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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.
41

Estudo do potencial analgésico e antiinflamatório do 3-(4-fluorfenil)-5-trifluormetil-1h-1-tosilpirazol em modelos de dor em camundongos / Study of the analgesic and antiinflammatory potential of 3-(4-fluorophenyl)-5-trifluoromethyl-1h-1-tosylpyrazole in pain models in mice

Oliveira, Sara Marchesan de 18 December 2009 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Pain is the most common complaint in the medical field and the identification of compounds that can effectively treat painful states without induction of side-effects remains a major challenge in biomedical research. The aim of the present study was to investigate the antinociceptive effect of a novel compound, 3-(4-fluorophenyl)-5-trifluoromethyl-1H-1-tosylpyrazole (compound A) in several models of pain in mice and compare with those produced by the known trifluoromethyl-containing pyrazole compound celecoxib. Compound A or celecoxib were administrated by oral (78 780 μmol/kg), intrathecal (9 22.5 nmol/site) or intracerebroventricular (9 22.5 nmol/site) routes. Oral administration of either compound A or celecoxib abolished the mechanical allodynia, but not the oedema caused by intraplantar injection of carrageenan. Similarly, compound A reduced the overt nociception, but not the oedema, produced by bradykinin or capsaicin. However, compound A (500 μmol/kg, orally) did not alter nociception nor oedema caused by intraplantar injection of prostaglandin E2 or glutamate, whereas celecoxib reduced only the nociception induced by the former. Moreover, oral and intrathecal administration of compound A or celecoxib also reduced the nociception induced by acetic acid. However, only celecoxib reduced the acetic acid-induced nociception when it was injected by the intracerebroventricular route. Finally, neither compound A nor celecoxib was able to produce antinociceptive effect in the tail-flick test or to alter the motor performance and the body temperature. Besides, compound A or celecoxib did not induce gastric lesion. Thus, compound A seems to be an interesting prototype for the development of novel analgesic drugs. / A dor é uma das maiores queixas na área médica e a identificação de compostos que possam tratar efetivamente os estados dolorosos, sem induzir efeitos colaterais, permanece um grande desafio na pesquisa biomédica. O objetivo do presente estudo foi investigar o efeito antinociceptivo de um novo composto 3-(4-fluorfenil)-5-trifluormetil-1H-1-tosilpirazol (composto A) em diferentes modelos de dor em camundongos e comparar os seus efeitos com aqueles produzidos por um pirazol contendo trifluormetil em sua estrutura, o celecoxibe. O composto A ou o celecoxibe foram administrados por via oral (78 780 μmol/kg), intratecal (9 22,5 nmol/sitio) ou intracerebroventricular (9 22,5 nmol/sitio). A administração oral do composto A ou do celecoxibe aboliram a alodínia mecânica, mas não o edema, causado pela injeção intraplantar de carragenina. Do mesmo modo, a administração do composto A reduziu a nocicepção, mas não o edema, produzido pela bradicinina ou capsaicina. Entretanto, o composto A administrado por via oral (500 μmol/kg) não alterou a nocicepção nem o edema causados pela injeção intraplantar de prostaglandina E2 (PGE2) ou glutamato. Já o celecoxibe, reduziu somente a nocicepção induzida pela PGE2. Além disso, a administração oral ou intratecal do composto A ou celecoxibe também reduziu a nocicepção induzida por ácido acético. Quando administrados por via intracerebroventricular, somente o celecoxibe foi capaz de reduzir a nocicepção induzida por ácido acético. Finalmente, o composto A ou o celecoxibe não alteraram a nocicepção térmica aguda, a performance motora ou a temperatura corporal dos animais, nem produziram lesões gástricas quando administrados por via oral. Consequentemente, o composto A parece ser um interessante protótipo para o desenvolvimento de novas drogas analgésicas.
42

Síntese de 1,1-dimetiletil-1h-pirazóis em líquidos iônicos / Synthesis of 1,1-dimethylethyil-1h-pyrazoles in ionic liquids

Marzari, Mara Regina Bonini 08 July 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work describes the synthesis of a series of pyrazoles from enaminoketones (RC(O)CH=CHNMe2 where R = hexyl, dimethoxymethyl, Ph, 4-Me-C6H4 4-F-C6H4, 4-Cl-C6H4, 4-Br-C6H4, 4-O2N-C6H4, thien-2-yl, fur-2-yl, pyrrol-2-yl, pyridin-2-yl) and N-tert-butilhidrazine hydrochloride. In order to get the best reaction media, reactions were carried out in different ionic liquids such as: [BMIM][BF4], [BMIM][Br], [OMIM][BF4], [BMIM][PF6], [DBMIM][Br], [DBMIM][BF4], [BMIM][OH], [BMIM][SCN], [HMIM][HSO4] and [HMIM][CF3CO2], with different physical and chemical. The behavior of each type of ionic liquid was discussed and the best yield for the cyclocondensation reactions studied was obtained using [BMIM][BF4]. Furthermore, also was a series of pyrazoles from the enones ([CF3C(O)CH=C(R)(OR1], where R1 = Me, Et and R = H, Me, Ph, 4-Me-C6H4, 4-MeOC6H4, 4-F-C6H4, 4-Cl-C6H4, 4-Br-C6H4, fur-2-yl, thien-2-yl and naphthalen-2-yl) and hydrochloride N-tert-butilhydrazine in the presence of pyridine was obtained. The products were obtained as a mixture of isomers. In some cases, it was possible to separate the isomers by washed with hexane. One of the crystalline compounds was analyzed by X-ray diffraction to confirm its structure. / Este trabalho descreve a síntese de uma série de pirazóis a partir da reação de enaminonas (RC(O)CH=CHNMe2 onde R = hexil, dimetoximetil, Ph, 4-Me-C6H4, 4-F-C6H4, 4-Cl-C6H4, 4-Br-C6H4, 4-O2N-C6H4, tien-2-il, fur-2-il, pirrol-2-il, piridin-2-il) com cloridrato de N-tert-butilhidrazina. A fim de estabelecer as melhores condições para a reação, foram testados diferentes líquidos iônicos ([BMIM][BF4], [BMIM][Br], [OMIM][BF4], [BMIM][PF6], [DBMIM][Br], [DBMIM][BF4], [BMIM][OH], [BMIM][SCN], [HMIM][HSO4] e [HMIM][CF3CO2]) com propriedades físicas e químicas diferentes. O comportamento de cada tipo de líquido iônico foi discutido e o melhor rendimento para a reação de ciclocondensação estudada foi obtido utilizando [BMIM][BF4]. Além disso, foram sintetizados N-tert-pirazóis a partir da reação de enonas trifluormetiladas ([CF3C(O)CH=C(R)(OR1], onde R1 = Me, Et e R = H, Me, Ph, 4-Me- C6H4, 4-MeO-C6H4, 4-F-C6H4, 4-Cl-C6H4, 4-Br-C6H4, fur-2-il, tien-2-il e naftil) com cloridrato de N-tert-butilhidrazina na presença de piridina e LI. Os produtos foram obtidos como uma mistura de isômeros. Em alguns casos foi possível a separação da mistura isomérica por lavagem com hexano. Um dos compostos cristalinos foi analisado por Difratometria de Raios-X para confirmar a sua estrutura.
43

Pyrazole and pyrazolylethylamine nickel(II) and palladium(II) complexes as catalysts for olefin oligomerization and Friedel-Crafts reactions

Moeti, Lerato Petunia 29 June 2015 (has links)
M.Sc. (Chemistry) / This study deals with the synthesis of nitrogen-donor pyrazole- and pyrazolylethylamine compounds, their reactions with palladium(II) and nickel(II) precursors to form complexes and the applications of theses palladium(II) and nickel(II) complexes as catalysts for ethylene oligomerization reactions and reactions of higher α-olefins in Friedel-Crafts alkylation of aromatic solvents. A series of ligands, 3,5-di-tert-butyl-1H-pyrazole (L3), 3,5-diphenyl-1H-pyrazole (L4), 5-phenyl-3-(trifluoromethyl)-1H-pyrazole (L5) were synthesized using appropriate amounts of diketones and hydrazine hydrate; while ligands, 2-(1H-pyrazol-1-yl)ethylamine (L6), 2-(3,5-dimethyl-1H-pyrazol-1-yl)-ethylamine (L7), 2-(3,5-di-tert-butyl-1H-pyrazol-1-yl)-ethylamine (L8), 2-(3,5-diphenyl-1H-pyrazol-1-yl)-ethylamine (L9) and 2-(5-phenyl-3-(trifluoromethyl)-1H-pyrazol-1-yl)ethylamine (L10) were prepared via the N sp3 alkylation of the corresponding pyrazoles with bromoethylamine Reactions of L1-L5 with [PdCl2(CNMe)2] formed five complexes of general formula [PdCl2 (L)2] {L = L1 (2.1), L2 (2.2), L3 (2.3), L4 (2.4) and L5 (2.5)}. Similarly [NiBr2(DME)] formed five complexes of general formula [NiBr2(L)2] {L = L1(2.6), L2 (2.7), L3 (2.8), L4 (2.9) and L5 (2.10)}. Complexes 2.1-2.10 were synthesized in a 2:1 mole ratio of ligand and metal precursor. Reactions of L6-L10 with [PdCl2(MeCN)2] yielded complexes 3.1-3.5 respectively. Ligands L6-L10 were also complexed with NiCl2.6H2O to give complex 3.6 while [NiCl2(DME)] and [NiBr2(DME)] gave complexes 3.7-3.8 and 3.9-3.13 respectively...
44

Pyrazolyl nickel and palladium complexes as catalysts for ethylene oligomerization and olefins and carbon monoxide co-polymerization reactions

Obuah, Collins 20 August 2012 (has links)
M.Sc. / This study describes the synthesis of pyrazolyl palladium and nickel complexes and their applications as catalysts for the co-polymerization of olefins with carbon monoxide and also as ethylene oligomerization catalysts. A series of compounds, 2-(3,5-dimethyl-pyrazol-1-yl)-ethyl]-pyridin-2-ylmethylene-imine (L1), 2-(3,5-di-tert-butyl-pyrazol-1-yl)-ethyl]-pyridin-2-ylmethylene-imine (L2), 2-(3,5-dimethyl-pyrazol-1-yl)-ethyl]-thiophen-2-ylmethylene-imine (L3), 2-(3,5-di-tert-butyl-pyrazol-1-yl)-ethyl]-thiphen-2-ylmethylene-imine (L4), 2-(3,5-dimethyl-pyrazol-1-yl)-ethyl]-5-bromothiophen-2-ylmethylene-imine (L5), 2-(3,5-di-tert-butyl-pyrazol-1-yl)-ethyl]-2bromothiophen-2-ylmethylene-imine (L6), 2-(3,5-dimethyl-pyrazol-1-yl)-ethyl]-pyrrol-2-ylmethylene-imine (L7) and 2-(3,5-di-tert-butyl-pyrazol-1-yl)-ethyl]-pyrrol-2-ylmethylene-imine (L8)] were prepared via Schiff base condensation of the appropriate amines and aldehydes. Reactions of L1-L6 and L8 with [PdClCH3(cod)] formed six complexes of general formula [PdClCH3(L)] {L = L1 (1), L2 (2), L3 (3), L4 (4), L5 (5) and L6 (6)} and [Pd(L8)2] (7). Complexes 1-6 were converted to the cationic compounds [PdCH3(L)]BAr4 {L = L1 (8), L2 (9), L3 (10), L4 (11), L5 (12) and L6 (13)} by the reaction of compounds 1-6 with the halide abstractor Na[BAr4] (where Ar = (3,5-(CF3)2C6H3) in a 1:1 mole ratio. For compounds 8 and 9 the cationic species were stabilized by the coordination of the pyrazolyl units of the ligands, which were uncoordinated in the parent palladium complexes 1 and 2. The cationic complexes 10-13, however, were stabilized by v coordination of NCCH3 to the palladium centre. Complexation of L1, L2, L5 and L6 with [PdCl2(NCCH3)2] gave the palladium dichloro complexes [PdCl2(L)], {L = L1 (14), L2 (15), L5 (16), and L6 (17)}. Compounds L1, L2, L7 and L8 were reduced to form compounds L9-L12 respectively and were reacted with [NiBr2DME] to form complexes [NiBr2(L)] {L = L9 (18), L10 (19), L11 (20) and L12 (21).
45

Quantum Perspectives on Physical and Inorganic Chemistry

Grimes-Marchan, Thomas V. 12 1900 (has links)
Applications of computational quantum chemistry are presented, including an analysis of the photophysics of cyclic trinuclear coinage metal pyrazolates, an investigation into a potential catalytic cycle utilizing transition metal scorpionates to activate arene C-H bonds, and a presentation of the benchmarking of a new composite model chemistry (the correlation consistent composite approach, ccCA) for the prediction of classical barrier heights. Modeling the pyrazolate photophysics indicates a significant geometric distortion upon excitation and the impact of both metal identity and substituents on the pyrazolates, pointing to ways in which these systems may be used to produce rationally-tuned phosphors. Similarly, thermodynamic and structural investigations into the catalyst system points to promising candidates for clean catalytic activation of arenes. The ccCA was found to reproduce classical reaction barriers with chemical accuracy, outperforming all DFT, ab initio, and composite methods benchmarked.
46

Molecular, Biochemical, and Toxicological Evaluation of Anticholinesterases for control of the Malaria Mosquito, Anopheles gambiae

Mutunga, James Mutuku 26 May 2011 (has links)
Pyrethroids are the only class of insecticides approved by the World Health Organization (WHO) for use in insecticide treated nets (ITNs), the first line of malaria vector control. Widespread resistance development to pyrethroids undermines current control efforts, and hence an urgent need for alternative chemistries. I report the evaluation of pharmacological differences between insect and vertebrate acetylcholinesterase (AChE) as well as selectivity and toxicity testing of new carbamate insecticides on Anopheles gambiae, the African malaria mosquito. AChE gorge pharmacology data revealed differences between insect and vertebrate AChE that can be exploited in the design of a bivalent insecticide. Toxicokinetic analysis showed that metabolic detoxication and cuticular penetration affect toxicity of carbamates in a manner dependent on the chemical structure. Structure activity relationships of side-chain branched N-methylcarbamates emphasized the importance of structural complementarity of ligands to the AChE catalytic active site and the substrate, acetylcholine. Monovalent pyrazoles and acetophenone oxime carbamates were toxic to both susceptible and carbamate-resistant mosquitoes carrying a G119S mutation within the catalytic site. A bivalent phthalimide-pyrazole carbamate and sulfenylated phenyl N-methyl carbamates were highly toxic when topically applied onto insect but less toxic by treated filter paper assays. In vitro evaluation of a molecular mosquito-selectivity model using AChE peripheral site ligands confirmed that selectivity of PRC 472 was due to presence of I70 in mosquito, which is Y70 in human AChE. The findings presented here are important steps in the on-going search of a mosquito-selective and resistance mitigating carbamate insecticide for control of malaria mosquitoes. / Ph. D.
47

Synthèse d'analogues de la pentamidine porteurs de plateformes hétérocycliques (rhodanine, benzimidazole, pyrazole et imidazole) et leurs évaluations biologiques / Synthesis of analogues of the pentamidine bearing heterocyclic platforms (rhodanine, benzimidazole, pyrazole and imidazole) and their biological evaluations

Ambeu, N'ta Christelle 16 December 2015 (has links)
Ce manuscrit de thèse concerne le développement d'une stratégie de synthèse multi-étapes de nouveaux composés comportant plusieurs plateformes hétérocycliques (rhodanine, benzimidazole, pyrazole et imidazole) à visée thérapeutique multiple contre la malaria, la leishmaniose, le cancer et les maladies neurodégénératives. Les pharmacomodulations de ces composés ont été élaborées sur la base du modèle de la pentamidine 35 comportant 2 motifs benzamidines (parties « Ouest » et « Est »). En effet, la substitution de sa partie « Ouest » par une plateforme rhodanine ou benzimidazole et de sa partie « Est » par un système aromatique plan ou système azole (pyrazole, imidazole) a permis d’accéder respectivement aux 5-arylidènes rhodanines (50, 58), aux dérivés ''aza'' (99,100) et aux dérivés ''aza azoles'' 174 qui sont des analogues de la pentamidine. Les rendements de ces composés sont respectivement compris entre 26 et 98%, 10 et 93% et 10 et 97%. L’ensemble des composés synthétisés dans les chapitres II, III et IV de ces travaux ont été l'objet d'évaluations pour leur activité antiproliférative sur les lignées cellulaires et pour leur activité inhibitrice sur les protéines kinases. / This thesis manuscript is focused on the development of multi-steps synthesis strategy of new compounds bearing several heterocyclic platforms (rhodanine, benzimidazole, pyrazole and imidazole) for multiple therapeutic use to fight malaria, leishmaniasis, cancer et neurodegenarative diseases. The pharmacomodulations of these compounds were developped from the design of pentamidine 35 which containins 2 fragments benzamidine (parts ''West'' and ''East''). Indeed, the substitution of its part ''West'' by a platform rhodanine or benzimidazole and its part ''East'' by an "azole" aromatic ring system (pyrazole, imidazole) lead respectively to 5-arylidene rhodanines (50, 58), to derivatives ''aza'' (99,100) and to derivatives ''aza azoles'' 174 which are pentamidine analogs. The chemical yields of these compounds are ranging respectively from 26 to 98%, 10 to 93% and 10 to 97%. All the compounds synthesized in the chapters II, III and IV of this research work were evaluated for their antiproliferative activity on tumoral cell lines and for their inhibitory activity on protein kinases.
48

Reações de ciclocondensação de cianoacetoidrazida com enonas halometil-substituídas / Cyclocondensation reactions of cyanoacetohydrazide with halomethyl-substituted enones

Moreira, Dayse das Neves 22 February 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The synthesis of thirteen 3-(R1), 4-(R2) and 5-(R3)-substituted 1-cyanoacetyl-5-hydroxy-4,5-dihydro-1H-pyrazoles from the cyclocondensation reaction of 4-alkoxy-3-alken-2-ones [R3C(O)C(R2)=C(R1)(OR), where R3 = CF3, CCl3, CHCl2, CO2Et; R2 = H, Me; R1 = H, Me, Et, Pr, Pentyl, c-Hexyl, Ph, and R = Me, Et] with cyanoacetohydrazide is reported. This reaction was carried out in different methodologies, firstly using water like solvent and following with ionic liquid ([BMIM]BF4). The results showed that when the ionic liquid was used as reaction media, the reaction time was drastically decreased and the yield was improved. 4,5-Dihydropyrazole (R1 = Me, R2 = H, R3 = CF3) was used as an important building block to the synthesis of cyanoenaminopyrazole from the condensation reaction with N,N-dimethylformamide dimethyl acetal. Benzilidene cyanoacetohydrazide was also employed to the synthesis of a series of seven 1- benzilidenepyrid-2-ones from the cyclocondensation reaction with 4-alkoxy-1,1,1-trifluoro-3-alken-2-ones [CF3C(O)C(R2)=C(R1)(OR), where R2 = H, Me; R1 = Me, Pr, Butyl, c-Hexyl, Ph, 4-MePh, e R = Me, Et]. The attainment of these compounds was only possible when the reaction was carried out in ionic liquid [BMIM]BF4. / Neste trabalho é descrita a síntese de uma série de treze 1-cianoacetil-5-hidróxi-4,5-diidro-1H-pirazóis 3-(R1), 4-(R2) e 5-(R3) substituídos a partir da reação de ciclocondensação de 4-alcóxi-3-alquen-2-onas [R3C(O)C(R2)=C(R1)(OR), onde R3 = CF3, CCl3, CHCl2, CO2Et; R2 = H, Me; R1 = H, Me, Et, Pr, Pentil, c-Hexil, Ph, e R = Me, Et] com cianoacetoidrazida. Esta reação foi realizada por duas metodologias diferentes, primeiramente utilizando água como solvente e, em um segundo momento, em líquido iônico ([BMIM]BF4). Os resultados obtidos mostraram que o líquido iônico [BMIM]BF4 demonstrou ser um importante meio reacional, proporcionando uma drástica redução no tempo da reação, bem como um aumento nos rendimentos. O 4,5-diidropirazol (R1 = Me, R2 = H, R3 = CF3) foi utilizado como um importante bloco precursor para a síntese do derivado cianoenaminopirazol através da reação de condensação com N,Ndimetilformamida dimetilacetal. A benzilideno-cianoacetoidrazida também foi empregada na síntese de uma série de sete 1-benzilidenopirid-2-onas através de uma reação de ciclocondensação com 4-alcóxi-1,1,1-trifluor-3-alquen-2-onas [CF3C(O)C(R2)=C(R1)(OR), onde R2 = H, Me; R1 = Me, Pr, Butil, c-Hexil, Ph, 4- MePh, e R = Me, Et]. A obtenção destes compostos foi possível apenas quando o líquido iônico [BMIM]BF4 foi utilizado como meio reacional.
49

Síntese de (5-trifluormetil-1H-pirazol-1-IL)(quinolin-4-IL)metanonas de interesse farmacológico / Synthesis of (5-trifluoromethyl-1H-pyrazol-1-YL)(quinolin-4-YL)methanones of pharmacological interest

Nogara, Pablo Andrei 22 July 2016 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A convergent synthesis of a series of 16 new polysubstituted (5-hydroxy-5-(trifluoromethyl)-4,5-dihydro-1H-pyrazol-1-yl)(quinolin-4-yl)methanones, starting from isatin and alky(aryl/heteroaryl) ketones, is described. The diheteroaryl methanones were achieved at yields of up to 95% by a (3 + 2) cyclocondensation reaction involving 4-alkyl(aryl/heteroaryl)-4-methoxy-1,1,1-trifluorobut-3-en-2-ones (by two-step reaction) and 2-alkyl(aryl/heteroaryl)-4-carbohydrazides (by three-step reaction). Subsequently, representative dehydrated heterocyclic derivatives were obtained from the respective 5-hydroxy-2-pyrazoline moieties by classical dehydration reactions, which resulted in the corresponding (5-(trifluoromethyl)-1H-pyrazol-1-yl)(quinolin-4-yl)methanones (three examples) at yields of 69 82%. The compounds were characterized by one- and two-dimensional 1H/13C NMR, X-ray diffraction, GC-MS and elemental analysis. The subsequent cytotoxicity evaluation showed that compounds with aromatic groups at the 2-position of the quinoline and a methyl moiety at the 3-position of the pyrazole have significant cytotoxicity in human leukocytes at high concentrations (200 μM). / Uma síntese convergente de uma série de 16 novos poli-substituídos (5-hidroxi-5-(trifluorometil)-4,5-di-hidro-1H-pirazol-1-il)(quinolin-4-il)metanonas, a partir da isatina e alquil(aril/heteroaril)cetonas, é descrito. As diheteroarilmetanonas foram obtidas com rendimentos de até 95% por uma reação de ciclocondensação (3 + 2) envolvendo 4-alquil(aril/heteroaril)-4-metóxi-1,1,1-trifluorbut-3-en-2-onas (reação em dois passos) e 2-alquil(aril/heteroaril)-4-carbohidrazidas (reação em três passos). Subsequentemente, os representantes desidratados dos heterociclos foram obtidos a partir das respectivas porções de 5-hidróxi-2-pirazolina por reações de desidratação clássicas, o que resultou nas correspondentes (5-(trifluormetil)-1H-pirazol-1-il)(quinolin-4-il )metanonas (três exemplos) com rendimentos de 69-82%. Os compostos foram caracterizados por RMN de 1H e 13C uni e bidimensional, difração de raios-X, CG-EM e análise elementar. As posteriores avaliações da citotoxicidade mostraram que os compostos com grupos aromáticos na posição 2 da quinolina e o grupo metila na posição 3 do pirazol, possuem significativa citotoxicidade em leucócitos humanos em concentrações elevadas (200 μM).
50

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.

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