Different green chemistry approaches were employed to functionalize chalcones as the use of alternative solvents as well as source of energy. A new Suzuki cross-coupling methodology for synthesis of functionalized chalcones was developed, employing PEG-400 as solvent under microwave irradiation. The use of organocatalysis in the 1,4-addition of α,α-dicyanoolefins to α,β- unsaturated carbonyl system provided products with good yields and excellent enantiomeric excess. It was also developed a new synthetic route for the synthesis of γ-butenolides from chalcones. The key step was accomplished using montmorillonite K10 clay as catalyst and ethanol as solvent... (CONTINUE) / A primeira parte deste trabalho teve como objetivo a síntese de derivados de chalconas visando a busca por inibidores da enzima cruzaína de Trypanossoma cruzi, causador da Doença de Chagas. Foram abordadas reações químicas para a funcionalização de chalconas empregando princípios de química verde como o uso de fonte de energia e solventes alternativos. Foi desenvolvida uma nova metodologia de acoplamento cruzado de Suzuki para a síntese de chalconas funcionalizadas, empregando PEG-400 como solvente sob irradiação de micro-ondas. O emprego da organocatálise na adição de α,α- dicianoolefinas ao sistema carbonílico α,β-insaturado forneceu produtos com bons rendimentos e ótimos excessos enantioméricos. Foi também elaborada uma nova rota sintética para a síntese de γ-butenolídeos, partindo de chalconas. A última etapa reacional foi realizada utilizando a argila montmorillonite K10 como catalisador e etanol como solvente... (CONTINUA)
172

O teatro de Tadashi Suzuki e o ator como eixo de sua poética cênica

Castilho, Patrícia Lima [UNESP] 22 June 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-06-22Bitstream added on 2014-06-13T20:07:38Z : No. of bitstreams: 1 castilho_pl_me_ia.pdf: 1011777 bytes, checksum: 0826b5cd2a5a9b6a012fed90feeb1396 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / A proposta desse trabalho é promover uma reflexão acerca do encenador japonês Tadashi Suzuki (Japão, 1939-) no que diz respeito a sua contribuição para a arte do teatro e, mais especificamente, à questão da expressividade do ator. Suzuki parte da ideia da atuação como a expressão da consciência do ator numa investigação constante acerca da própria condição humana. Este trabalho pretende averiguar o papel do ator e a sua articulação com os demais elementos da poética cênica daquele que é considerado um dos maiores pensadores do teatro e da atuação na contemporaneidade / The purpose of this work is to promote a reflection on the Japanese director Tadashi Suzuki (Japan, 1939-) as regards his contribution to the art of theatre and, more specifically, the issue of actor’s expressiveness. Suzuki starts from the idea of performance as the expression of the actor’s consciousness in a constant research about the human condition. This work intends to investigate the role of the actor and his relationship with other elements of poetic scenic of a man who is considered one of the greatest thinkers of theatre and performance in contemporary times
173

Estudo teorico do mecanismo de acoplamento-cruzado envolvido na reação de formação da ligação Ph-Ph catalisada por paladio via PhB (OH)2 (Ph=C6H5) / Theoretical studyng of cross coupling mechanism presented in palladium-catalized Ph-Ph bond formation reaction by PhB (Oh)2 (Ph=C6H5)

Silva, Maurício Chagas da 28 February 2005 (has links)
Orientador: Nelson Henrique Morgon / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica / Made available in DSpace on 2018-08-04T16:59:18Z (GMT). No. of bitstreams: 1 Silva_MauricioChagasda_M.pdf: 1448929 bytes, checksum: 5e8a626133912c0e72a209eeccbbfd34 (MD5) Previous issue date: 2005 / Mestrado / Físico-Química / Mestre em Química
174

Approches synthétiques de la Dasyscyphine D et du Laingolide A / Synthetic approaches of Dasyscyphin D and Laingolide A

Lemaire, Gaétan 12 November 2014 (has links)
Ce manuscrit présente une approche synthétique de deux produits naturels, la Dasyscyphine D et le Laingolide A. En ce qui concerne la Dasysyphine D, nous avons étudié une étape-clé de cycloaddition de Diels-Alder entre un diène et un diénophile, préparés par des réactions de couplage pallado-catalysées et/ou de métathèse cyclisante. Pour le Laingolide A, plusieurs isomères ont été synthétisés dans le but de déterminer la configuration relative des trois centres stéréogènes. Cette synthèse fait intervenir une réaction tandem dimérisation croisée/oxonia-Cope et une macrocyclisation finale formant un motif énamide. / This manuscript presents the synthetic approach of two natural products, Dasyscyphin D and Laingolide A. Concerning Dasysphin D, the key step of the synthesis is a Diels-Alder cycloaddition between a diene and a dienophile, which were prepared by palladium-catalyzedcross coupling and/or metathesis reactions. For Laingolide A, several isomers have been synthesized in order to determine the relative configuration of the three stereogenic centers.This synthesis involves a tandem cross dimerization/oxonia-Cope reaction, and a final macrocyclization to install the enamide moiety.
175

Syntheses and catalytic properties of palladium (II) complexes of various new aryl and aryl alkyl phosphane ligands

Vuoti, S. (Sauli) 27 November 2007 (has links)
Abstract Thirty three aryl and aryl alkyl phosphane ligands were prepared and characterized for catalytic purposes. The aryl groups in both types of ligands were modified with alkyl substituents (methyl, ethyl, isopropyl, cyclohexyl, phenyl) or hetero substituents (methoxy, N,N-dimethylaniline, thiomethyl). The alkyl groups directly attached to the phosphorous atom were ethyl, isopropyl or cyclohexyl. Mono- and in some cases also dinuclear palladium (II) complexes of the ligands were prepared and characterized. The syntheses of the palladium complexes are solvent-dependent and afford either mono- or dinuclear complexes depending on the choice of the solvent. Additionally, two 2-mercaptobenzothiazole palladium complexes were synthesized and characterized. A rare distorted lantern-type structure was presented for the first time. The ligands were characterized by 1H, 13C, 31P NMR spectroscopy and mass spectrometry. The palladium complexes were characterized by 31P NMR spectroscopy, X-ray crystallography and elemental analysis. Links between the NMR data of the palladium complexes and ligands and their catalytic activity was screened and correlation found. The crystal structures of the palladium complexes were studied for possible attractive interactions between two ligands. Such interactions were found from two examples. There is an attractive interaction between the phenyl and quinolinyl moieties of 2-quinolinyldiphenyl phosphane. A similar interaction was found between the methyl substitute and phenyl ring of o-tolylphosphane. The ligands and palladium complexes presented in this thesis were prepared in hope of finding suitable catalysts for Suzuki coupling reactions of various bulky aryl halides and phenyl boronic acids to prepare sterically hindered bi- and triaryls under microwave irradiation. A selection of aryl alkyl phosphane ligands catalyzed the couplings of bulky aryl bromides and even unactivated aryl chlorides efficiently and produced high yields. The reaction conditions of a new catalyst system were optimized, and it was noticed that the addition of a small amount of water enhanced the purity and yield of the coupling products further.
176

Suzuki Tadashi's Intercultural Adaptations

Guertin, Caroline Aki Matsushita January 2015 (has links)
Contemporary theatre is increasingly visual, an aesthetic shift that has been analyzed in, among others, Hans-Thies Lehmann’s influential Postdramatic Theatre. This shift is apparent in Japanese director Tadashi Suzuki’s intercultural adaptations, which adapt plays of the Western repertoire for contemporary Japanese and international audiences in a style that is richly and evocatively visual. Notions drawn from postdramatic theatre, metatheatre and postcolonial theories are applied as framing devices to uncover the deep cultural and theatrical significance of Suzuki’s adaptive work. My approach to analyzing the three case studies: Suzuki’s King Lear, The Trojan Women, and Cyrano de Bergerac takes a more globalized view of theatrical adaptations that acknowledges the visual turn of contemporary theatre and contributes to the fields of intercultural performance studies and adaptation studies by expanding the notion of interculturalism beyond the limits imposed by current Western analytical perspectives.
177

Nouveaux ligands issus de dianhydrohexitols : évaluation en catalyse organométallique pour le couplage biarylique atroposélectif / New ligands from dianhydrohexitols : application in organometallic catalysis for atroposelective biarylic coupling

Maunoury, Thibault 16 December 2013 (has links)
Nombreux produits naturels ou non possédant des propriétés biologiques variées. De même, les composés de ce type ont été largement utilisés en catalyse asymétrique principalement comme ligands.Ce travail de thèse repose sur le développement de nouveaux ligands issus de la biomasse et plus particulièrement de deux dianhydrohexitols l’isomannide et de l’isoidide en vue de leur évaluation pour le couplage atroposélectif de composés biaryliques.Deux familles de ligands diamines ont été formées. Ils appartiennent soit à la série isoidide, les deux groupements azotés étant en position exocyclique soit à la série isomannide ceux ci étant fixés en position endocyclique.Ces divers composés ont été utilisés comme ligands du cuivre (I) dans le couplage oxydant decomposés biaryliques (couplage du 2-naphtol et du 2-hydroxy-3-naphtoate de méthyle). Les meilleurs résultats ont été obtenus en série isomannide à l’aide d’une diamine primaire. Ainsi un excès énantiomérique maximun de 15% a été observé lors de la formation du BINOL en présence d’iodure de cuivre. Quant au couplage du 2-hydroxy-3-naphtoate de méthyle catalysée avec le chlorure de cuivre 76% de rendement avec 69% d’excès énantiomérique ont été obtenus. Pour ce dernier, en série isoidide, les rendements restent faibles et les excès ne dépassent pas les 15%. Cette différence de comportement à été attribuée à la formation possible d’un complexe mettant en jeu un ligand bidente. Ce dernier ne peut se former qu’en série isomannide ; la distance déterminée à l’aide du logiciel SPARTAN entre les deux groupements amine primaire étant de l’ordre de 4,9 Å alors que celle indiquée pour la série isoidide de l’ordre de 5.9 Å. Les meilleures conditions ont été mises à profit pour étudier d’autres homocouplages de 2-hydroxyestersnaphtoïques ainsi que des couplages croisés.En complément de ce travail, une étude préliminaire de couplage de Suzuki catalysée au palladium a été initiée. Elle met en jeu des ligands phosphorés comportant un seul motif tétrahydrofuranique ou conservant la structure bicyclique des dianhydrohexitols ainsi que des ligands diazotés. / Chiral biarylic paterns are present in severalnatural products or in compounds present biologicalproperties. This type of compounds was also used inasymmetric catalysis.This work is based on the developpement ofnew ligands from biomass mainly from twodianhydrohexitols, isomannide and isoidide, and theirevaluation in atroposelective coupling of birayliccompounds.Two families of diamine ligands were formed.They belong to isoidide series or isomannide series,where the two substituants are respectively in exocyclicand in endocylic position.These compounds were used as copper (I)ligands for oxidative coupling of biarylic compounds(coupling of 2-naphtol and methyl 2-hydroxy-3-naphtoate).During BINOL formation, a maximumenantiomeric excess of 15% was observed in thepresence of copper iodide. With methyl 2-hydroxy-3-naphtoate in the presence of copper chloride, 69% ofenantiomeric excess and 76% of yield were observed.With ligands from isoidide series, yields are weak andthe excess does not exceed 15% for the last substrate.This behavior could be explained by the formation of acopper complex with a bidentate ligand. This complexcan be formed only in isomannide series; the distancebetween the two primary amines, calculated withSPARTAN software, was found around 4.9 Å forisomannide series and 5.9 Å for isoidide series. Thebest conditions were involved in the study ofhomocoupling of naphtoic 2-hydroxyesters and crosscoupling.In addition to this work, a preliminary study ofthe Suzuki coupling involving phosphorous ligandspresenting a single tetrahydrofuranic ring or keepingbicycle of dianhydrohexitol structures along withdinitrogen ligands were evluated.
178

Approaches toward the synthesis of lactonamycin utilising a new benzannulation reaction

Hussain, Jakir January 2013 (has links)
The Bull-Hutchings-Quayle (BHQ) reaction is a novel method for the synthesis of 1-(bromo/chloro)napthalenes from 2-allyphenyl-2’,2’,2’-tri(bromo/chloro)acetates. The reaction is also known as Atom Transfer Radical Cyclisation-Benzannulation (ATRC-Benzannulation). The ATRC-Benzannulation of structurally diverse 2-(cyclohex-1-en-1-ylmethyl)phenyl 2’,2’,2’-trichloroacetates in the presence of 1,3bis-(2,6diisopropylphenyl)imidazolium copper(I) chloride [“Nolan NHC-CuCl”] complexes, using microwave or thermolytic methods, afford a range of 9-chloro-1,2,3,4-tetrahydroanthracenes. Efficient ATRC-Benzannulation has been restricted to microwave conditions so a thermolytic method has been developed as an alternative. Application of BHQ methodology toward the synthesis of the core structure of lactonamycin are reported. Stille, Suzuki and Sonogashira cross-coupling methods were used for the synthesis of diene precursors of a lactonamycin analogue. [4+2] Diels-Alder cycloadditions have been investigated with the diene precursors and various dienophiles. 1-Chloroquinone has been displaced with para-methoxyphenol to generate 1-para-methoxyquinone. CAN mediated oxidation of 1-para-methoxyquinone has yielded 1-hydroxyquinone.
179

Enzymatic Post-Translational Halogenation for Adding Functionality to Biomaterials

Compean, Alexander L. 24 August 2021 (has links)
No description available.
180

Aktivita nových komplexů niklu v couplingových reakcích / Activity of new nickel-complexes in coupling reactions

Plaček, Martin January 2010 (has links)
In this work, we report the study of the catalytic activity of newly prepared coordination compounds of nickel(II) (complexes were prepared by prof. Kyritsis, University of Athens). The activities in model reactions of Kumada and Suzuki coupling and polymerization of 2,5- dibromo-3-hexylthiophene were tested. For Kumada coupling, the activity is comparable with known complex [Ni(dppp)Cl2]. On the other hand, selected complexes exhibit only limited activity for Suzuki coupling. GRIM polymerization of 2,5-dibromo-3-hexylthiophene was successful. Properties of prepared polymers are comparable with polymers prepared via known route with [Ni(dppp)Cl2].

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