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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 fitoquÃmico das cascas das raÃzes de Lonchocarpus araripensis. / Phytochemical investigations root barks of Lonchocarpus araripensis.

Almir Freire de Lima 12 March 2007 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho descreve a investigaÃÃo quÃmica do extrato hexÃnico das cascas das raÃzes de Lonchocarpus araripeinsis (sinonÃmia: Derris araripensis), popularmente conhecida como angelim, coÃÃo ou sucupira-branca. Empregando mÃtodos clÃssicos de isolamento, como cromatografia gravitacional em coluna aberta e cromatografia a mÃdia pressÃo (flash), ambas tendo gel de sÃlica como adsorvente, foram isolados oito flavonÃides, cujas estruturas foram determinadas como: 6a,11a-dihidro-3,9-dimetoxi-6H-benzofuro[3,2c](1)benzopirano, 3,4,5,6-tetrametoxi-[2â,3â:7,8]-furanoflavana; 3,6-dimetoxi-1â,1â-dimetilcromeno-[2â,3â:7,8]-flavona; 3â,4â-metilenodioxi-5,6-dimetoxi-[2â,3â:7,8]-furanoflavona; 3,5,6-trimetoxi-[2â,3â:7,8]- furanodi-hidroflavana; 3,5,6-trimetoxi -[2â,3â:7,8]-furanoflavona; 2,5,6-trimetoxi-[2â,3â:7,8]- furanoflavanona e 2â,6â,5â-trimetoxi-[2â,3â:4â,3â]- furanodihidrochalcona. Os dois Ãltimos estÃo sendo registrados pela primeira vez na literatura. Em adiÃÃo aos flavonÃides, foram tambÃm isolados os triterpenos, Ãcido betulÃnico e lupeol. As estruturas de todas as substÃncias isoladas neste trabalho foram elucidadas atravÃs de mÃtodos espectroscÃpicos, principalmente RMN, incluindo seqÃÃncias de pulsos uni e bidimencionais, alÃm de comparaÃÃo com dados da literatura, especialmente RMN 13C. / This work describes the chemical investigation of the hexane extract from root barks of Lonchocarpus araripensis (syn.: Derris araripensis), popularly known as âangelimâ, âcocÃoâ or âsucupira-brancaâ. Using classic methods of isolation, such as silica gel chromatography and silica gel flash chromatography, eight flavonoids were isolated whose structures were established as: 6a,11a-dihydro-3,9-dimethoxy-6H-benzofuran[3,2c](1)benzopiran; (2,3-trans-3,4-cis)-3,4,5,6-tetramethoxy-[2â,3â:7,8]-furanflavan; 3,6-dimethoxy-1â,1â-dimethylcromene-[2â,3â:7,8]-flavone; 3â,4â-methylenedioxy-5,6-dimethoxy-[2â,3â:7,8]-furanflavone; 3,5,6-trimethoxy-[2â,3â:7,8]- furanodihidroflavan; 3,5,6-trimethoxy-[2â,3â:7,8]-furanflavone; 2,4â,5,6-tetramethoxy-[2â,3â:7,8]- furanflavanone e 2â,6â,5â-trimethoxy-[2â,3â:4â,3â]-furandihydrochalcone. The two later compounds are being described for the first time in the literature. In addition, it was also isolated the triterpenes betulinic acid and lupeol. The structures of all isolated compounds were elucidated by spectroscopic methods, particularly NMR, including uni and bidimensional pulse sequences and comparison with literature data.
2

ContribuiÃÃo ao conhecimento quÃmico de plantas do Nordeste do Brasil: Lippia affinis gracillis H. B. K / Contribution to Nordtheast the chemical knowledge of plants of Brazil: Lippia affinis gracillis H. B. K

Maria da ConceiÃÃo LÃbo Lima 11 December 2006 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / Este trabalho descreve a investigaÃÃo fitoquÃmica das raÃzes, folhas e talos de Lippia affinis gracillis H.B.K. (Verbenaceae), popularmente conhecida no Nordeste do Brasil como âalecrim de vaqueiroâ. A anÃlise cromatogrÃfica dos extratos hexÃnico e etanÃlico das raÃzes e folhas de Lippia aff. gracillis permitiu o isolamento e caracterizaÃÃo do lapachenol (1), dos triterpenos friedelinona (2), acetato de epifriedelanil (3), Ãcido 3-acetil oleanÃlico (6) e lantandeno-A (7), das mistura dos esterÃides -sitosterol e estigmasterol (4) e seus glicosÃdeos (5), do Ãcido graxo Ãcido tetraeicosanÃico (8), das quinonas tecomaquinona (9), microfila quinona (10) e 5-hidroxinafto[2,3b]furan-4,9-quinona (11), dos flavonÃides quercetina (12), hispidulina (13) e da 3-metilquercetina (14). O estudo da composiÃÃo quÃmica dos Ãleos essenciais das folhas e talos de Lippia aff. Gracillis por CGL/EM, apresentou pouca similaridade, sendo os constituintes majoritÃrios das folhas o carvacrol (54,4%) (59) e o p-cimeno (10,7%) (53), enquanto que nos talos foram o carvacrol (30,2%) (59) e o biciclogermacreno (16,7%) (63). Com os Ãleos das folhas e talos, o carvacrol e seus derivados metilado e acetilado foram realizados teste para determinaÃÃo das atividades: Larvicida (Aedes aegypti), moluscicida (Biomphalaria glabrata), antimicrobiana e antioxidante. Na determinaÃÃo estrutural dos metabÃlitos secundÃrios isolados, utilizou-se de tÃcnicas espectroscÃpicas como infravermelho e ressonÃncia magnÃtica nuclear de hidrogÃnio e carbono-13, incluindo tÃcnicas bidimensionais (COSY, HMQC e HMBC), e ainda comparaÃÃo com dados espectroscÃpicos de compostos autÃnticos descritos na literatura. / This work describes the phytochemical studies of the roots, leaves and stalks of Lippia affinis gracillis (Verbenaceae), popularly known in the Brazilian northeast as âalecrim de vaqueiroâ. Chromatographic analysis of hexanic and ethanol extracts of the roots and leaves of Lippia aff. gracillis allowed the isolation and characterization of lapachenol (1), of triterpenes friedelinone (2), epifriedelanyl acetate (3), oleanÃlic acid 3-acethyl (6) and lantandene-A (7), of the mixture steroids -sitosterol and stigmasterol (4) and their glycosides (5), of the fatty acid tetraeicosanoic (8), of the quinone tecomaquinone (9), microphyllaquinone (10) and 5-hydroxynaphto[2,3b]furan-4,9-quinone (11) and flavonoids quercetine (12), hispiduline (13) and 3-methylquercetine (14). The chemical composition of essential oils Lippia aff. gracillis was identified by gas chromatography coupled to mass spectrometry (GCL/MS) study from the leaves and stalks presented similarity small, were major constituents from the leaves the carvacrol (54,4%) (59) of the pcymene (10,7%) (53), while that in the stalks were the carvacrol (30,2%) (59) and biciclogermacrene (16,7%) (63). With the essential oils from the leaves and stalks, the carvacrol and derivative methyled and acethyled from the carvacrol had been made the larvicidal activitys (Aedes aegypti), molluscicide (Biomphalaria glabrata), antibacterial and antioxidant. Structures determinations of all compounds had been established on the basis of spectroscopic techniques such as IR, 1D and 2D NMR (COSY, HMQC, HMBC), as well by comparison with the published data for structurally related compounds.
3

ContribuiÃÃo ao conhecimento quÃmico de plantas do Nordeste do Brasil: Cordia piauhiensis Fresen e Triphsia trifolia (Burm. f.) P.Wils / Contribution to Northeast the chemical Knowledge of plants of Brazil: Cordia piauhiensis Fresen e Triphasia trifolia (Burm. f.) P. Wils

Renata Paiva dos Santos 04 September 2007 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A composiÃÃo quÃmica do Ãleo essencial das folhas e frutos de Triphasia trifolia (Rutaceae) foi analisada por CG- DIC e CG-MS. Os constituintes majoritÃrios identificados para os Ãleos obtidos das folhas foram sabineno (39,2 e 33,8%) e mirceno (21,9 e 33,6%), enquanto os compostos majoritÃrios para o Ãleo dos frutos foram sabineno (35,5 e 22,8%), -pineno (21,2 e 29,9%) e -terpineno (18,4 e 12,9%). Os Ãleos das folhas apresentaram moderada atividade antimicrobiana. O decocto dos frutos tambÃm foi investigado levando ao isolamento das cumarinas isopimpinelina, (R)-biakangelicina e (S)-mexoticina. Das folhas foram isoladas as cumarinas (R)-biakangelicina, aurapteno, (S)-mexoticina, isosibiricina, isomerazina e coumurraina e, o flavonÃide vitexina. Todas cumarinas em CCD, mostraram atividade frente à enzima acetilcolinesterase. De Cordia piauhiensis Fresen (Boraginaceae), cinco saponinas triterpÃnicas foram isoladas. Suas estruturas foram caracterizadas como Ãcido 3-O-[-L-ramnopiranosil- (12)--D-glicopiranosil] pomÃlico, pomolato de 3-O-[-L-ramnopiranosil-(12)--Dglicopiranosil] 28-O--D-glicopiranosil-(16)--D-glicopiranosila, ursolato de 3-O-[- L-ramnopiranosil-(12)--D-glicopiranosil] 28-O--D-xilopiranosil-(12)- -Dglicopiranosil-( 16)--D-glicopiranosila, pomolato de 3-O-[-L-ramnopiranosil-(12)- -D-glicopiranosil] 28-O--D-glicopiranosila e oleanolato de 3-O-[-L-ramnopiranosil- (12)--D-glicopiranosil] 28-O--D-glicopiranosil-(16)--D-glicopiranosila. As estruturas foram estabelecidas usando uma combinaÃÃo das tÃcnicas de RMN 1D e 2D (1H- 1H-COSY, HMQC, HMBC, TOCSY e NOESY), ESIMS, alÃm de evidÃncias quÃmicas. / The chemical composition of the essential oils from leaves and fruits of Triphasia trifolia were analyzed by GC-FID and GC-MS. The major constituents identified for oils obtained from leaves were sabinene (39.2 and 33.8%) and myrcene (21.9 and 33.6%), while the prevalent compounds detected in fruit oils were sabinene (35.5 and 22.8%), -pinene (21.2 and 29.9) and -terpinene (18.4 and 12.9%). The leaf oils showed moderate antimicrobial activity. The fruit decoction was also investigated leading to the isolation of the coumarins isopimpinelin, (R)-byakangelicin and (S)-mexoticin. From the leaves the coumarins (R)-byakangelicin, aurapten, (S)-mexoticin, isosibiricin, isomerazin and coumurrayin and, the flavonoid vitexina were isolated. All coumarins showed cholinesterase inhibition on TLC test. From Cordia piauhiensis Fresen (Boraginaceae), five triterpenoid saponins were isolated. Their structures were characterized as 3-O--L-rhamnopyranosyl-(1_2)--Dglucopyranosyl pomolic acid, 3-O-[-L-rhamnopyranosyl-(12)--D-glucopyranosyl] pomolic acid 28-O-[-D-glucopyanosyl-(16)--D-glucopyranosyl] ester, 3-O-[-Lrhamnopyranosyl-( 12)--D-glucopyranosyl] ursolic acid 28-O-[-D-xilopyranosyl- (1_2)--D-glucopyanosyl-(16)--D-glucopyranosyl] ester, 3-O--L-rhamnopyranosyl- (12)--D-glucopyranosyl pomolic acid 28-O--D-glucopyranosyl ester and 3-O--Lrhamnopyranosyl-( 12)--D-glucopyranosyl oleanolic acid 28-O--D-glucopyranosyl- (16)--D-glucopyranosyl ester. The structures were established using a combination of 1D and 2D (1H-1H-COSY, HMQC, HMBC, TOCSY and NOESY) NMR techniques, ESIMS and chemical evidences.

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