Conselho Nacional de Desenvolvimento Científico e Tecnológico / Nesse trabalho foram realizadas reações de substituição nucleofílica (SN2), utilizando aquecimento térmico convencional e por irradiação de micro-ondas (MO), de alguns átomos cloro em amostras comerciais de poli(cloreto de vinila) (PVC), por grupos nitrila e também por grupos azida. Os grupos nitrila e azida foram substituidos na matriz em diferentes teores (10% e 20%). As reações do PVC com azida foram eficazes, apresentado percentuais de derivatização muito próximos dos valores desejados. Já no estudo com a nitrila não foi obtido o resultado esperado. Os copolímeros PVC azido substituídos foram modificados com propargilato de etila, sob catálise de iodeto de cuproso (CuI), para a obtenção de heterocíclicos do tipo triazólicos. Todos os copolímeros obtidos foram caracterizados por espectroscopia na região do infravermelho (FTIR) e os teores de nitrogênio incorporado foram determinados por análise elementar (AE). Através da análise dos dados obtidos, foi comprovado que a utilização da irradiação micro-ondas, quando comparada ao aquecimento convencional, é um processo mais seletivo e diminui, significativamente, os tempos de reação / In this work we had performed nucleophilic substitution reactions (Sn2) of some chlorine atoms in commercial samples of poly (vinyl chloride) (PVC), nitrile groups and also by azide groups, using both conventional thermal heating and microwave irradiation (MW).Nitrile and azide groups were replaced in the matrix at diverse levels (10% and 20%). The reactions of PVC with azide were effective, reaching a percentage derivatization very near to the desired values. In the study with the nitrile although we have not obtained the expected results. The substituted azido copolymers were modified with propargilato acetate, under catalysis of copper iodide (CuI) to obtain triazole heterocyclic type. All copolymers were labeled by infrared spectroscopy (FTIR) and nitrogen contents were determined by corporate elemental analysis (EA). Through analysis of the data obtained, it was verified that the use of microwave irradiation in comparison to conventional heating is a more selective process and reduces significantly reaction times

O objetivo deste trabalho é explorar a síntese e funcionalização de 1,2,3- triazóis empregando o uso de reações do tipo \"Click-chemistry\", que é uma abordagem para a síntese de diversos compostos com base em reações de formação de ligação carbono-heteroátomo, onde a reação é estereoespecífica, altamente eficiente e geralmente com elevados rendimentos e em alguns casos ausência de subprodutos. O composto 1,2,3-triazol, sendo o material de partida para a continuidade do projeto foi preparado a partir do álcool propargílico (4) em presença de uma azida orgânica (1) e utilizando cobre(I) como agente promotor. Após a obtenção de uma série de compostos 1,2,3-triazólicos (2), procedeu-se a etapa de tosilação da hidroxila e posterior cicloadição multicomponente de um novo 1,2,3-triazol formando compostos bis-triazólicos. Os bis-triazóis (5) obtidos foram testados frente a cepas fúngicas, responsáveis por dermatites, com resultados satisfatórios. Ainda essas estruturas poderão ser empregados como blocos construtores para a síntese de estruturas mais complexas. / The aim of this work has been exploring the synthesis and functionalization of 1,2,3-triazoles employing the use of \"click-chemistry\" concept, which is defined as an approach for synthesis of various compounds based on reactions of carbon-heteroatom bond formation, which the reaction is stereospecific, high-efficiently, commonly gives high yields and in some cases no by-products are formed. The compound 1,2,3-triazole, which is the main starting material for the next steps was prepared from propargyl alcohol (4) in the presence of an organic azide (1) and copper(I) as a reaction promoter. Subsequently with a series of 1,2,3-triazole (2n) prepared we proceeded to the next step which is the substitution of hydroxyl for a tosyl group and after that a multicomponent cycloaddition of a new 1,2,3-triazole compound forming bis-triazoles. Bis-triazoles (5) were tested against fungal strains, responsible for dermatitis, with delighted results, furhtermore this class of strutures can be used as building blocks to improve efficiency in some other more complex structure.

A funcionalização de 3,4,6-tri-O-acetil-D-glucal foi realizada utilizando reações de acoplamento cruzado (Sonogashira e Stille), ciclo-adições de azida-alcino (Click chemistry) e ciclização nucleófila promovida por eletrófilo. Utilizando estas reações juntamente com as já referidas transformações de grupos funcionais e reações de rearranjo de Ferrier, as bibliotecas de compostos à base de glucal foram sintetizadas e observadas em algumas moléculas fluorescência e outras foram disponibilizadas para avaliação de atividade biológica. Na primeira parte, foram sintetizadas bibliotecas de derivados de bis- e tris-triazolil-glicosila a partir de 3,4,6-tri-O-acetil-D-glucal utilizando as reações acima mencionadas. A segunda parte deste trabalho consiste em sintetizar uma biblioteca de derivados glucal de 2-alquinilo usando um acoplamento de Sonogashira livre de cobre e ligante, seguido por aplicações sintéticas destes alquinos glucais. A hidrostanação regioselectiva catalisada por paládio destes glucanos 2-alquinilo foi realizada utilizando hidreto de tributilestanho para gerar uma biblioteca de derivados estanil regioisoméricos de glucal. Além disso, estes derivados de 2-alquinil-glucal sintetizados na primeira parte também foram utilizados na ciclização nucleofílica 5-endo-dig promovida por eletrófilos para proporcionar derivados de glucal bicíclicos. Na parte final, os derivados de estanho de glucal foram utilizados para sintetizar bibliotecas de derivados de 2-alcenil glucal substituído. Esta parte inclui também transformações de grupos funcionais e acoplamentos cruzados (Stille e Sonogashira), bem como click chemistry para gerar bibliotecas de derivados de 2-alquenil-D-glucal alquinilo e triazolilo substituídos. Na maioria dos casos os produtos foram obtidos em rendimentos muito bons a excelentes que foram analisados utilizando RMN, Infra vermehlo, espectrometria de massas de alta resolução e outras técnicas analíticas quando aplicável. / Functionalization of 3,4,6-tri-O-acetyl-D-glucal has been performed using cross-coupling (Sonogashira and Stille) reactions, azide-alkyne cycloadditions (Click chemistry) and electrophile-promoted nucleophilic alkyne cyclizations. Using these reactions along with the already reported functional group transformations (FGT) and Ferrier rearrangement reactions, libraries of glucal-based compounds were synthesized with members of characteristic photophysical and potential biological properties. In the first part, the synthesis of libraries of bis- and tris-triazolyl glycosyl derivatives is described starting from 3,4,6-tri-O-acetyl-D-glucal using the above-mentioned reactions. In the second part of this work, the synthesis of a library of 2-alkynyl glucal derivatives using a copper and ligand-free Sonogashira coupling, followed by synthetic applications of these glucal alkynes is reported. Palladium-catalyzed regioselective hydrostannation of these 2-alkynyl glucals was performed using tributyltin hydride to generate a library of regioisomeric stannyl derivatives of glucal. Moreover, these 2-alkynyl glucal derivatives synthesized in the first part were also used in electrophile-promoted nucleophilic 5-endo-dig cyclization to afford bicyclic glucal derivatives. In the final part, the use of stannyl derivatives of glucal to synthesize libraries of substituted 2-alkenyl glucal derivatives is described. This part also includes certain functional group transformations and cross-couplings (Stille and Sonogashira) as well as click chemistry to generate libraries of alkynyl and triazolyl substituted 2-alkenyl-D-glucal derivatives. In most of the cases, the products were obtained in very good to excellent yields and were analyzed using 1H NMR, 13C NMR, FTIR, HRMS, and other analytic techniques where applicable

Peptídeos são biomoléculas que apresentam extensa variedade estrutural e funcional, atuando em diversos processos biológicos relevantes. Estas moléculas são amplamente utilizadas na terapêutica, constituindo, atualmente, um campo investigativo bastante promissor para o desenvolvimento de novos fármacos, especialmente no desenvolvimento de vacinas sintéticas. Os avanços científicos relacionados às técnicas de identificação, análise e purificação tem estimulado diversas pesquisas na busca por fármacos baseados em peptídeos, os quais podem ser obtidos a partir de fontes naturais ou por métodos químicos (em solução ou em fase sólida), enzimático ou combinação de ambos (semi-síntese) e via tecnologia do DNA recombinante. Entretanto, devido às limitações próprias dos peptídeos naturais, tais como, suscetibilidade proteolítica, toxicidade e baixa biodisponibilidade, torna-se necessária a síntese de peptídeos modificados. Como a função biológica de um peptídeo é definida por sua conformação estrutural, a inserção de modificação em uma estrutura peptídica deve ser capaz de manter ou estabilizar esta conformação estrutural. O desenvolvimento de novas e eficientes rotas de síntese de peptídeos modificados torna-se necessário para superar as limitações relacionadas à suscetibilidade proteolítica, toxicidade e baixa biodisponibilidade, afim de contribuir para novas estratégias terapêuticas, em especial no desenvolvimento de vacinas. Desta forma, a inserção de grupo 1,2,3-triazol tem fornecido propriedades físicoquímicas desejáveis no desenvolvimento de fármacos. O objetivo deste trabalho foi desenvolver um método de síntese de peptídeos contendo grupo 1,2,3-triazol 1,4- dissubstituído, como o peptídeo 1, o qual é constituído por dezesseis resíduos de treonina e um grupo 1,2,3-triazol 1-4-dissubstituído entre os resíduos Thr8 e Thr9 (NH2-(Thr)7-Thr-(ciclo 1,2,3-triazol 1,4-dissubstituído)-Thr-(Thr)7-OH). Adicionalmente, devido à semelhança com mucinas de T. cruzi, as quais apresentam rica composição em resíduos de treonina, 1 poderá ser empregado na preparação de peptideomiméticos destas mucinas e no desenvolvimento de vacinas relacionadas à processos infecciosos causados por T. cruzi. A preparação de 1 envolveu uma associação entre síntese de peptídeo em fase sólida e reações de ciclo-adição azido-alcino 1,3 dipolar catalisada por cobre (I) (CuAAC). Inicialmente, o método utilizado foi padronizado a partir da síntese do modelo dipeptídeo de treonina (8), cuja ligação peptídica foi substituída pelo grupo 1,2,3-triazol 1,4- dissubstituído (NHFmoc-Thr-(ciclo 1,2,3-triazol 1,4 dissubstituído)-Thr-OH). A estratégia via CuAAC conduziu à obtenção do dipeptídeo modificado em excelente rendimento (98%) e permitiu estabelecer as condições a serem empregadas na obtenção do peptídeo mais complexo de cadeia longa 1. A reação de CuAAC gerou o peptídeo 1 com rendimento bruto satisfatório (70%). A obtenção de 1 foi confirmada pela análise de Ressonância Magnética Nuclear de próton (RMN 1H), a qual permitiu identificar a presença do grupo 1,2,3-triazol 1,4-dissubstituído. Adicionalmente, análises posteriores por espectrometria de massas (ESI-MS) sugerem a obtenção do peptídeo 1. / Peptides are biomolecules which present great structural and functional variety, acting in several biological processes. These molecules are widely used in therapeutics, and recently represent a very promising field for development of novel drugs, specially on synthetic vaccines. Scientific advances related to identification techniques, analysis and purification stimulate researches in attempt to produce peptides-based drugs, which can be extracted from natural sources or chemically synthesized (in liquid or solid phase), enzymatic process or both (semi-synthesis) and recombinant DNA technology. However, due to limitations concerning natural peptides, such as, proteolytic liability, toxicity and low bioavailability, becomes necessary the synthesis of modified peptides. Being biological function of a peptide defined by its structural conformation, adding a modification in a peptide structure must be able to maintain or stabilize it. The development of novel and efficient synthetic route of modified peptides is necessary to overcome the limitations related to proteolytic liability, toxicity and low bioavailability, to contribute with novel therapeutic strategies, mostly development of vaccines. So, adding a 1,2,3-triazole group can afford desirable chemical-physical properties in drug discovery. The objective was develop a method to synthesize peptides containing 1,4-disubstituted 1,2,3-triazole group, such as peptide 1, which is constituted by sixteen threonine residues and one 1,4 disubstituted 1,2,3-triazole group (NH2-(Thr)7-Thr-(1,4- disubstituted 1,2,3-triazole cycle)-Thr-(Thr)7-OH). Moreover, due to the similarity with T. cruzi mucins that present great composition of threonine, 1 can be employed in development of vaccines related to infectious processes caused by T. cruzi. The preparation of 1 envolved an association between the solid-phase synthesis of peptide and reactions of copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). Initially, the method was standardized from synthesis of threonine dipeptide (8), whose peptide bond was replaced by 1,4-disubstituted 1,2,3-triazole group (NHFmoc-Thr-(1,4-disubstituted 1,2,3-triazole cycle)-Thr-OH). The strategy via CuAAC gave the modified dipeptide in good yield (98%) and allowed to establish the conditions to prepare the more complex peptide with long chain 1. The CuAAC reaction gave the peptide 1 with good yield (70%). Compound 1 was confirmed by NMR proton analysis which showed the presence of 1,4-disubstituted 1,2,3-triazole group. Additionally, further analysis of mass spectrometry (ESI-MS) suggest the achievement of peptide 1.

Ce manuscrit décrit la synthèse et l’étude physico-chimique de tensioactifs innovants utilisés comme outils biochimiques pour le maintien et la cristallisation de protéines membranaires en solution aqueuse. Un premier chapitre présente les moyens techniques actuels à disposition pour la manipulation et l’étude des protéines membranaires ainsi que les problèmes rencontrés concernant leur inactivation et les alternatives actuelles. Une seconde partie décrit la synthèse d’un lipide hémifluoré possédant un ligand métallique spécifique, qui a été utilisé pour la formation d’un film de Langmuir. Les propriétés du film lipidique (stabilité et fluidité) ont été étudiées et des essais de cristallisation 2D suivant le concept interfacial ont été réalisés sur une protéine recombinante SUR1 « his tag » solubilisée dans des micelles de détergents hydrocarbonés. Le troisième chapitre aborde la notion d’amphiphilie faciale et décrit la synthèse de tensioactifs glucosidiques par « click chemistry » basés sur corps aromatique central. La persubsitution sélective de têtes hydrophiles sur les positions 1,3,5 et de parties hydrophobes sur les positions 2,4,6 apporte une amphiphilie aux molécules via une ségrégation faciale. Enfin, le dernier chapitre est dédié à l’étude du comportement et des propriétés physico-chimiques des tripodes amphiphiles faciaux en solution aqueuse grâce à différentes techniques : tensiométrie, diffusion de la lumière, CPLH,... / This thesis deals with the synthesis and the physico-chemical study of new surfactants used as tools for holding membrane proteins in aqueous media. A first part presents the existing methods that allow the manipulation of the membrane proteins and describes the current issues encountered which lead to its denaturation. In a second chapter, the synthesis of a hemifluorinated lipid with a specific ligand is presented in order to form a film of Langmuir. The stability and fluidity of the monolayer lipid is monitored and used in experiments of cristallisation 2D following the interfacial concept on the recombinant membrane protein SUR1 « his tag » keep soluble in water with hydrocarbonated detergents. The third part defines the term associated to facial amphiphile and presents a synthesis by « click chemistry » of glucosidic surfactants with an aromatic core persubstitued. The alternated and selective substitution on 1,3,5 and 2,4,6 positions of the aromatic ring by respectively hydrophilic heads and hydrophobic tails induces a facial segregation. The last chapter concerns the study of facial amphiphiles behavior and its physico-chemical properties in aqueous solution by using several methods : tensiometry, dynamic diffusion light scattering, HPLC,...

[pt] A importância terapêutica dos compostos contendo 1,2,3-triazóis deve-se ao seu espectro de atuação farmacológica, entre as quais podemos destacar a ação anticâncer, antiviral, antibacteriana, antifúngica, anticonvulsivante entre outras. A facilidade sintética de obtenção de 1,2,3- triazóis por meio da reação de cicloadição 1,3 –dipolar catalisada por cobre (CuAAc), também denominada click chemistry, bem como a reação de cicloadição térmica 1,3-dipolar, torna este grupo bastante atraente como um grupo farmacofórico. O presente trabalho tem como objetivo geral o planejamento, síntese e avaliação de fenil(1-fenil-1H-1,2,3-triazóis-4-il)metanol, também denominados hidróxi-1,2,3-triazóis, visando analisar suas ações farmacológicas frente a leishmaniose. Duas estratégias foram desenvolvidas para a obtenção destes compostos: (i) reação de cicloadição 1,3-dipolar catalisada por cobre (CuAAC) entre 1-fenil-3-(trimetilsilil)prop-2-in-1-óis e aril azidas substituídas previamente preparadas levando assim a obtenção dos fenil(1-fenil-1H-1,2,3-triazóis-4-il)metanol com rendimentos entre 20 e 30 por cento. As aril azidas foram preparadas à partir das anilinas em 60 a 85 por cento de rendimentos e os 1-fenil-3-(trimetilsilil)prop-2-in-1-óis foram preparados à partir da adição de etiniltrimetilsilano aos benzaldeídos comerciais (ii) reação de cicloadição térmica entre aril azidas e (E)-3-(dimetilamino)-1-fenilprop-2-en-1-ona - previamente preparadas à partir de 4-bromoacetofenonas, em rendimentos de 40-50 por cento, seguida de redução dos fenil(1-fenil-1H-1,2,3-triazóis-4-il)metanona com rendimentos variando entre 35-50 por cento levando assim a obtenção dos fenil(1-fenil-1H-1,2,3-triazóis-4-il)metanóis com rendimentos entre 20 e 30 por cento. Os compostos sintetizados foram caracterizados por técnicas de espectroscopia de ressonância magnética nuclear (RMN), infravermelho (IV) e espectrometria de massas (CG-MS). / [en] The therapeutic importance of compounds containing 1,2,3-triazoles is due to their spectrum of pharmacological activity, among which we can highlight the anticancer, antiviral, antibacterial, antifungal, anticonvulsant action, among others. The synthetic facility to obtain 1,2,3-triazoles through the 1,3-dipolar copper-catalyzed cycloaddition reaction (CuAAc), also called click chemistry, as well as the 1,3-dipolar thermal cycloaddition reaction, makes this group quite attractive as a pharmacophoric group. The present work has a general objective the planning, synthesis and evaluation of phenyl (1-phenyl-1H-1,2,3-triazoles-4-yl) methanol, also called hydroxy-1,2,3-triazoles, aiming to analyze their pharmacological actions against leishmaniasis. Two strategies were developed to obtain these compounds: (i) 1,3-dipolar copper-catalyzed cycloaddition reaction (CuAAC) between 1-phenyl-3- (trimethylsilyl) prop-2-in-1-ois and aryl azides substituted previously prepared thus leading to obtaining phenyl (1-phenyl-1H-1,2,3-triazoles-4-yl) methanol with yields between 20 and 30 percent. Aryl azides (50a-i) were prepared from anilines in 60 to 85 percent yields and 1-phenyl-3- (trimethylsilyl) prop-2-in-1-ois were prepared from the addition of ethinyltrimethylsilane to commercial benzaldehydes (ii) thermal cycloaddition reaction between aryl azides and (E) -3- (dimethylamino) -1-phenylprop- 2-en-1-one - previously prepared from 4-bromoacetophenones, in yields of 40-50 percent, followed by reduction of phenyl (1-phenyl-1H-1,2,3-triazoles-4- il) methanone with yields varying between 35-50 percent thus leading to the obtaining of phenyl (1-phenyl-1H-1,2,3-triazoles-4-yl) methanols with yields between 20 and 30 percent. The synthesized compounds were characterized by nuclear magnetic resonance (NMR), infrared (IR) and mass spectrometry (CG-MS) techniques.

In the everlasting battle against cancer the development of drugs targeting new therapeutic pathways is of crucial importance. In the attempt to develop new anticancer agents we have synthesized a library of anthraquinone compounds that show selectivity against leukemia. Mechanistic evaluation of the lead compound reveal that this class of compounds achieve their effects through inhibition of MDM2-MDM4 heterodimer and upregulation of the tumor suppressor p53. Computer aided rational design resulted in the development of a number of compounds with activities in the nanomolar range against various cancer cells. Analysis of the physicochemical properties of selected compounds allowed for their evaluation as potential drug candidates. The successful development of non-toxic formulations permits for the further in vivo investigation of the compounds. Click reactions have found wide spread applications in sensing, materials chemistry, bioconjugation, and biolabeling. A number of very useful click reactions have been discovered, which allow for various applications. In bioconjugation applications, the ability to conduct a secondary conjugation will be very useful in, e.g., protein pull down and binding site identification. Along this line, we describe a neighboring group-assisted facile condensation between an aldehyde and a vicinal aminothiol moiety, leading to the formation of benzothiazoles. The conversion is completed within 5 minutes at low micromolar concentrations at ambient temperature. The facile reaction was attributed to the presence of a neighboring boronic acid, which functions as an intramolecular Lewis Acid in catalyzing the reaction. The boronic acid group is compatible with most functional groups in biomolecules and yet can also be used for further functionalization via a large number of well-known coupling reactions.

Thesis (MSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Cancer is the leading cause of death on the planet, killing an estimated 8.2 million people in the year of 2012.The disease is associated with two families of genes, namely oncogenes and tumour suppressor genes. The hallmarks of cancer pathogenesis include gene amplification, point mutations or chromosomal rearrangements within these genes. Kinases are responsible for the reversible phosphorylation of proteins, which plays a significant and extensive role in cellular signal transduction. Aberrant kinase activity provokes overexpression, mutations and chromosomal translocation and results in the onset of onco- and tumorogenesis, ultimately leading to cancer. Inactivation of this class of enzyme is thus critical as it would result in the suppression of these unwanted activities. For this, researchers have developed kinase inhibitors, specifically targeting these proteins and thus inhibiting signal transduction pathways and tumour growth. This has resulted in great successes, particularly in the case of the commercial inhibitor, imatinib. However, resistance to approved therapeutic agents through mutations has resulted in the search for more potent and selective inhibitors to overcome these obstacles. This project involved the synthesis of bioactive heterocycles linked to 1,2,3-triazoles using either a C-C or C-N bond forming strategy. The synthetic methodology followed included the use of Sonogashira coupling reactions between3-bromoquinoline, 7-chloro-4-iodoquinoline, 4-bromoisoquinolineand5-bromoisoquinolineand trimethylsilylacetylene (TMSA), followed by deprotection of the TMS group to yield heterocycles bearing terminal alkynes. The synthesis of both benzyl azide and 2-(azidomethyl)pyridine as azide fragments, allowed for subsequent coupling of the synthesized azide and alkyne fragments through copper-mediated click chemistry, affording a library of 1,4-substituted 1,2,3-triazole based reversible kinase inhibitors. Synthesis of a second library of o-, m- and p-substituted nitro benzyl azides, allowed for both copper- and ruthenium-mediated click reactions, between the alkynes and nitro benzyl azides synthesized, to yield 1,4- and 1,5-substituted 1,2,3-triazoles, respectively. Finally, reduction of the incorporated o-, m- and p- substituted nitro group, and acylation of the resultant amine with acryloyl chloride, resulted in the incorporation of the important Michael acceptor moiety required for irreversible inhibition. This afforded a library of both reversible and potential irreversible triazole-based kinase inhibitors through efficient copper- and ruthenium-mediated click chemistry. Biological screening and activity assays against the wildtype, and two mutated forms of the EGFR kinase, were undertaken with these synthesized compounds.A number of synthesized inhibitors showed good selectivity for the mutated forms of the EGFR kinase only.The most potent inhibitor N-{2-{[4-(isoquinolin-4-yl)-1H-1,2,3-triazol-1-yl]methyl}phenyl}acrylamide,displayed efficacy in the low μM range - comparable to that of the FDA approved drug, gefitinib. The synthetic methodology derived in this project could be applied to the use of biological space probes with further investigatory research. Furthermore, from the biological screening results obtained, and the selectivity profile shown by these inhibitors, the synthesis of a second generation library of compounds is an additional research possibility. / AFRIKAANSE OPSOMMING: Kanker is die hoof oorsaak van sterftes ter wêreld, wat verantwoordelik is vir die dood van ongeveer 8.2 miljoen mense in die jaar 2012. Die siekte word geassosieer met twee geenfamilies, naamlik onkogene en gewasonderdrukkingsgene. Die kenmerke van kanker pathiogene behels geenversterking, puntmutasies of chromosomale herrangskikking binne in die gene. Kinase is verantwoordelik vir die omkeerbare fosforilering van proteine wat 'n uiters belangrike rol in sellulere sein transduksie speel. Abnormale kinase aktiwiteit lei tot ooruitdrukking, mutasies en chromosomale translokasie wat tot die ontwikkeling van onko- en gewasgroei en wat eindelik tot kanker lei. Deaktivering van die klas van ensieme is dus krities want dit sal die ongewenste abnormale aktiwiteite onderdruk. As gevolg van die bogenoemde, het navorsers kinase inhibeerders ontwikkel wat die spesifieke protein teiken en hiermee die sein transduksie roete asook gewas groei inhibeer. Hiermee het die sukses van inhibeerders veral die kommersiele inhibeerder, imatinib, grootliks toegeneem. Oor die afgelope jare het die belangstelling in die ontwikkeling van meer selektiewe en kragtige inhibeerders toegeneem as gevolg van die weerstand wat goedgekeurde terapeutiese middels opbou. In hierdie projek is daar gebruik gemaak van 'n C-C of C-N bindingsvorming strategie om bioaktiewe heterosikliese molekules te sintetiseer wat gekoppel is aan 1,2,3-triasool funksionele groepe. Die sintetiese metode maak gebruik van Sonogashira reaksies vir die 3-bromo-kwinolien, 7-chloro-4-iodokwinolien, 4-bromoisokwinolien en 5-bromoisokwinolien met trimetielsilielasetileen (TMSA), gevolg met die ontskerming van die TMS-groep om die terminale alkyn op die heterosiklusse te ontbloot. Die asied fragmente, bensiel asied en 2-(asidometiel)piridien, was toe gesintetiseer om met die gevormde heterosiklus alkyne 'n koper ondersteunende kliek chemie te ondergaan. 'n Reeks van 1,4-digesubstitueerde 1,2,3-triasool gebaseerde omkeerbare kinase inhibitore is toe gevorm. 'n Tweede reeks met o-, m-, en p- gesubtitueerde nitro bensiel asiede was gesintetiseer om 1,4- en 1,5- digesubtitueerde 1,2,3-triasole te sintetiseer met behulp van koper- en ruthenium ondersteunende kliek chemie. Laastens was die o-, m-, en p- nitro groepe gereduseer om 'n primêre amien te vorm. Die gevormende amien het 'n asileringsreaksie met akriloïel chloried ondergaan om die kern, die Michael akseptor, te inkorporeer. Die Michael akseptor word benodig om 'n onomkeerbare inhibitoriese aktiwiteit te kan uitvoer. Die projek het dus met behulp van kliek chemie, twee 1,2,3-triasool reekse gelewer wat omkeerbare en onomkeerbare inhibitoriese aktiwiteit kan uitvoer. Die verbindings gesintetiseerd in hierdie projek het keuringstoetse ondergaan teen die wilde tipe en teen twee gemuteerde forme van die EGFR kinase ensiem. Van hierdie verbindings het goeie selektiwiteit vertoon teenoor die gemuteerde EGFR kinase ensiem. Die mees aktiewe inhibeerder, N-{2-{[4-isokwinolin-4-iel)-1H-1,2,3-triasool-1-iel]feniel}akrielamied, het aktiwiteit in die lae μM reeks vertoon. Dié inhibisie waarde is vergelykbaar met die FDA goedgekeurde medikasie, gefitinib. In hierdie projek is sintetiese metodes ontwikkel wat toegepas kan word op meer intensiewe biologiese ondersoeke en asook meer navorsing. Die resultate vekry van die biologiese aktiwiteit, asook die verbindings se selektiwiteit, gee die moontlikheid vir die ontwikkeling en sintese van 'n tweede generasie verbindings.

Glycans are macromolecules that contain several classes. Glycans can play an important role in biological activities. Studying the cell surface glycans can provide a very powerful way to understand the fundamental process. Also it could help to regulate expected cell response. Thus it is very necessary to have a method to detect cell- surface glycans efficiently. An efficient method for glycan detection is necessary. Metabolic glycan labeling and chemoenzymatic glycan labeling are most commonly used. Chemoenzymatic glycan labeling is a rapid and sensitive method which also has high specificity. This method can be applied in both vitro and vivo. However the availability of unnatural sugar nucleotides functioned by bioorthogonal groups is the main limitation for chemoenzymatic labeling. In this thesis, UDP-GlcNAc and UDP-GalNAc derivatives were prepared for further chemoenzymatic labeling by using chemoenzymatic synthesis method.

Depuis quelques années on assiste au développement de nouveaux bio-catalyseurs qui sont des hybrides combinant les avantages de la catalyse organométallique (système robustes, efficaces, mais couteux) à ceux de la catalyse enzymatique (écologique, spécifique mais peu flexible). Parmi les différentes stratégies mises en œuvre pour créer des enzymes artificielles, aucune d'elles n'a jusqu'à présent véritablement envisagé d'utiliser l'activité d'une enzyme et de la combiner à celle d'un composé organique. C'est la nouvelle approche proposée dans ce travail pour tenter d'orienter l'activité catalytique d'une oxydase à fort potentiel industriel, la laccase. Les produits d'oxydation de la laccase sont des radicaux phénoxyls qui se recombinent dans le milieu sans contrôle de l'enzyme. Chez certaines plantes, des petites protéines nommées « dirigent proteins » interagissent avec les radicaux phénoxyls pour conduire à la formation d'un seul produit optiquement pur. Dans ce travail, nous avons tenté de mimer ces « dirigent proteins » en greffant une molécule cage de type cyclodextrine à proximité du site actif de la laccase. Dans un premier temps, nous avons réalisé la synthèse de modules organiques dits « plateformes » possédants a) un point d'attachement à l'enzyme, b) un groupement pour la purification des protéines fonctionnalisées et c) une cyclodextrine qui permet d'encapsuler un grand nombre de molécules organiques. Par des mesures de fluorescences et d'immuno-détection, nous avons identifié les conditions optimales de fonctionnalisation pour la laccase et ainsi validé sa dérivatisation. / In recent years we are witnessing the development of new bio-catalysts which are hybrids combining the advantages of organometallic catalysis (robust and efficient system, but expensive) to those of enzymatic catalysis (ecological, specific but not very flexible). Among the various strategies used to create artificial enzymes, none of them has yet seriously considered to combine an enzyme activity with that of an organic compound. This is the new approach proposed in this work to try to orient the catalytic activity of the laccase, an oxidase with an industrial potential. The oxidation products of the laccase are phénoxy radicals which recombine in the medium regardless of the activity of the enzyme. In some plants, small proteins called "dirigent proteins" interact with phénoxy radicals leading to the formation of a single optically pure product. In this work, we tried to mimic the "dirigent proteins" by grafting a cyclodextrin-cage molecule near the active site of the laccase. As a first step, we performed the synthesis of organic modules called "platforms" with a) an anchor point to the enzyme, b) a group for functionalized protein purification c) a cyclodextrin that encapsulates a large number of organic molecules. By fluorescence and immunodetection measurements, we identified the optimal conditions for laccase functionalization and thus validated its derivatization. Monitoring the oxidation of coniferyl alcohol by the functionalized laccase with a cyclodextrined platform highlights a change in the kinetic profiles of the substrate and products. This difference appears due to the location of the cyclodextrin near the substrate oxidation site.