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Nous nous sommes intéressés au TMC-95A, un tripeptide cyclique naturel inhibant le protéasome humain d’une façon non-covalente à des concentrations de l’ordre du nanomolaire. Nous avons montré que des mimes linéaires du TMC-95A contenant un motif 3-hydroxyoxindolyl alanine conservent l’activité inhibitrice de ce dernier. Mon travail a porté sur la synthèse d’une bibliothèque de mimes linéaires du TMC-95A en partant des amino-acides protéogéniques et des dérivés de la 3-hydroxyoxindolyl alanine. Nous avons préparé des bras espaceurs hydrosolubles contenant des motifs éthylène glycol que nous avons couplés avec les têtes inhibitrices pour l’élaboration de nouveaux inhibiteurs bivalents capables de cibler simultanément deux des six sites catalytiques du protéasome constitutif et de l’immunoprotéasome.Au cours de la synthèse de la 3-hydroxyoxindolyl alanine, il a été observé qu’en milieu basique, ce résidu C-protégé se transpose lentement et d'une façon peu décrite dans la littérature en γ-lactame. Nous avons généralisé cette réaction à la synthèse de lactames de 5 à 12 chaînons par isomérisation d’oxindoles substitués en N-1 par un groupement électroattracteur et en C-3 par une chaine ω-aminée de longueur variable. Ces oxindoles ayant une chaîne aminée ont été obtenus à partir de deux familles différentes : des composés nitrés et des dérivés N-Boc protégés. L’aptitude des différentes molécules synthétisées à inhiber le protéasome et l’immunoprotéasome a été étudiée. / Nous nous sommes intéressés au TMC-95A, un tripeptide cyclique naturel inhibant le protéasome humain d'une façon non-covalente à des concentrations de l'ordre du nanomolaire. Nous avons montré que des mimes linéaires du TMC-95A contenant un motif 3-hydroxyoxindolyl alanine conservent l'activité inhibitrice de ce dernier. Mon travail a porté sur la synthèse d'une bibliothèque de mimes linéaires du TMC-95A en partant des amino-acides protéogéniques et des dérivés de la 3-hydroxyoxindolyl alanine. Nous avons préparé des bras espaceurs hydrosolubles contenant des motifs éthylène glycol que nous avons couplés avec les têtes inhibitrices pour l'élaboration de nouveaux inhibiteurs bivalents capables de cibler simultanément deux des six sites catalytiques du protéasome constitutif et de l'immunoprotéasome. Au cours de la synthèse de la 3-hydroxyoxindolyl alanine, il a été observé qu'en milieu basique, ce résidu C-protégé se transpose lentement et d'une façon peu décrite dans la littérature en γ-lactame. Nous avons généralisé cette réaction à la synthèse de lactames de 5 à 12 chaînons par isomérisation d'oxindoles substitués en N-1 par un groupement électroattracteur et en C-3 par une chaine ω-aminée de longueur variable. Ces oxindoles ayant une chaîne aminée ont été obtenus à partir de deux familles différentes : des composés nitrés et des dérivés N-Boc protégés. L'aptitude des différentes molécules synthétisées à inhiber le protéasome et l'immunoprotéasome a été étudiée.

Le projet scientifique a consisté au développement de nouveaux processus domino ayant pour étape clé la fonctionnalisation d’une liaison C-H. L’introduction de cette étape de fonctionnalisation C-H a permis d’améliorer significativement l’efficacité moyenne de la réaction et a offert de nouvelles perspectives du point de vue synthétique. Ainsi, nous avons exploité des stratégies se basant sur des séquences Heck / fonctionnalisation C-H, des réactions de difonctionnalisation d’alcènes en conditions oxydantes et un processus d'aminopalladation / fonctionnalisation C-H. Ces méthodologies nous ont permis un accès rapide aux motifs spiroquinolinones, spirooxindoles, oxindoles disubstitués en position 3, oxindoles tétracycliques et pyrrolo[1,2-a]indoles. / The projet consists in developing new domino processes involving C-H functionalization as the key steps. The introduction of C-H functionalization in the domino reaction leads to the enhancing significantly the efficiency of the reaction and offers new perspectives in a synthetic point of view. In this context, we have exploited different strategies basing on Heck/C-H functionalization process, difunctinalization of alkenes reactions through oxidative addition and a sequencial intramolecular aminopalladation/C-H functionalization. These methodologies allow rapid constructions of spiroquinolines, spirooxindoles, 3,3'-disubstituted oxindoles, tetracyclic oxindoles and pyrrolo[1,2-a]indoles cores.

This thesis describes the investigation of thiadiazolidine 1-oxides and structurally related compounds as ligands in palladium catalysis. The introduction will provide background information on subjects related to the work of the main project. Palladium catalysed cross couplings, namely the Heck and Tsuji-Trost reactions, will feature prominently and will be discussed in basic detail. A general outline of different classes of ligands used in palladium catalysis will also be put forward. Extraneous factors which affect catalyst reactivity will also be discussed, including the use of microwave irradiation and the effect of additives. Special attention is paid towards sulfur containing ligands. As their use has been relatively limited this will also include other areas of catalysis. Investigations into the synthesis of esermethole prompt a general background of methods of synthesising oxindoles and also examples of previous syntheses of the compound. The second chapter begins by describing the initial exploratory work, the testing of a thiadiazolidine 1-oxide compound as a ligand for the Heck reaction. Aryl iodides are successfully coupled to a range of styrenes and α,β-unsaturated esters in excellent yields under microwave conditions. Aryl bromides are also successfully coupled after some optimisation. In many cases the presence of tetrabutylammonium bromide is required to prevent shattering of the sealed microwave vial. A range of differently substituted thiadiazolidine 1-oxides were synthesised in order to establish a pattern of reactivity based on steric and electronic factors. Structurally related chiral compounds were also synthesised, including the first reported enantiomerically pure thiadiazol-3-one 1-oxide and thiatriaza-indene 3-oxide systems chiral at the sulfur atom. The synthesis of oxindoles using palladium mediated and non-catalytic chemistry was also investigated. Investigations into the synthesis of esermethole were undertaken; the key stereoinducing reaction, the decarboxylative asymmetric allyic alkylation reaction, achieved a 46% ee. A formal synthesis of esermethole was outlined in 8 steps from commercially available material. The third chapter is the experimental section and is dedicated to the methods of synthesis and characterization of the compounds mentioned in the previous chapter. X-ray reports regarding the crystallographic representation of the structures presented in chapter two are provided in appendix A.

In the present study, we designed a new chemical template that contains an oxindole moiety as potential dual-pathway inhibitors of the Raf/MEK/ERK and PI3K/Akt signaling pathways. The design hypothesis is to evaluate whether the oxindole ring system will approximately orient functional groups in a similar manner to the thiazolidinedione moiety, and thus maintain biological activity as dual-pathway inhibitors of the Raf/MEK/ERK and PI3K/Akt signaling pathways. Furthermore, the oxindole ring will provide the flexibility to allow the introduction of various substituents on the oxindole moiety, thereby facilitating comprehensive SAR studies to further explore the biological activity.

Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularmente conhecida como cat’s claw ou “unha-de-gato”, é uma liana encontrada principalmente na região Amazônica assim como Uncaria guianensis (Aubl.) Gmel. (Rubiaceae), que é utilizada como substituinte ou adulterante em relação a U. tomentosa devido à sua maior abundância e menor valor comercial. A diferenciação de ambas pode ser realizada com base em aspectos morfoanatômicos, mas limita-se à composição química em derivados, como extratos fluidos e secos. As cascas do caule de U. tomentosa são compostas majoritariamente por derivados triterpênicos, polifenóis e alcaloides oxindólicos, aos quais são atribuídas as principais atividades biológicas da espécie. Contudo, o perfil de alcaloides oxindólicos é variável devido à ocorrência de quimiotipos e a elevada susceptibilidade dos mesmos à isomerização. Assim, a presente tese teve como objetivo avaliar a relevância dos alcaloides oxindólicos em U. tomentosa no que tange ao reconhecimento de adulteração na espécie, ocorrência de quimiotipos e isomerização desses compostos. Para isso, foram construídos modelos de classificação e regressão multivariada a partir das análises de CLAE-PDA, IV e UV destinados a diferenciação entre U. tomentosa e U. guianensis e ao reconhecimento de adulteração e determinação do percentual de adulterante em amostras de U. tomentosa. Os resultados obtidos demonstraram que os critérios farmacopéicos atualmente utilizados no controle de qualidade da matéria-prima vegetal e derivados de U. tomentosa baseados nos alcaloides oxindólicos são inefetivos em relação ao reconhecimento de adulteração. (Continuação A avaliação da atividade citotóxica dos diferentes quimiotipos baseados no perfil de alcaloides oxindólicos em U. tomentosa frente a leucócitos humanos e as células tumorias de bexiga (T24) e glioblastoma (U-251-MG) humanos, demonstrou que a seletividade frente às células tumorais é depentente do quimiotipo. Adicionalmente, a complexação dos alcaloides oxindólicos com sulfobutil-éter-β-ciclodextrina (SBE-βCD) minimizou a velocidade de isomerização sob condições de incubação (pH = 7,4; 37 ºC), sem contudo inibir o processo de isomerização. / Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularly known as cat’s claw, is a liana found mainly in the Amazon rainforest as well as Uncaria guianensis (Aubl.) Gmel. (Rubiaceae) used as substituent or adulterant due to their higher wild population and lower market value. The differentiation among the raw material of both species can be performed from morphological and microscopic characteristics, but is limited in derivatives such as fluid and freeze-dried extracts. The stem bark from U. tomentosa is composed mainly by quinovic acid glycosides, polyphenols and oxindole alkaloids, to which have been assigned the major biological activities of the specie. However, the oxindole alkaloids profile in the U. tomentosa is variable due to chemotype occurrence and their susceptibility to isomerization. Thus, this study aimed to evaluate the relevance of oxindole alkaloids at U. tomentosa in relation to adulteration recognition, chemotype occurrence and oxindole alkaloids isomerization. Classification and multivariate regression models were built from HPLC-PDA, FT-IR and UV data to differentation between U. tomentosa e U. guianensis, as well as for adulteration recognition and determination of the adulterant level in the U. tomentosa. The current U.S. pharmacopeia monographs specifications for quality control of stem bark raw material from U. tomentosa, as well as for their derivatives, such as powdered dried extract, based on the oxindole alkaloids were ineffective for adulteration recognition. The cytotoxic activity evaluation of the different chemotypes, based on the oxindole alkaloid profile, against the human leukocytes and against human bladder cancer cell line (T24) and human glioblastoma cell line (U-251-MG) demonstrated that selectivity against the tumoral cells is dependent of the chemotype. In addition, the complexation of the oxindole alkaloids with Sulfobutyl ether β-cyclodextrin (SBE-βCD) minimize the isomerization rate under incubation conditions (pH = 7.4; 37 ºC) but without, however, inhibit the isomerization process.

Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularmente conhecida como cat’s claw ou “unha-de-gato”, é uma liana encontrada principalmente na região Amazônica assim como Uncaria guianensis (Aubl.) Gmel. (Rubiaceae), que é utilizada como substituinte ou adulterante em relação a U. tomentosa devido à sua maior abundância e menor valor comercial. A diferenciação de ambas pode ser realizada com base em aspectos morfoanatômicos, mas limita-se à composição química em derivados, como extratos fluidos e secos. As cascas do caule de U. tomentosa são compostas majoritariamente por derivados triterpênicos, polifenóis e alcaloides oxindólicos, aos quais são atribuídas as principais atividades biológicas da espécie. Contudo, o perfil de alcaloides oxindólicos é variável devido à ocorrência de quimiotipos e a elevada susceptibilidade dos mesmos à isomerização. Assim, a presente tese teve como objetivo avaliar a relevância dos alcaloides oxindólicos em U. tomentosa no que tange ao reconhecimento de adulteração na espécie, ocorrência de quimiotipos e isomerização desses compostos. Para isso, foram construídos modelos de classificação e regressão multivariada a partir das análises de CLAE-PDA, IV e UV destinados a diferenciação entre U. tomentosa e U. guianensis e ao reconhecimento de adulteração e determinação do percentual de adulterante em amostras de U. tomentosa. Os resultados obtidos demonstraram que os critérios farmacopéicos atualmente utilizados no controle de qualidade da matéria-prima vegetal e derivados de U. tomentosa baseados nos alcaloides oxindólicos são inefetivos em relação ao reconhecimento de adulteração. (Continuação A avaliação da atividade citotóxica dos diferentes quimiotipos baseados no perfil de alcaloides oxindólicos em U. tomentosa frente a leucócitos humanos e as células tumorias de bexiga (T24) e glioblastoma (U-251-MG) humanos, demonstrou que a seletividade frente às células tumorais é depentente do quimiotipo. Adicionalmente, a complexação dos alcaloides oxindólicos com sulfobutil-éter-β-ciclodextrina (SBE-βCD) minimizou a velocidade de isomerização sob condições de incubação (pH = 7,4; 37 ºC), sem contudo inibir o processo de isomerização. / Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularly known as cat’s claw, is a liana found mainly in the Amazon rainforest as well as Uncaria guianensis (Aubl.) Gmel. (Rubiaceae) used as substituent or adulterant due to their higher wild population and lower market value. The differentiation among the raw material of both species can be performed from morphological and microscopic characteristics, but is limited in derivatives such as fluid and freeze-dried extracts. The stem bark from U. tomentosa is composed mainly by quinovic acid glycosides, polyphenols and oxindole alkaloids, to which have been assigned the major biological activities of the specie. However, the oxindole alkaloids profile in the U. tomentosa is variable due to chemotype occurrence and their susceptibility to isomerization. Thus, this study aimed to evaluate the relevance of oxindole alkaloids at U. tomentosa in relation to adulteration recognition, chemotype occurrence and oxindole alkaloids isomerization. Classification and multivariate regression models were built from HPLC-PDA, FT-IR and UV data to differentation between U. tomentosa e U. guianensis, as well as for adulteration recognition and determination of the adulterant level in the U. tomentosa. The current U.S. pharmacopeia monographs specifications for quality control of stem bark raw material from U. tomentosa, as well as for their derivatives, such as powdered dried extract, based on the oxindole alkaloids were ineffective for adulteration recognition. The cytotoxic activity evaluation of the different chemotypes, based on the oxindole alkaloid profile, against the human leukocytes and against human bladder cancer cell line (T24) and human glioblastoma cell line (U-251-MG) demonstrated that selectivity against the tumoral cells is dependent of the chemotype. In addition, the complexation of the oxindole alkaloids with Sulfobutyl ether β-cyclodextrin (SBE-βCD) minimize the isomerization rate under incubation conditions (pH = 7.4; 37 ºC) but without, however, inhibit the isomerization process.

Submitted by Alison Vanceto (alison-vanceto@hotmail.com) on 2016-10-26T10:57:10Z No. of bitstreams: 1 DissGPS.pdf: 9587605 bytes, checksum: d37ce6a94677c8fb0a582d19bf1ad134 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-11T14:02:36Z (GMT) No. of bitstreams: 1 DissGPS.pdf: 9587605 bytes, checksum: d37ce6a94677c8fb0a582d19bf1ad134 (MD5) / Approved for entry into archive by Ronildo Prado (ronisp@ufscar.br) on 2017-04-11T14:02:46Z (GMT) No. of bitstreams: 1 DissGPS.pdf: 9587605 bytes, checksum: d37ce6a94677c8fb0a582d19bf1ad134 (MD5) / Made available in DSpace on 2017-04-11T14:16:58Z (GMT). No. of bitstreams: 1 DissGPS.pdf: 9587605 bytes, checksum: d37ce6a94677c8fb0a582d19bf1ad134 (MD5) Previous issue date: 2016-07-29 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A combined tris(trimethylsilyl)silane and visible-light-promoted intramolecular reductive cyclization protocol for the synthesis of indoles and oxindoles has been developed (Scheme 1).1 This straightforward and efficient protocol shows a broad functional-group tolerance and enables rapid and practical synthesis of functionalized nitrogen-based heterocycles in high/moderate yields under additive and metal-free, mild photochemical conditions. Besides the synthetic developments, the reaction mechanism was also investigated by a set of controlled experiments and UVvisible analyses, as well as kinetic study.2 From these studies, we have concluded that the reaction pathway for this strategy occurs through an Electron Donor-Acceptor (EDA) complex.3 to be continued ... / Uma nova metodologia para síntese de indóis e oxindóis foi desenvolvida através de um processo de ciclização redutiva intramolecular utilizando uma combinação da luz visível e tris(trismetilsilil)silano (Scheme 2).1 Este protocolo sintético mostrou-se eficiente e abrangente a diversos substratos funcionalizados, permitindo assim uma rápida e prática síntese de compostos nitrogenados heterocíclicos com altos/moderados rendimentos diante de uma condição fotoquímica livre de metais, bem como aditivos. Além do desenvolvimento sintético, o mecanismo da reação também foi investigado por uma série de experimentos controlados e estudos e espectroscópicos, bem como estudos cinéticos.2 A partir destes estudos, concluímos que o caminho reacional para esta estratégia ocorre através de um complexo doador-aceptor (EDA).3 continua ...

Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularmente conhecida como cat’s claw ou “unha-de-gato”, é uma liana encontrada principalmente na região Amazônica assim como Uncaria guianensis (Aubl.) Gmel. (Rubiaceae), que é utilizada como substituinte ou adulterante em relação a U. tomentosa devido à sua maior abundância e menor valor comercial. A diferenciação de ambas pode ser realizada com base em aspectos morfoanatômicos, mas limita-se à composição química em derivados, como extratos fluidos e secos. As cascas do caule de U. tomentosa são compostas majoritariamente por derivados triterpênicos, polifenóis e alcaloides oxindólicos, aos quais são atribuídas as principais atividades biológicas da espécie. Contudo, o perfil de alcaloides oxindólicos é variável devido à ocorrência de quimiotipos e a elevada susceptibilidade dos mesmos à isomerização. Assim, a presente tese teve como objetivo avaliar a relevância dos alcaloides oxindólicos em U. tomentosa no que tange ao reconhecimento de adulteração na espécie, ocorrência de quimiotipos e isomerização desses compostos. Para isso, foram construídos modelos de classificação e regressão multivariada a partir das análises de CLAE-PDA, IV e UV destinados a diferenciação entre U. tomentosa e U. guianensis e ao reconhecimento de adulteração e determinação do percentual de adulterante em amostras de U. tomentosa. Os resultados obtidos demonstraram que os critérios farmacopéicos atualmente utilizados no controle de qualidade da matéria-prima vegetal e derivados de U. tomentosa baseados nos alcaloides oxindólicos são inefetivos em relação ao reconhecimento de adulteração. (Continuação A avaliação da atividade citotóxica dos diferentes quimiotipos baseados no perfil de alcaloides oxindólicos em U. tomentosa frente a leucócitos humanos e as células tumorias de bexiga (T24) e glioblastoma (U-251-MG) humanos, demonstrou que a seletividade frente às células tumorais é depentente do quimiotipo. Adicionalmente, a complexação dos alcaloides oxindólicos com sulfobutil-éter-β-ciclodextrina (SBE-βCD) minimizou a velocidade de isomerização sob condições de incubação (pH = 7,4; 37 ºC), sem contudo inibir o processo de isomerização. / Uncaria tomentosa (Willd.) DC. (Rubiaceae), popularly known as cat’s claw, is a liana found mainly in the Amazon rainforest as well as Uncaria guianensis (Aubl.) Gmel. (Rubiaceae) used as substituent or adulterant due to their higher wild population and lower market value. The differentiation among the raw material of both species can be performed from morphological and microscopic characteristics, but is limited in derivatives such as fluid and freeze-dried extracts. The stem bark from U. tomentosa is composed mainly by quinovic acid glycosides, polyphenols and oxindole alkaloids, to which have been assigned the major biological activities of the specie. However, the oxindole alkaloids profile in the U. tomentosa is variable due to chemotype occurrence and their susceptibility to isomerization. Thus, this study aimed to evaluate the relevance of oxindole alkaloids at U. tomentosa in relation to adulteration recognition, chemotype occurrence and oxindole alkaloids isomerization. Classification and multivariate regression models were built from HPLC-PDA, FT-IR and UV data to differentation between U. tomentosa e U. guianensis, as well as for adulteration recognition and determination of the adulterant level in the U. tomentosa. The current U.S. pharmacopeia monographs specifications for quality control of stem bark raw material from U. tomentosa, as well as for their derivatives, such as powdered dried extract, based on the oxindole alkaloids were ineffective for adulteration recognition. The cytotoxic activity evaluation of the different chemotypes, based on the oxindole alkaloid profile, against the human leukocytes and against human bladder cancer cell line (T24) and human glioblastoma cell line (U-251-MG) demonstrated that selectivity against the tumoral cells is dependent of the chemotype. In addition, the complexation of the oxindole alkaloids with Sulfobutyl ether β-cyclodextrin (SBE-βCD) minimize the isomerization rate under incubation conditions (pH = 7.4; 37 ºC) but without, however, inhibit the isomerization process.