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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.
11

Isolamento de constituintes e síntese de flavonoides encontrados em Poincianella pyramidalis (Fabaceae) e análise fitoquímica de Theobroma cacao (Malvaceae)

Oliveira, José Cândido Selva de January 2014 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2014-09-17T17:07:47Z No. of bitstreams: 1 TESE COMPLETA.pdf: 4364010 bytes, checksum: db848addf66479f547ccb64d058e01e0 (MD5) / Approved for entry into archive by Fatima Cleômenis Botelho Maria (botelho@ufba.br) on 2014-09-19T12:34:03Z (GMT) No. of bitstreams: 1 TESE COMPLETA.pdf: 4364010 bytes, checksum: db848addf66479f547ccb64d058e01e0 (MD5) / Made available in DSpace on 2014-09-19T12:34:03Z (GMT). No. of bitstreams: 1 TESE COMPLETA.pdf: 4364010 bytes, checksum: db848addf66479f547ccb64d058e01e0 (MD5) / CNPq e CAPES / Os extratos MeOH de Poincinella pyramidalis (caatingueira), obtidas da casca da raiz (PPCR) e das flores (PPF), bem como, as frações orgânicas obtidas por partição, foram submetidas a testes de atividade citotóxica, antioxidante e anticolinesterásica. O teste citotóxico contra Artemia salina revelou atividade moderada para fase AcOEt em PPCR. Assim como, a fase AcOEt de PPCR apresentou 75% de inibição no teste anticolinesterásico. Para a atividade antioxidante, as fase AcOEt e BuOH de PPF foi a mais ativa, sendo atribuída a presença de galato de metila (PPF3). Por meio de processos cromatográficos foi possível isolar da fase DCM de PPF as substâncias PPF1 (alcoóis graxos), PPF2a-b (β–sitosterol/estigmasterol), PPF3 (galato de metila) e PPF4 (α e β–amirina). Além dessas, foram isoladas da fase hexano de PPCR ésteres metílicos (PPCR1) e o biflavonoide 5,7-dihidroxi-4´-metoxiflavona-6α-2´´´,4´´´-dihidroxi-4´´- metoxidihidrochalcona (PPCR3). Da fase hidroMeOH de PPCR foram isoladas as substâncias PPCR2 (ácido 3,3´-dimetoxi-4-hidroxielagico-4´-β-D-xilopiranosideo) e outro biflavonoide PPCR4 (5-hidroxi-7,4´-dimetoxiflavona-3α-2´´´-hidroxi-4´´´,4´´- dimetoxidihidrochalcona). Sendo PPCR3 e PPCR4 inéditas na literatura. O extrato hexano de Theobroma cacao (cacau) obtido das sementes (STC) foi analisado por RMN e revelou presença de triacilglicerideos. A otimização e fracionamento do extrato MeOH de T. cacao utilizando CCC levou ao isolamento simultâneo de teobromina (2), teofilina (3) e cafeína (4), fase móvel hexano:AcOEt (2:3) e estacionária MeOH:H2O (1:1). Um método analítico foi desenvolvido empregando HPLC/DAD com coluna fase reversa C-18 para a quantificação de 2, 3 e 4 nos extrativos em fase ácida/básica e nas frações STC6-22 e STC23-67 obtidas por CCC. Assim, os teores de 2 e 4 para no extrato MeOH de T. cacao e frações obtidas por CCC foram determinados. A teofilina (3) detectada e quantificada na fração STC6-22 em baixa concentração (0,78 mg/g) em relação a 2 e 4. A apigenina (6) foi sintetizada utilizando dois métodos distintos (“A” e “B”). O metodo “B” apresentou rendimento de 74% em uma única etapa. A síntese de derivados O-metilados forneceu bons rendimentos (> 90%). As substâncias isoladas/sintetizadas foram submetidas à atividade anticolinesterasica do qual, são inativas. As mesmas foram elucidadas a partir de dados de IV, UV, EM, α[D], RMN de 1H e 13C (BB e APT), RMN de correlação (HMQC, HSQC e HMBC). / The MeOH extracts from Poincinella pyramidalis (caatingueira), obtained of bark root (PPCR) and flowers (PPF), as well the organic fractions obtained by partition, have been tested for cytotoxicity, antioxidant and anticholinesterasic activity. The cytotoxic test against Artemia salina showed moderate activity for AcOEt phase in PPCR. Well the EtOAc phase of PPCR showed 75% inhibition on anticholinesterasic test. For the antioxidant activity, the EtOAc and BuOH phase of PPF was the most active, being attributed to the presence of methyl gallate (PPF3). For chromatographic process was possible to isolate the DCM phase of PPF the substances PPF1 (fatty alcohols), PPF2a- b (β–sitosterol/stigmasterol), PPF3 (methyl galate) and PPF4 (α- and β–amirin). Besides these, were isolated from the hexane phase PPCR methyl esters (PPCR1) and the biflavonoid 5,7-dihidroxy-4´-methoxyflavone-6α-2´´´,4´´´-dihidroxy-4´´-methoxy dihidrochalcone (PPCR3). The HidroMeOH phase of PPCR were the isolated substances PPCR2 (3,3´-dimethoxi-4-hidroxyellagicacid-4´-β-D-xylopiranoside) and other biflavonoid PPCR4 (5-hidroxy-7,4´-dimethoxyflavone-3α-2´´´-hidroxy-4´´´,4´´- dimethoxydihidrochalcone). Being PPCR3 and PPCR4 unpublished in literature. Hexane extract of Theobroma cacao (cacau) obtained from the seeds (STC) was analyzed by NMR and revealed the presence of triacylglycerides. The optimization and fractionation of MeOH extract of T. cacao using CCC led to the simultaneous isolation of theobromine (2) Theophylline (3) and caffeine (4), mobile phase hexane:EtOAc (2:3) and stationary MeOH:H2O (1:1). An analytical method was developed employing HPLC/DAD with reverse phase column C-18 for the measurement of 2, 3 and 4 in the extractives acid/base phase and the STC6-22 and STC23-67 fractions obtained by CCC. So, the levels of 2 and 4 for the MeOH extract of T. cacao and fractions obtained by CCC were determined. Theophylline (3) detected and quantified in the fraction STC6-22 low concentration (0.78 mg/g) in relation the 2 and 4. Apigenin (6) was synthesized using two different methods ("A" and "B"). The method "B" had a yield of 74% in one step. The synthesis of O-methylated derivatives provided good yields (> 90%). The isolated/synthesized substances were submitted to anticholinesterasic activity which are inactive. The same were elucidated from data of IR, UV, MS, α[D], 1H NMR and 13C NMR (BB and APT) NMR correlation (HMQC, HSQC and HMBC).
12

Metab?litos especiais isolados de folhas e galhos de Ouratea ferruginea Engl. (Ochnaceae).

Fidelis, Queli Cristina 25 February 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-27T13:08:18Z No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) / Made available in DSpace on 2016-07-27T13:08:18Z (GMT). No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / This work describes the phytochemical study of the stems and leaves of Ouratea ferruginea Engl., Ochnaceae. The material for study was collected in the campus of Embrapa in Bel?m, Par? state, and identified by Dra Silvane Taveres Rodrigues. The compounds described in this phytochemistry investigation were isolated by the solvents partition and chromatographyc techniques of the extracts obtained by maceration at room temperature with hexane, ethyl acetate and methanol. The structures were determined through analysis of data provided by IR, 1H and 13C NMR (1D an 2D techniques), mass spectrometry including GCMS and HPLC-MS of natural compounds and some derivatives. From the stem dichloromethane extract friedelin, friedelinol, sitosterol, stigmasterol, campesterol, 3-b-O-Dglucopyranosyl- stigmasterol, 2,6-dimethoxy?benzoquinine, 2,6-dimethoxy-hydroquinone, the isoflavones: 5,4'-dihydroxy-7,3',5'-trimethoxy-isoflavone, 5-hydroxy-7,3',4',5'-tetramethoxyisoflavone, 5,4'-dihydroxy-7,3'-dimethoxy-isoflavone, 7,5-dihydroxy-3',4',5'-trimethoxyisoflavone, 7,5,4?-trihydroxy-3?,5?-dimethoxy-isoflavone, and ferulic and syringic aldehyde were isolated. From the dichloromethane partition of the methanol extract of the stem vanillic acid, 4 ((1E)-3-hydroxy-1-propenyl)-2-methoxyphenol and 3,5-dimethoxy-4-hydroxydihydrocinamaldehyde were isolated. From hexane fraction of methanol extract from the leaves lupeone was isolated, and from the dichloromethane methanol partition were identified the biflavonoids amentoflavone and 7-methyl-amentoflavone, known as sequoiaflavone, along with syringic acid. From the ethyl acetate of the methanol extracts partition the epicatechin which absolute configuration was defined by circular dichroism spectral analysis was isolated. The sequioflanove is been identified in Ochnaceae for the first time. From the polar fraction the total phenol were determined by adapted Folin-Denis and precipitation with casein methods and by NMR spectral analysis. / Este trabalho descreve o estudo fitoqu?mico de caule e folhas da esp?cie vegetal Ouratea ferruginea Engl, Ochnaceae. O material para estudo foi coletado no campus da Embrapa em Bel?m do Par? e identificado pela Dra Silvane Tavares Rodrigues. As subst?ncias descritas nesta investiga??o fitoqu?mica foram isoladas atrav?s de parti??o com solventes e t?cnicas cromatogr?ficos de extratos obtidos atrav?s de macera??o a frio com hexano, acetato de etila e metanol. As estruturas foram determinadas atrav?s da an?lise de dados fornecidos por espectrometria na regi?o do infravermelho, RMN 1H e 13C (t?cnicas 1D e 2D), de massas incluindo CG-EM e CLAE-EM das subst?ncias naturais e de alguns derivados. Do extrato em diclorometano do caule foram isolados friedelina, friedelinol, sitosterol, estigmasterol, campesterol, 3-b-O-D-glicopiranosil-estigmasterol, 2,6-dimetoxi benzoquinona, 2,6-dimetoxi hidroquinona, as isoflavonas 5,4?-diidroxi-7,3?,5?-trimetoxiisoflavona, 5,4?-diidroxi-7,3?-dimetoxi-isoflavona, 5-hidroxi-7,3?,4?,5?-tetrametoxiisoflavona, 7,5-diidroxi-3?,4?,5?-trimetoxi-isoflavona, 7,5,4?-triidroxi-3?,5?-dimetoxiisoflavona, al?m dos alde?dos sir?ngico e fer?lico. Da parti??o em diclorometano do extrato metan?lico do caule foram isolados ?cido van?lico, 4((1E)-3-hidroxi-1-propenil)-2- metoxifenol e 3,5-dimetoxi-4-hidroxi-diidrocinamalde?do. Das folhas foi isolada a lupeona na parti??o em hexano do extrato metan?lico; e na parti??o em diclorometano foram identificados os biflavon?ides amentoflavona e 7-metil-amentoflavona, conhecida como sequoiaflavona, e o ?cido sir?ngico. Na parti??o em acetato de etila foi isolado a epicatequina cuja configura??o absoluta foi definida com an?lise do espectro de dicro?smo circular. A sequioflavona est? sendo registrada pela primeira vez em Ochnaceae. Das fra??es polares foram determinados o teor de fen?is totais e taninos por m?todos de Folin-Denis e precipita??o com case?na, adaptados, al?m de an?lise com espectros de RMN.

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