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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

Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae) / Chemical study of Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)

Sousa, Antonio Honório de January 2014 (has links)
SOUSA, Antonio Honório de. Estudo químico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae). 2014. 279 f. Tese (Doutorado em química)- Universidade Federal do Ceará, Fortaleza-CE, 2014. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-10-04T15:43:43Z No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2016-10-10T19:44:57Z (GMT) No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) / Made available in DSpace on 2016-10-10T19:44:57Z (GMT). No. of bitstreams: 1 2014_tese_ahsousa.pdf: 13571451 bytes, checksum: dcde11370b56473403f20f179360abe9 (MD5) Previous issue date: 2014 / The present work reports the chemical study related to the stem and the roots of Croton limae, collected in Andaraí/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10’-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data. / O presente trabalho relata o estudo químico do caule e das raízes de Croton limae, coletado no município de Andaraí-BA. A investigação fitoquímica do extrato etanólico do caule levou ao isolamento de dois diterpenos do tipo caurano, ácido ent-caur-16-en-18-oico e ácido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigação do extrato hexânico das raízes levou ao isolamento de um triterpeno, ácido acetilaleuritólico, do dímero inédito ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanólico das raízes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosídeo, e três diterpenos clerodanos inéditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e ácido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromáticas derivadas do ácido ent-caur-16-en-18-oico e os respectivos ésteres metílicos dos ácidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos através de reações de redução do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro através da biotransformação deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotóxica, utilizando linhagens de células tumorais de ovário (OVCAR-8), glioblastoma (SF-295) e colón (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e ácido ent-17(α-pinen-10’-il)-15-oxocauran-18-oico apresentaram atividade. Os metabólitos secundários foram isolados através de técnicas cromatográficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusão molecular e cromatografia líquida de alta eficiência. A determinação estrutural foi realizada através de métodos físicos (ponto de fusão e rotação óptica) e do uso de técnicas espectroscópicas e espectrométricas como infravermelho (IV), espectrometria de massas de alta resolução e ressonância magnética nuclear de hidrogênio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, além de comparação com dados da literatura.
2

Estudo quÃmico de Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae) / Chemical study of Croton Limae A. P. S. Gomes, M. F. Sales & P. E. Berry (Euphorbiaceae)

Antonio HonÃrio de Sousa 22 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / The present work reports the chemical study related to the stem and the roots of Croton limae, collected in AndaraÃ/BA. The phytochemical investigation of ethanol extract from the stem lead to the isolation of two kaurane-type diterpenes, ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid, two clerodane-type diterpenes, 3,12-dioxo-15,16-epoxy-4α-hydroxycleroda-13(16),14-diene and 3-oxo-4α-hydroxy-13,14,15,16-tetranorclerodan-12-oic acid, and the flavonoid quercetin 3-O-β-D-glucopyranoside. The investigation of the hexane extract from the roots lead to the isolation of one triterpene, acetyl aleuritolic acid, the new dimer ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid, two news clerodane diterpenes, 3-oxo-15,16-epoxy-4α,12-dihydroxycleroda-13(16),14-diene and 15,16-epoxy-3α,4α,12-trihydroxycleroda-13(16),14-diene, one halimane-type diterpene, 15,16-epoxy-3α,12-dihydroxyhalima-5(10),13(16),14-triene and the mixture of steroids β-sitosterol and stigmasterol. From the ethanol extract of the roots, it was possible to isolate the flavonoids kaempferol 3-O-β-glucopyranoside and ombuine 3-O-β-rutinoside and the three new clerodane diterpenes 3α,4α,15,16-tetrahydroxyclerod-13-ene, 6-(β-D-glucopyranosyl)-3,12-dioxo-15,16-epoxi-4α-hydroxycleroda-13(16),14-dieno and 3-oxo-4α,12-dihydroxy-14,15,16-trinorclerodan-13-oic acid. Four aromatic derivatives amides from ent-kaur-16-en-18-oic acid were prepared through nucleophilic substitutive reactions. The corresponding methyl esters from the ent-kaur-16-en-18-oic acid and ent-kaur-16-en-15-oxo-18-oic acid were also obtained. Two new derivatives from 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno were prepared through reduction reaction and another one by the biotransformation of diterpene, made by the fungus Rhizopus stolonifer. Some isolated compounds and derivatives were submited to cytotoxic activity using ovarian (OVCAR-8), glioblastoma (SF-295) and colon (HCT-116) cell lines, and the compounds ent-kaur-16-en-15-oxo-18-oic acid and ent-17(α-pinen-10â-yl)-15-oxokauran-18-oic acid registered activity during preliminaries assays. The secondary metabolites were isolated through usual chromatography techniques, using thin layer chromatography, column chromatography, size exclusion chromatography and high performance liquid chromatography. The determination of the structure of the isolated compounds was performed through physical (melting point and optical rotation) and spectrometric techniques, such infrared (IR), high resolution mass spectrometry and nuclear magnetic resonance (NMR), including bidimensional experiments, and comparison with literature data. / O presente trabalho relata o estudo quÃmico do caule e das raÃzes de Croton limae, coletado no municÃpio de AndaraÃ-BA. A investigaÃÃo fitoquÃmica do extrato etanÃlico do caule levou ao isolamento de dois diterpenos do tipo caurano, Ãcido ent-caur-16-en-18-oico e Ãcido ent-caur-16-en-15-oxo-18-oico, dois diterpenos do tipo clerodano, 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α-hidroxi-13,14,15,16-tetranorclerodan-12-oico, e do flavonoide 3-O-β-D-glicopiranosilquercetina. A investigaÃÃo do extrato hexÃnico das raÃzes levou ao isolamento de um triterpeno, Ãcido acetilaleuritÃlico, do dÃmero inÃdito Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico, de dois novos diterpenos clerodanos, 3-oxo-15,16-epoxi-4α,12-dihidroxicleroda-13(16),14-dieno e 15,16-epoxi-3α,4α,12-trihidroxicleroda-13(16),14-dieno, um diterpeno do tipo halimano, 15,16-epoxi-3α,12-dihidroxihalima-5(10),13(16),14-trieno, e da mistura dos esteroides β-sitosterol e estigmasterol. Do extrato etanÃlico das raÃzes foram isolados dois flavonoides, 3-O-β-D-glicopiranosilcanferol e ombuina-3-O-β-rutinosÃdeo, e trÃs diterpenos clerodanos inÃditos, 3α,4α,15,16-tetrahidroxicleroda-13-eno, 6-(β-D-glicopiranosil)-3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e Ãcido 3-oxo-4α,12-dihidroxi-14,15,16-trinorclerodan-13-oico. Foram preparadas quatro amidas aromÃticas derivadas do Ãcido ent-caur-16-en-18-oico e os respectivos Ãsteres metÃlicos dos Ãcidos ent-caur-16-en-18-oico e ent-caur-16-en-15-oxo-18-oico. Foram preparados dois derivados reacionais obtidos atravÃs de reaÃÃes de reduÃÃo do diterpeno clerodano 3,12-dioxo-15,16-epoxi-4α-hidroxicleroda-13(16),14-dieno e outro atravÃs da biotransformaÃÃo deste diterpeno pelo fungo Rhizopus stolonifer. Alguns compostos isolados e derivados foram submetidos a testes de atividade citotÃxica, utilizando linhagens de cÃlulas tumorais de ovÃrio (OVCAR-8), glioblastoma (SF-295) e colÃn (HCT-116), onde testes preliminares indicaram que os compostos ent-caur-16-en-15-oxo-18-oico e Ãcido ent-17(α-pinen-10â-il)-15-oxocauran-18-oico apresentaram atividade. Os metabÃlitos secundÃrios foram isolados atravÃs de tÃcnicas cromatogrÃficas usuais, utilizando cromatografia em camada delgada, cromatografia em coluna, cromatografia por exclusÃo molecular e cromatografia lÃquida de alta eficiÃncia. A determinaÃÃo estrutural foi realizada atravÃs de mÃtodos fÃsicos (ponto de fusÃo e rotaÃÃo Ãptica) e do uso de tÃcnicas espectroscÃpicas e espectromÃtricas como infravermelho (IV), espectrometria de massas de alta resoluÃÃo e ressonÃncia magnÃtica nuclear de hidrogÃnio (RMN 1H) e carbono-13 (RMN 13C), incluindo experimentos bidimensionais, alÃm de comparaÃÃo com dados da literatura.
3

Studies on cardiovascular and hepatic effects of trans-dehydrocrotonin, a clerodane diterpene isolated from Croton cajucara benth (sacaca) / Estudo dos efeitos cardiovasculares e hepÃticos da trans-desidrocrotonina (t-DCTN), um diterpeno clerodano obtido do Croton cajucara Benth. (sacaca).

Regilane Matos da Silva Prado 20 April 2005 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Croton cajucara Benth (Euphorbiaceae) is a popular medicinal plant in the Amazon region of Brazil for the treatment of liver and kidney disorders and also to lower blood cholesterol. The trans-dehydrocrotonin (t-DCTN), is the major clerodane diterpene isolated from the stem bark of Croton cajucara, that showed gastroprotective, hypoglycemic and hypolipidemic effects. Since drugs that possess pharmacological properties are often associated with contradictory cardiovascular and hepatic effects with possible cytoprotection or cytotoxicity properties, the present study aimed to examine the effects of t-DCTN (i) in the tests of lethality to Artemia sp and in primary cultures of mesencephalic and hepatic cells in vitro; (ii) on hepatotoxicity induced in vivo by acetaminophen or galactosamine/LPS in mice and (iii) on arterial blood pressure and heart rate in vivo, and on chronotropism and inotropism on isolated preparations of rat atria and aortic rings. The t-DCTN (0.3 to 300 Micromolar) demonstrated low toxicity to Artemia sp (LC50 of 670  80 Micromolar), and manifested no per se cytotoxicity on primary cultures of mesencephalic cells but could effectively revert the reduced cell viability induced by neurotoxin, 6-OHDA (200 Micromolar). On the other hand, t-DCTN (0.3â300 Micromolar) displayed cytotoxicity similar to ethanol (50-400 Milimolar) in primary cultures of hepatocytes. It, however offered hepatoprotection against acetaminophen (500 mg/kg)-induced hepatotoxicity in mice, evidenced from biochemical parameters of hepatic glutathione, and malonaldehyde, and serum AST and ALT levels. Nevertheless, the histological scores in liver tissues were not significantly altered by t-DCTN pretreatment. t-DCTN pretreatment also offered protection against galactosamine/LPS-induced hepatotxcity through restoration of glutathione and reductions in serum AST and ALT levels. In pentobarbital sodium anesthetized normotensive rats, t-DCTN produced hypotensive and bradycardia responses in a dose-dependent manner. The hypotensive effect of t-DCTN (10 mg/kg) was not affected by atropine, propranolol or hexamethonium but was abolished by L-NAME. In isolated right atria, t-DCTN inhibited the spontaneous beating but it was unable to reduce the isoproterenol-induced increase in heart beat. The inotropism was unchanged in the presence of t-DCTN in isolated left atria. In isolated rat aortic rings, t-DCTN relaxed the tonic contraction induced by phenylephrine (1 Micromolar), which was abolished in endothelium denuded or in L-NAME treated tissues. t-DCTN possessed low toxicity to Artemia sp; is devoid of neurotoxicity to mesencephalic cells; either induced hepatotoxicity or hepatoprotection, depending on the models used, and further suggested a possible inhibitory action on cytocrhrome-P450. The hypotensive action of t-DCTN may possibly involve in part the nitric oxide release from endothelium, and in part a direct relaxant effect on vascular smooth muscle. Taken together the data available in literature with the present observations suggest a caution while extrapolating animal data for a promising therapeutic utility of t-DCTN especially in the treatment of hepatic disorders or diabetes associated pathologies. / Croton cajucara Benth. (Euphorbiaceae), planta medicinal da regiÃo AmazÃnica do Brasil, à usada no tratamento de desordens hepÃticas, renais e hipercolesterolemia. A transdesidrocrotonina (t-DCTN), principal diterpeno clerodano isolado da casca do caule do CrÃton cajucara, possui efeito gastroprotetor, hipoglicÃmico e hilpolipidÃmico. Uma vez que substÃncias com esse perfil farmacolÃgico sÃo geralmente associadas a efeitos contraditÃrios sobre o sistema cardiovascular ou hepÃtico com possÃveis propriedades citoprotetora ou citotÃxica, o presente estudo objetivou avaliar os efeitos da t-DCTN (i) no teste de toxicidade para Artemia sp e para cultura de cÃlulas mesencefÃlicas primÃrias e cÃlulas hepÃticas in vitro; (ii) na toxicidade induzida in vivo por acetaminofeno ou galactosamina/LPS em camundongos e (iii) na pressÃo arterial mÃdia e freqÃÃncia cardÃaca in vivo, e no cronotropismo e inotropismo em Ãtrio isolado e anÃis de aorta isolada de rato. A t-DCTN (3-300 Micromolar) possui baixa toxicidade para Artemia sp (CL50 = 670  80 Micromolar) nÃo sendo detectada atividade citotÃxica da t-DTCN sobre cÃlulas mesencefÃlicas primÃrias per si, revertendo a diminuiÃÃo da viabilidade celular induzida por 6-OHDA (200 Micromolar). Por outro lado, a t-DCTN (0,3-300 Micromolar) demonstrou citotoxicidade semelhante ao etanol (50-400 Milimolar) em cultura primÃria de hepatÃcitos de rato de acordo com os teste do MTT, embora tenha apresentado proteÃÃo na hepatotoxicidade induzida por acetaminofeno (500 mg/kg) em camundongos, pelos testes da glutationa, malonaldeÃdo, AST e ALT em contraste, os escores histolÃgicos de tecido hepÃtico de camundongos nÃo foram significativamente alterados pela t-DCTN para cÃlulas tratadas com acetaminofeno, mas mostrou hepatoproteÃÃo na lesÃo induzida por galactosamina/LPS, revertendo os nÃveis de glutationa induzida pela hepatotoxina os nÃveis sÃricos de AST e ALT. Em animais normotensos anestesiados com pentobarbital, a t-DCTN produziu hipotenÃÃo e bradicardia de forma dose dependente. A hipotenÃÃo induzida por t-DCTN (10 mg/kg) nÃo foi alterada pelo prÃ-tratamento com atropina, propranolol e hexametÃnio, sendo reduzida pelo L-NAME. A t-DCTN inibe a freqÃÃncia de contraÃÃo espontÃnea de Ãtrio direito isolado, mas nÃo interfere no aumento dos batimentos atriais induzido pelo isoproterenol. O inotropismo nÃo foi alterado pela t-DCTN em Ãtrio esquerdo isolado. A t-DCTN à capaz de relaxar contraÃÃes submaximais de fenilefrina (1 Micromolar), sendo seu efeito parcialmente inibido pela retirada do endotÃlio ou pela presenÃa de L-NAME. Portanto, a t-DCTN possui baixa toxicidade para Artemia sp, nenhuma neurotoxicidade para cÃlulas mesencefÃlicas, hepatotoxicidade e hepatoproteÃÃo, dependendo da tÃcnica utilizada, sugerindo uma possÃvel aÃÃo inibitÃria no citocromo P450. A hipotenÃÃo induzida pela t-DCTN provavelmente se deve a sua aÃÃo combinada bradicardizante e vasodilatadora sendo esse efeito parcialmente mediado pela liberaÃÃo de NO endotelial e parte por efeitos na musculatura lisa vascular. Em conjunto, os dados disponÃveis na literatura com as presentes observaÃÃes sugerem que a t-DCTN està envolvida com propriedades citotÃxicas bem como citoprotetoras e, portanto, cuidados deve ser tomados quanto a extrapolaÃÃo dos dados em animais para a promissora atividade terapÃutica, especialmente para tratamento de desordens hepÃticas ou patologias associadas à diabetes.
4

ContribuiÃÃo ao conhecimento quÃmico de Croton pedicellatus Kunth / Contribution to the knowledge of chemical Croton pedicellatus Kunth

Elton Luz Lopes 10 September 2012 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / O presente trabalho descreve o primeiro estudo quÃmico das folhas de Croton pedicellatus Kunth.(Euphorbiaceae), um arbusto, nativo da AmÃrica do Sul, popularmente conhecido como velame, nome dado a vÃrias espÃcies de Croton. O extrato etanÃlico das folhas foi submetido a procedimentos clÃssicos de cromatografia, incluindo Cromatografia LÃquida de Alta EficiÃncia (CLAE), resultando no isolamento, de 15 metabÃlitos secundÃrios: dois sesquiterpenos conhecidos como blumenol A e roseosÃdeo; cinco diterpenos clerodanos furÃnicos: 12,20:15,16-diepoxi-3-hidroxi-7,20-dioxocleroda-13(16),14-dien-18,2-olÃdeo; 12,20:15,16-diepoxi-2,8-dihidroxi-3-acetoxi-7,20-dioxocleroda-13(16),14-dien-18-oato de metila; 12,20:15, 16-diepoxi-2-hidroxi-3-acetoxi-7,20-dioxocleroda-13(16),14-dien-18-oato de metila; 12,20:15,16-diepoxi-3,8-dihidroxi-2-acetoxi-7,20-dioxocleroda-13(16),14-dien-18-oato de metila e 12,20:15,16-diepoxi-3-hidroxi-2-acetoxi-7,20-dioxocleroda-13(16), 14-dien-18-oato de metila; seis flavonoides: alpinumisoflavona; canferol; 3-O-glicopiranosilquercetina; 6ââ-O-p-cumaroil-β-icopiranosilcanferol (tilirosÃdeo), 6ââ-O-p-cumaroil-β-galactopiranosilcanferol e 6ââ-O-p-cumaroil-β-galactopiranosil-3â-metoxi canferol, alÃm dos esterÃides β-sitosterol e seu derivado 3-O-glicosilado. A determinaÃÃo estrutural de todos os metabÃlitos secundÃrios isolados foi realizada atravÃs do emprego de tÃcnicas espectromÃtricas como ressonÃncia magnÃtica nuclear de hidrogÃnio-1 e carbono-13 (RMN de 1H e de 13C uni e bidimensionais), espectroscopia na regiÃo do infravermelho (IV), espectrometria de massas de alta resoluÃÃo, obtida com ionizaÃÃo por electrospray e comparaÃÃo com dados da literatura. / The present work describes for the first time the chemical investigation from leaves of Croton pedicellatus Kunth. (Euphorbiaceae), a shrub, native to South America and popularly known as âvelameâ, name given to several Croton species. The ethanol extract from leaves was subjected to classical chromatographic procedures including high performance liquid chromatography (HPLC), resulting in the isolation of 15 secondary metabolites: two sesquiterpenes known as blumenol A and roseosÃdeo; five clerodane furan diterpenes: 12,20:15,16-diepoxy-3-hydroxy-7,20-dioxocleroda-13(16),14-dien-18,2-olide; methyl-12,20: 15,16-diepoxy-2,8-dihydroxy-3-acetoxy-7,20-dioxocleroda-13(16),14-dien-18-oate; methyl-12.20:15,16-diepoxy-2-hydroxy-3-acetoxy-7,20-dioxocleroda-13 (16),14-dien-18-oate; methyl-12,20:15,16-diepoxy-3,8- dihydroxy-2-acetoxy-7,20 -dioxocleroda-13(16),14-dien-18-oate; methyl-12,20:15,16-diepoxy-3-hydroxy-2-acetoxy-7,20-dioxocleroda-13(16),14-dien-18-oate, and six flavonoids: alpinumisoflavone, kaempferol, quercetin-3-glucoside, Kaempferol-3-β-D-(6-trans-p-coumaroyl)glucopyranoside (tiliroside), kaempferol-3-β-D-(6-trans-pcoumaroyl)galactopyranoside and kaempferol-3â-methoxy-3-β-D-(6-trans-pcoumaroyl)glucopyranoside, besides the steroids β-sitosterol and its derivative 3-glucosylated. The structure determination of all secondary metabolites isolated was performed by spectrometric techniques such as hydrogen-1 and carbon-13 nuclear magnetic resonance (1H NMR and 13C one/two- dimensional), infrared spectrometry (IR), high resolution mass spectrometry and comparison with literature data.

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