Thèse (Ph. D.)--Université Laval, 2007. / Titre de l'écran-titre (visionné le 18 sept. 2007). Bibliogr.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / An efficient method to obtain 2-methyl-5-(methylpropanoate-3-yl)-7-trifluoromethylpyrazolo[1,5-a]pyrimidine 2 from the reaction of compound methyl 7,7,7-trifluoro-4-methoxy-6-oxo-heptenoate with 3-amino-5-methyl-1H-pyrazol. This compound 2 brought to reaction with hydrazine monohydrate to obtain 2-methyl-7-trifluoromethylpyrazolo[1,5-a]pyrimidine-5-propanehydrazine 3 and after were later brought to cyclocondensation reaction with a series of β-alkoxyvinyltrifluoromethyl ketones giving the series of news bi-heterocyclic 5-[(5-(trifluoromethyl)-5-hydroxy- (3-substituted)-4,5-dihydro-1H-pyrazol-1-yl)-1-propan-1-one-3-yl]-2-methyl-7-trifluoro methyl)pyrazolo[1,5-a]pyrimidines compounds 5a-l. Compound 2-methyl-5-(methylpropanoate-3-yl)-7-trifluoromethylpyrazolo[1,5-a]pyrimidine 2 brought to transesterification reaction and hydrolises reaction for obtaining the compounds 6 and 7. The structures of all synthesized compounds were confirmed by 1H, 13C, 19F NMR data, and two-dimensional NMR techniques like HETCOR and COLOC, mass spectrometry data. / Este trabalho descreve um método eficiente para a obtenção de 2-metil-5-(propanoato-3-il de metila)-7-trifluormetilpirazolo[1,5-a]pirimidina 2 a partir da reação de ciclocondensação do composto 7,7,7-trifluor-4-metoxi-6-oxo-4-heptenoato de metila com 3-amino-5-metil-1H-pirazol. Este composto 2 foi levado à reação com monohidrato de hidrazina obtendo-se a 2-metil-7-trifluormetilpirazolo[1,5-a]pirimidina-5-propanohidrazina 3. Posteriormente, o composto 3 foi levado à reação de ciclocondensação do tipo [3+2] com uma série de β-alcoxivniltrifluormetil cetonas alquil e aril substituídas utilizando etanol como solvente, resultando em uma série de compostos bi-heterocíclicos inéditos 5-[(5-trifluormetil)-5-hidróxi-(3-substituidos)-4,5-diidro-1H-pirazol-1-il)-1-propan-1-ona-3-il]-2-metil-7-trifluormetilpirazolo[1,5-a]pirimidina 5a-l. O composto 2-metil-5-(propanoato-3-il de metila)-7-trifluormetilpirazolo[1,5-a]pirimidina 2 foi levado à reação de transesterificação e à reação de hidrólise para a formação dos respectivos compostos 6 e 7. As estruturas de todos os compostos sintetizados foram confirmadas por dados de RMN 1H, 13C, 19F e técnicas de RMN bidimensionais como HETCOR e COLOC, além de dados de espectrometria de massas.

Made available in DSpace on 2016-08-17T18:39:37Z (GMT). No. of bitstreams: 1 3649.pdf: 6160139 bytes, checksum: e2fc962eefef9b03fa83e0311a505531 (MD5) Previous issue date: 2010-11-23 / Financiadora de Estudos e Projetos / In this research molecular docking was used to study enzime-ligand complexes of Cyclooxygenase 1 (COX-1) and Cyclooxygenase 2 (COX-2) with pyrimidine derivatives, aiming at understanding the possible mechanisms of action of these compounds and, thus, suggest modifications that could increase their specificity. The chosen ligands were a series of 25 substituted pyrimidines with known activity. The three-dimensional structures of these compounds were obtained by molecular modeling and that of the enzymes from the PDB and PDBSum under the codes 2OYE and 1CX2 for COX-1 and COX-2 respectively. The binding sites chosen for the docking studies were 20 Å around the crystallographic ligands IM8-700 (2OYE) and SC-558 (1CX2). In the COX-1 formed complexes the SO2Me moiety is positioned in such a way as to form hydrogen bonds with Ile517 and Phe518. The benzo[b]thiophen-2-ylmethyl-[2-(4-methanesulfonylphenyl)-6-trifluoromethylpyrimidin-4- yl]amine formed the most favorable complex with COX-1. In COX-2, the enzyme-ligand interaction pattern shows the SO2Me group in the side pocket, forming hydrogen bonds with His90 and Arg513 and the different substituent groups of the pyrimidine ring form hydrogen bonds with Arg120 and Tyr355. The presence of a small lipophilic pocket in COX-2 and the docking results suggest that the ligands 2, 15, 17, 22 and 23 may have their activity enhanced by the addition of a hydrophobic group on the phenyl or thiophenyl rings so this group can interact within this pocket. In both cases the mechanism of inhibition is probably competitive. As the search for new anti-inflammatory drugs must deal with a subtle balance of COX-2 and COX-1 inhibitions, the ligands 2 and 22 that showed better results for COX-2 rather than for COX-1 would be the most promising ones and therefore, those that should be tested in vivo. / Neste trabalho, o docking molecular foi utilizado para o estudo da formação de complexos alvoligante das enzimas Ciclooxigenase 1 (COX-1) e Ciclooxigenase 2 (COX-2) com derivados pirimidínicos, com a finalidade de entender os possíveis mecanismos de ação e, assim, propor modificações nos compostos visando diminuir prováveis efeitos colaterais. Os ligantes escolhidos foram uma série de 25 pirimidinas substituídas com atividade conhecida. As estruturas tridimensionais destas moléculas foram obtidas por modelagem molecular e as das enzimas dos bancos de dados PDB e PDBSum sob o código 2OYE e 1CX2 para COX-1 e COX- 2 respectivamente. Os sítios de ligação escolhidos para os cálculos de docking foram de 20 Å ao redor dos ligantes cristalográficos IM8-700 (2OYE) e SC-558 (1CX2). Das pirimidinas analisadas as que formaram complexo com a COX-1 se orientaram com a porção SO2Me formando ligações de hidrogênio com a Ile517 e Phe518. Sendo o benzo[b]tiofen-2-ilmetil-2-(4- metanosulfonilfenil)-6-trifluorometilpirimidina-4-il]amina o mais favorável para a formação de complexo com a COX-1. Para a COX-2, os compostos que se ligaram mostram um padrão que inclui ligações de hidrogênio entre a porção SO2Me e a His90 e Arg513 do bolso lateral e entre a Arg120 e Tyr355 com os grupos substituintes do anel pirimidínico. A presença de um pequeno bolso lipofílico na COX-2 e os resultados de docking permitem sugerir que os ligantes 2, 15, 17, 22 e 23 poderiam mostrar melhor atividade mediante a adição de um grupo hidrofóbico no anel fenila ou tiofenila para que este grupo se posicione dentro desse bolso. Em ambos os casos o tipo de inibição provável é o competitivo. Como a busca por novos fármacos antiinflamatórios deve lidar com um equilíbrio entre a inibição de COX-2 e COX-1, os ligantes 2 e 22 que apresentaram resultados favoráveis para a COX-2 e não tanto para a COX-1 seriam os mais promissores e, portanto, aqueles que poderiam ser testados in vivo.

A dor neuropática atinge cerca de 6 a 10% da população global e estima-se o seu aumento nos próximos anos. Essa síndrome não tem cura e afeta consideravelmente a qualidade de vida das pessoas por ela acometidas. Os medicamentos utilizados atualmente para o seu tratamento, como antidepressivos, anticonvulsivantes, opióides, dentre outros, não proporcionam um resultado satisfatório pelo fato de não reduzirem consideravelmente os sintomas e/ou por terem muitos efeitos colaterais. Pesquisas recentes mostram que o receptor sigma-1 pode ser utilizado no tratamento da dor neuropática. Verificou-se na literatura uma nova série de pirimidinas que são capazes de se ligar ao receptor sigma-1, atuando como seus antagonistas, sendo potenciais alvos para a produção de fármacos que podem ser utilizados no tratamento da dor neuropática. Então, estudos de Relações Quantitativas Estrutura-Atividade (QSAR) foram realizados utilizando os métodos de Mínimos Quadrados Parciais (PLS) e Redes Neurais Artificiais (ANN) para prever a atividade biológica dessa série de pirimidinas. Os resultados obtidos se mostraram satisfatórios tanto para o método de PLS (r2 = 0,877, q2 = 0,800 e r2teste = 0,738), quanto para o método de ANN (r2trein = 0,734, r2val = 0,753 e r2teste = 0,676), mostrando que o conjunto de compostos antagonistas do receptor Sigma-1 pode ser descrito tanto de forma linear quanto de forma não-linear. / Neuropathic pain affects about 6 to 10% of the global population and it is estimated to increase in the coming years. This syndrome has no cure and considerably affects the life quality of people affected by it. Medications currently used for its treatment, such as antidepressants, anticonvulsants, opioids, among others, do not provide a satisfactory result because they do not significantly reduce the symptoms and/or have many side effects. Recent research shows that the sigma-1 receptor can be used in the treatment of the neuropathic pain. A new series of pyrimidines have been found in the literature, which are capable of binding to the sigma-1 receptor, acting as its antagonists, and have been synthesized as potential targets that can be used in the treatment of the neuropathic pain. Therefore, Quantitative Structure-Activity Relationships (QSAR) were performed using Partial Least Squares (PLS) and Artificial Neural Networks (ANN) methods to predict the biological activity of this series of pyrimidines. Through the mathematical models obtained by PLS (r2 = 0.877, q2 = 0.800 and r2test = 0.738) and ANN (r2trein = 0.734, r2val = 0.753 and r2test = 0.676) methods, it was showed that they were able to predict the biological activity of the studied pyrimidines.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The synthetic routes to three types of phosphate prodrugs of 6-hetaryl-7-deazapurine ribonucleosides based on palladium-catalyzed cross-coupling reactions have been developed. CycloSal- and phosphoramidate pronucleotides and octadecyl phosphates derived from 6- hetaryl-7-deazapurine ribonucleosides were screened for their in vitro cytostatic activity. It was shown that cytostatic activity of cycloSal phosphates was similar or slightly lower compared to the parent nucleosides. Significant drop of cytostatic activity was observed in phosphoramidate pronucleotides. Octadecyl phosphates were devoid of any cytostatic activity. 6-Hetaryl-7-deazapurine ribonucleosides with bulky groups in position 6 showed very strong and selective inhibition of adenosine kinase from Mycobacterium tuberculosis. 2'-Modified 6-hetaryl-7-deazapurine nucleosides: 2'-O-methylribonucleosides, arabinonucleosides and 2'- deoxy-2'-fluororibonucleosides, were prepared by multistep functional group transformations from a ribonucleoside. The synthesis of 2'-deoxy-2',2'-difluoro-erythro-pentofuranosyl nucleosides was based on a glycosylation of 6-chloro-7-deazapurine with a sugar synthon followed by palladium-catalyzed cross-coupling reaction and deprotection. Despite the low yields and laborious separation of the anomers,...

The synthesis of a series of 2-chloropyrimidine derivatives is described. The synthesis began with a nucleophilic addition of lithiated heterocyclic molecules to the 4 position of 2-chloropyrimidine to give dihydropyrimidine intermediates. The intermediates were oxidized to the pyrimidine ring using the DDQ method. This was followed by an addition-elimination reaction of an amine to the 2-chloropyrimidine derivative. The structure and properties of the final compounds were analyzed by melting point, combustion analysis, and 13C-NMR and 1H-NMR spectroscopy. Biological activities in vitro of the synthesized compounds as antagonists of the 5-HT2a and 5-HT7 receptors were determined by an independent laboratory.

Background. Both basal-like subtype and BRCA1-related breast cancers tend to have a poor overall prognosis and lack of effective treatments. Given that the lung cancer drug gefitinib and the leukemia drug dasatinib inhibit proteins also belonging to the molecular signature of this subtype, we and others hypothesized that they might be useful therapies for those two breast cancer subgroups. / Methods. Eight breast cancer cell lines were characterized by immunohistochemistry and western blotting and were treated with both drugs. Response was measured by using the sulphorhodamine B (SRB) assay. / Results. Two out of six basal-like cell lines were sensitive to gefitinib and five of six to dasatinib. BRCA1-related breast cancers were also responsive to dasatinib (three out of four). Moreover, EGFR and caveolin-1 act as markers for dasatinib sensitivity, but do not appear to be the primary targets of this drug. The presence of SRC but not ABL is necessary to achieve a response to dasatinib. / Conclusion. Dasatinib is more effective in the treatment of basal-like breast cancers than gefitinib and acts by inhibiting SRC and other molecules that are yet to be determined.

This thesis is engaged in the synthesis of polysubstituted pyrimidines with anti- inflammatory properties. Such molecules can inhibit production of prostaglandin E2 (PGE2). The aim of this study was to enhance water-solubility and anti-inflammatory efficacy of such derivatives via structural modifications of the lead scaffold. Among applied synthetic tools, the Suzuki-Miyaura cross-coupling was the prevalent reaction, however, many other synthetic procedures (Heck reaction, condensation, borylation, ozonolysis, nucleophilic substitution, etc.) were utilized as well. Overall, 43 final products were prepared. The anti-inflammatory efficacy (inhibition of PGE2 production) was successfully increased as the most potent compound achieved three orders of magnitude higher activity compared to the current lead structure WQE-134. Furthermore, no general influence of the length of the substituent in the C5 position of pyrimidine (C5pyr) on the anti-inflammatory efficacy of synthesized compounds was observed. Significant bioavailability obstacle in future development of the current lead WQE-134 is its poor solubility which was successfully enhanced by introduction of heteroatom bearing moieties to C5pyr. The most water-soluble compound achieved two orders of magnitude higher solubility than WQE-134 while...