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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.
1

Studies in the synthesis of pyrimidines, pyrazoles, and pyrazolo pyrimidines. New syntheses of 1, 3 and 5 substituted pyrazolo [3, 4-d] pyrimidines, including glycosides related to naturally occurring pyrimidines, imidazoles, purines and their nucleoside derivatives.

Hildick, Brian G. January 1978 (has links)
Some compounds, analogous to those found in naturally occurring systems, are found to possess chemotherapeutic activity. Some, in the form of their nucleoside or nucleotide derivatives, are valuable antimetabolites in that they may block normal RNA or DNA polymerisation, or may be incorporated into nucleic acids to form fraudulent, but not necessarily defective, polymers. Modification of natural ring systems, with a view to promoting chemotherapeutic activity is therefore of considerable interest; variation in the position and nature of the modification or ring substituent having a marked effect on chemotherapeutic activity. It is the purpose of this thesis to suggest methods for the facile synthesis of various uracils, pyrazoles and pyrazolo [3,4-d] - pyrimidines with alkyl, aryl and glycosyl substituents such that the nature of the ring substituents is easily varied. To this end a number of ethoxymethylene reagents were prepared which, by reaction with primary amines and hydrazines, would give acyclic intermediates capable of easy cyclisation into the uracil, pyrazole and pyrazolo [3,4-d] pyrimidine ring systems. Variation in the nature of specific substituents being determined by the choice of amine or hydrazine, other substituents being varied by modification of the original reagent. / S.R.G.
2

Synthèse et évaluation biologique d’inhibiteurs de FGFR3 de structure pyrazolooxadiazole, pyrido- et pyrazolopyrimidine / Synthesis and biological evaluation of inhibitors of FGFR3 pyrazolooxadiazole structure, pyrido-and pyrazolopyrimidine

Le Corre, Laurent 28 November 2012 (has links)
FGFR3 est un récepteur cellulaire impliqué dans de nombreux processus biologiques chez l’homme. La dérégulation de l’activité tyrosine kinase de FGFR3 est à l’origine d’anomalies de croissance osseuse et de certains cancers (myélome multiple, vessie). Le blocage de ce récepteur par des inhibiteurs compétitifs de l’ATP constitue une approche thérapeutique intéressante. La première partie de la thèse a concerné la préparation d’analogues du PD173074, inhibiteur nanomolaire de FGFR3, issu de l’industrie. Basée sur un squelette pyrido[2,3-d]pyrimidine, une chimiothèque de triazoles a été obtenue via une réaction de cycloaddition 1,3-dipolaire catalysée au cuivre (I). Parmi les 27 analogues synthétisés, le meilleur inhibiteur restaure ex vivo la croissance osseuse de fémurs de souris naines. Dans une seconde partie, nous avons développé deux nouvelles séries d’inhibiteurs de type pyrazolooxadiazole et pyrazolo[4,3-d]pyrimidine, à partir d’un précurseur pyrazole commun. Des procédures micro-ondes rapides et efficaces ont été utilisées pour conduire aux composés cibles. L’étude des relations structure-activité, réalisée sur une soixantaine de composés, a été validée par modélisation moléculaire. Le composé le plus actif présente une CI50 submicromolaire / FGFR3 is a cellular receptor involved in many human biological processes. Deregulated tyrosine kinase activity of the FGFR3 is at the origin of abnormal bone growth and some cancers (multiple myeloma, bladder). Blocking this receptor by ATP competitive inhibitors may constitute an interestingtherapeutic approach. The first part of this thesis concerned the preparation of analogues of PD173074, a nanomolar inhibitor of FGFR3, stemming from the industry. Based on pyrido [2,3-d] pyrimidine skeleton, a library of triazoles was obtained via copper (I)-catalyzed 1,3-dipolar cycloaddition. Among the 27 analogues synthesized, the best inhibitor restores bone growth of dwarf mice femurs ex vivo. In a second part, we have developed two new series of inhibitors based on pyrazolooxadiazole and pyrazolo [4,3-d] pyrimidine skeletons, derived from a common pyrazole precursor. Rapid and efficient microwave procedures were used to yield the target compounds. The study of structure-activity relationships, performed on sixty compounds, was confirmed by molecular modeling. The most active compound has a submicromolar IC50 value.
3

Studies in the synthesis of pyrimidines, pyrazoles, and pyrazolo pyrimidines : new syntheses of 1, 3 and 5 substituted pyrazolo [3, 4-d] pyrimidines, including glycosides related to naturally occurring pyrimidines, imidazoles, purines and their nucleoside derivatives

Hildick, Brian G. January 1978 (has links)
Some compounds, analogous to those found in naturally occurring systems, are found to possess chemotherapeutic activity. Some, in the form of their nucleoside or nucleotide derivatives, are valuable antimetabolites in that they may block normal RNA or DNA polymerisation, or may be incorporated into nucleic acids to form fraudulent, but not necessarily defective, polymers. Modification of natural ring systems, with a view to promoting chemotherapeutic activity is therefore of considerable interest; variation in the position and nature of the modification or ring substituent having a marked effect on chemotherapeutic activity. It is the purpose of this thesis to suggest methods for the facile synthesis of various uracils, pyrazoles and pyrazolo [3,4-d] - pyrimidines with alkyl, aryl and glycosyl substituents such that the nature of the ring substituents is easily varied. To this end a number of ethoxymethylene reagents were prepared which, by reaction with primary amines and hydrazines, would give acyclic intermediates capable of easy cyclisation into the uracil, pyrazole and pyrazolo [3,4-d] pyrimidine ring systems. Variation in the nature of specific substituents being determined by the choice of amine or hydrazine, other substituents being varied by modification of the original reagent.
4

Synthèse et fonctionnalisation de nouveaux dérivés tricycliques [6-5-6] polyhétéroaromatiques à visée thérapeutique potentielle / Synthesis and functionnalization of new polyheteroatomic tricycles [6-5-6] with therapeutic potential

Belaroussi, Rabia 06 February 2016 (has links)
La découverte de nouveaux candidats susceptibles de lutter contre différentes pathologies, en l’occurrence le cancer et les maladies neurodégénératives, constitue l’un des principaux objectifs de notre groupe de recherche. Dans ce contexte, les travaux de cette thèse ont pour but principal, la conception de deux nouvelles classes d’hétérocycles de structure planes, jusqu’à ce jour, très rarement étudiées, à savoir les pyrido[2’,1’ :1,5]pyrazolo[3,4-d]pyridazines et les pyrido[2’,1’ :1,5]pyrazolo[3,4-d]pyrimidines. Ce manuscrit est essentiellement dédié à un travail de méthodologie décrivant les différentes voies d’accès à ces originaux précurseurs tricycliques potentiellement modulables. La réactivité de ces synthons clés est ensuite étudiée vis-à-vis de réaction de substitutions nucléophiles aromatiques et de divers procédés de fonctionnalisation palladocatalysés (Suzuki-Miyaura, Buchwald-Hartwig, activation au PyBrOP-(hétéro)arylation) pour élaborer d’intéressantes chimiothèques construite autour de ces structures inédites ouvrant ainsi de nombreuses perspectives pharmacologiques. / The discovery of new candidates to fight against various diseases, namely cancer and neurodegenerative diseases, is one of the main goals of our research group. In this context, the main purpose of this thesis, is the design of two new classes of heterocyclic planar structure, to date, rarely studied, namely pyrido[2’,1’ :1,5]pyrazolo[3,4-d]pyridazines and pyrido[2’,1’ :1,5]pyrazolo[3,4-d]pyrimidines. This manuscript is essentially dedicated to a methodology work describing the different routes of access to these originals and potentially modular tricyclic precursors. The reactivity of these key synthons is then studied towards aromatic nucleophilic substitutions reactions and various palladocatalyzed methods of functionalization (Suzuki-Miyaura, Buchwald-Hartwig, activation PyBrOP-(hetero) arylation) to develop interesting libraries built around these unusual structures, thus opening numerous pharmacologicals perspectives.
5

Randy Akrofi MS Thesis

Randy Akrofi (15342217) 29 April 2023 (has links)
<p>  </p> <p>Quinolines are benzopyridine complexes present in many modern antimalarial, anticancer, anti-inflammatory, antimicrobial, and other useful pharmaceuticals and natural products.1,2 Quinolines form the scaffold for many potent anticancer drugs; this is because quinolines can undergo both nucleophilic and electrophilic substitution reactions, can be ingested and inhaled by humans without any harm, and possess a great deal of biological importance.3 My research has focused on synthesizing 3H-pyrazolo[4,3-f]quinoline analogs. The 3H-pyrazolo[4,3-f]quinoline scaffold was modified using various amine groups to obtain amide analogs as well as see how a change in the scaffold affects the anticancer activity of the synthesized complexes by screening them against kinases such as FLT3, CDK2, CDK4, and CDK9 to see if they are effective inhibitors. The synthesized complexes were then characterized using proton, carbon NMR and FTIR spectroscopy.</p>
6

Synthèse et fonctionnalisation du motif pyridine-[b]-bicyclique / Synthesis and functionalization of [b]-fused pyridine compounds

Lavrard-Meyer, Hubert 02 October 2017 (has links)
Une multitude de composés organiques présente une structure bicyclique azotée insaturée.Parmi ceux-ci, le motif pyridine-[b]-bicyclique est extrêmement fréquent, et se compose d’unepyridine accolée à un autre cycle aromatique. Cependant, les méthodes de synthèse de cescomposés sont aujourd’hui encore trop spécifiques. Les conditions réactionnelles ne sont pastoujours utilisables, ou ne permettent pas de préparer certains produits spécifiques. Afin des’affranchir de ces limitations, une nouvelle méthode de construction du cycle pyridine à partirdu motif ß–aminoacrylonitrile est proposée dans ce manuscrit, utilisant un alcène activé par unmotif trichlorométhyle.Outre la préparation de ces pyridines-[b]-bicycliques, la réactivité des pyrazolo[3,4-b]pyridines a été étudiée. Des réactions de fonctionnalisation de fin de synthèse ont étédéveloppées, qui exploitent des procédures basées sur la chimie du palladium. Trois positionsdes pyrazolopyridines ont pu être arylées, permettant d’accéder à de nouveaux composés / Bicyclic unsaturated structures containing one or more nitrogen atom appear in a widerange of organic compounds. In particular, the [b]-fused pyridine is a frequent structural motif,with striking biological activities. However, there is still a lack for general methods, withrespect to the reaction conditions or the scope. In order to override these limitations, a newsynthetic procedure for preparation of the pyridine ring starting from ß–aminoacrylonitrile isproposed. This procedure relies on a trichloromethyl-activated alkene.The reactivity of pyrazolo[3,4-b]pyridine, a subclass of [b]-fused pyridine, have beeninvestigated. Some late-stage functionnalization have been developped, relying on palladiumcatalyzed chemistry. Three positions of the pyrazolopyridine core have been arylated, thusgiving access to new structures
7

Synthèse de nouveaux dérivés pyrazolo[1,5-a]pyrimidiniques à visée biologique / Synthesis of new pyrazolo[1,5-a]pyrimidinic derivatives aiming at biological activity

Bassoude, Ibtissam 09 July 2012 (has links)
Nos travaux de thèse portent sur la mise au point de nouvelles méthodes de synthèse permettant l’accès de façon rapide et efficace à différents dérivés pyrazolo[1,5-a]pyrimidiniques diversement fonctionnalisés.La première partie de ce travail concerne l’étude et l’application de la condensation de la pyran-2-one avec les 5(3)-amino-3(5)-arylpyrazoles que ce soit par chauffage classique ou sous irradiation micro-onde. Par la suite, un nouveau procédé d’(hétéro)arylation pallado-catalysé direct régiosélectif a été mis à profit pour élaborer des pyrazolo[1,5-a]pyrimidines fonctionnalisées tant en position 3 que sur le méthyle situé sur le sommet 7 de la 5,7-diméthylpyrazolo[1,5-a]pyrimidine.Le dernier volet de ce mémoire a été consacré à la préparation des entités pyrazolo[1,5-a]pyrimidiniques substituées en position 7 par des motifs benzyliques et ce, via une procédure « one-pot », sous irradiation micro-onde, constituée d’une réaction d’arylation directe pallado-catalysée suivie d’une saponification-décarboxylation. / Our thesis works concern the development of new methods of synthesis allowing a rapid and effective access to variously functionalized pyrazolo [1,5-a] pyrimidines derivatives.First, we were explored the study and the application of the condensation of the pyran-2 one with 5(3)-amino-3 (5)-arylpyrazoles whether it is by classic heating or under microwaves. Indeed, we have described the first example of the direct and regioselective palladium-catalyzed (hetero)arylation of 5,7-dimethylpyrazolo[1,5-a]pyrimidine, the reaction may be inducted to occur at either an sp2 or an sp3 carbon atom.The last part of this report was dedicated to the preparation of some 7-substituted pyrazolo[1,5-a]pyrimidines via a one-pot two steps palladium-catalyzed direct CH-arylation followed by a saponification-decarboxylation.
8

Acilenaminonas: Síntese e Aplicação na Obtenção de Pirazóis, Pirazolo[3,4-d]piridazinonas e Pirazolo[1,5-a]pirimidinas / Acylenaminones: Synthesis and Application in the Obtaining of Pyrazoles, Pyrazolo[3,4-d]pyridazinones and Pyrazolo[1,5-a]pyrimidines

Rosa, Fernanda Andreia 19 May 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The regioespecific synthesis of a series of 14 N-acylated enaminones (52-88%) from the acylation reaction of secondary β-enamino ketones [RC(O)CH=CHNR1R2; R = Ph, 4- FC6H4, 4-NO2C6H4, thien-2-yl, CCl3, CF3; R1 = H; R2 = Bn, Ph, 4-NO2C6H4] with trifluoroacetic anhydride or ethyl oxalyl chloride in pyridine is reported. On the other hand, when tertiary enaminone precursors [R = Ph, 4-MeC6H4, 4-MeOC6H4, 4-BrC6H4, 4-ClC6H4, 4-FC6H4, 4-O2NC6H4, thien-2-yl, benzofur-2-yl, CCl3, CF3; R1,R2 = Me] were used, the acylation reaction led to a series of 17 C-acylated enaminones (75-95%). A series of 4-substituted-1H-pyrazole-5-carboxylates (73-94%) were obtained regiospecifically from the cyclocondensation reaction of non symmetrical enaminodiketones [RC(O)C(=CHNMe2)C(O)CO2Et; R = Ph, 4-MeOC6H4, 4-ClC6H4, 4-FC6H4, 4-O2NC6H4, thien-2-yl, benzofur-2-yl, CCl3, CF3] with tert-butylhydrazine or carboxymethylhydrazine. The reaction of these pyrazole-5-carboxylates (R = 4-MeOC6H4, 4-FC6H4, benzofur-2-yl, CF3) with hydrazine lead to synthesis of 4- substituted-pyrazolo[3,4-d]pyridazinones (74-96%). In addition, the reaction of enaminodiketones (R = Ph, 4-MeC6H4, 4-MeOC6H4, 4-BrC6H4, 4-ClC6H4, 4-FC6H4, 4- O2NC6H4, thien-2-yl, benzofur-2-yl) with 3-amino-5-methylpyrazole was performed, where a series of pyrazolo[1,5-a]pyrimidine-7-carboxylates were obtained regiospecifically (53-79%). / A síntese de uma série de 14 enaminonas N-aciladas regioespecificamente (52-88%) foi realizada a partir da reação de acilação de enaminonas secundárias [RC(O)CH=CHNR1R2; R = Ph, 4-FC6H4, 4-NO2C6H4, tien-2-il, CCl3, CF3; R1 = H; R2 = Bn, Ph, 4-NO2C6H4] com anidrido trifluoracético e com cloreto de etil oxalila em piridina. Quando foram utilizados como precursores enaminonas terciárias [R = Ph, 4-MeC6H4, 4-MeOC6H4, 4-BrC6H4, 4-ClC6H4, 4-FC6H4, 4-O2NC6H4, tien-2-il, benzofur-2-il, CCl3, CF3; R1,R2 = Me] a reação de acilação levou à obtenção regioespecífica de 17 enaminonas C-aciladas (75-95%). Uma série de 5-carboxietil-1H-pirazol 4-substituídos foi obtida regioespecificamente (73-94%) a partir da ciclocondensação das enaminodicetonas não simétricas [RC(O)C(=CHNMe2)C(O)CO2Et; R = Ph, 4-MeOC6H4, 4-ClC6H4, 4-FC6H4, 4-O2NC6H4, tien-2-il, benzofur-2-il, CCl3, CF3] com tert-butilidrazina ou carboximetilidrazina. A reação destes pirazóis (R = 4-MeOC6H4, 4-FC6H4, benzofur-2-il, CF3) com hidrazina monoidrato levou à síntese de pirazolo[3,4-d]piridazinona 4- substituídas (74-96%). Também foi realizada a reação de ciclocondensação de enaminodicetonas (R = Ph, 4-MeC6H4, 4-MeOC6H4, 4-BrC6H4, 4-ClC6H4, 4-FC6H4, 4-O2NC6H4, tien-2-il, benzofur-2-il) com 3-amino-5-metilpirazol onde as 7-carboxietilpirazolo[1,5-a]pirimidinas 6-substituídas foram obtidas regioespecificamente (53-79%).
9

Bi-heterociclos a partir do Ácido Levulínico: Síntese de 5-[(5-(trifluormetil)-5-hidroxi-(3-substituido)-4,5-diidro-1H-pirazol-1-il)-1-propan-1-ona-3-il]-2-metil-7-trifluormetil)pirazolo[1,5-a]pirimidinas / From Levulinic Acid to Biheterocycles: Synthesis of 5-[(5-(trifluoromethyl)-5-hydroxy-(3-substituted)-4,5-dihydro-1H-pyrazol-1-yl)-1-propan-1-one-3-yl]-2-methyl-7-trifluoromethyl)pyrazolo [1,5-a]pyrimidines

Rosales, Pauline Fagundes 04 March 2013 (has links)
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.
10

Synthesis and Biological Evaluation of Pyrazolo[1,5-a]pyrimidines and (4-Hydroxy-6-trifluoromethylpyrimidin-2-yl) guanidines

Singleton, Justin Dave 02 August 2021 (has links)
A microwave reactor was used to synthesize a series of novel 3,6-disubstituted or 3-substituted pyrazolo[1,5-a]pyrimidines in a total of 1 hour reaction time over 3 steps. The products were obtained in good to excellent yields (34-92%, ave = 52%) using a straightforward synthesis starting with the reaction of dimethylformamide-dimethylacetal with commercially available aryl acetonitriles (120C, 20 min). This was followed by treatment with H2NNH2 • HBr (120C, 20 min), and then reacted with either 1,1,3,3-tetramethoxypropane or a 2-aryl-substituted malondialdehydes (120C, 20 min). The resulting product was either collected on a sintered glass funnel or purified via column chromatography. The compounds were screened for anti-cancer activity against A2780 Ovarian and/or MCF7 breast cancer cell lines in vitro. The most active compounds were the 3-(4-(trifluoromethyl)phenyl)-6-[4-(2-(piperidin-1-yl)ethoxy]phenyl analogue and the 3-(2-fluorophenyl)-6-[4-(2-(4-methylpiperzin-1-yl)ethoxy]phenyl analogue, exhibiting EC50 values of 0.84 and 0.52 M respectively, which is 2-3 times more potent than Dorsomorphin. Several of the derivatives also showed promising activities against several viruses of emerging concern, including HBV, MERS Coronavirus, Zika, and Ebola. Use of a microwave reactor to synthesize N’-aryl/(alkyl) substituted N-[(4-hydroxy-6-phenyl)pyrimidin-2-yl]guanidines or N-[(4-hydroxy-6-trifluoromethyl)pyrimidin-2-yl]guanidines from the corresponding cyanamides with alkyl/aryl amines was achieved in good to excellent yields (39-96%, ave = 62%) in 10 minutes at 120C using only 1 equivalent of amine. Work-up was exceptionally simple, and involved collecting precipitated solids on a sintered glass funnel and washing with cold 2-propanol. Products were obtained in analytically pure form and required approximately 1 hour to prepare, start to finish. Compounds in this series showed early promise as potential inhibitors of A2780 Ovarian cancer, in vitro.

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