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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.
71

Terpenos rearranjados da esponja Darwinella cf. oxeata com potencial leishmanicida / Rearranged terpenes from the marine sponge Darwinella cf. oxeata with leishmanicidal potential

Maria Camila Acevedo Ramirez 17 March 2016 (has links)
O extrato metanólico da esponja Darwinella sp. coletada na costa do Rio do Janeiro, exibiu atividade leishmanicida. O extrato bruto foi particionado em três frações: fração hexânica, fração de AcOEt e fração XAD (extração da fração orgânica do extrato aquoso mediante mistura de resinas XAD-2, XAD-4 e XAD-7). Cada uma das frações foi avaliada em bioensaio atividade leishmanicida, mostrando que a fração AcOEt apresentou 100% da morte dos parasitas. A fração de AcOEt foi fracionada usando cromatografia por exclusão de tamanho (Sephadex&reg LH-20) e extrações em fase sólida (SPE) com diferentes colunas pré-empacotadas. Os compostos foram isolados e purificados por cromatografia de alta eficiência acoplada a detector ultravioleta (CLAE-UV). Sete compostos foram isolados, dos quais quatro deles foram identificados espectroscopicamente. O membranolídeo, o éster metílico da oxeatamida A, a oxeatamida H e a oxeatina são diterpenos espongianos que possuem um esqueleto aplysulfurano nitrogenado, excetuando o membranolídeo. Tanto o éster metílico da oxeatamida A quanto a oxeatamida H, pertencem a uma série de compostos denominados de oxeatamidas. O membranolídeo, o éster metílico A e a oxeatina foram avaliados em teste de atividade antiparasitária contra Leishmania infantum, porém nenhum deles apresentou atividade leishmanicida. / The sponge Darwinella sp. was collected in Rio de Janeiro’s coast and its methanolic extract showed leishmanicidal activity. The crude extract was partitioned in three fractions: hexane, AcOEt and XAD fractions. This last one was obtained by resin adsorption (mixture of XAD-2, XAD-4 and XAD-7 resins) of organic constituents from the aqueous fraction and subsequent recovery by extraction from the resins mixture. All of three fractions were also tested in leishmanicidal bioassay. The AcOEt fraction promoted 100% of parasite death. This fraction was separated into less complex fractions by size exclusion chromatography (Sephadex&reg LH-20) and solid phase extractions (SPE). The compounds were isolated and purified by high-performance liquid chromatography (HPLC) combined with on-line UV detector. Seven substances were isolated, which four of them were spectroscopically identified. The membranolide, the oxeatamide A methyl ester, the oxeatamide H and the oxeatin are spongian diterpenes with nitrogenous aplysulphurane skeleton, except for the membranolide. The oxeatamides are a series of nitrogenous aplysulphurane metabolites that includes the oxeatamide A methyl ester and the oxeatamide H. All of these compounds, except the oxeatamide H, were evaluated for antiprotozoal activity against Leishmania infantum. None of these compounds displayed leishmanicidal activity.
72

Análise de terpenóides de espécies de Croton sect. Lamprocroton (Mull. Arg.) Pax (Euphorbiaceae) / Terpenoid analysis of species of Croton sect Lamprocroton (Mull. Arg.) Pax. (Euphorbiaceae)

Diego Amaral de Feliu 16 September 2011 (has links)
Croton é um gênero gigante de Euphorbiaceae com cerca de 1.300 espécies distribuídas em regiões tropicais e subtropicais da América, África, Ásia e Austrália. O Brasil é um importante centro de diversificação da espécie, com mais de 350 espécies descritas, sendo muitas endêmicas. Muitas espécies são utilizadas como plantas medicinais pelas populações locais, para o tratamento de diversos males, como câncer, diabetes, febre, hipercolesterolemia, hipertensão, entre outros. Mesmo assim, a maioria das espécies não apresenta estudo fitoquímico para determinação de atividades biológicas. Na bibliografia consultada terpenóides se apresentaram como compostos predominantes em Croton. O presente estudo foi realizado com a análise de óleos voláteis e de extratos metanólicos de folhas e caules de 10 amostras de Croton seção Lamprocroton Todas as espécies do estudo têm descrição química inédita. Foram identificados 44 compostos de óleos voláteis por CG/EM, sendo 14 monoterpenos e 30 sesquiterpenos. Alguns compostos oxigenados, importantes do ponto de vista de atividade biológica, ocorreram em altas concentrações, como 1,8-cineol (C. ericoides: 24,1%; C.linearifolius: 26,9%; C. muellerianus: 23,9%), linalol (C. dusenii: 18,2%), bisabolol (C. ceanothifolius: 49,9%), 1-isopropil-7-metil-4-metileno-1,3,4,6,8-hexa-hidro-2H-naftalen-4-ol (C. linearifolius: 25,2%; C. pallidulus var. pallidulus: 23,6%). Já no extrato metanólico foram identificados por CG/EM 15 diterpenos, 9 triterpenos e 13 esteróides. Grupo de metabólito secundário mais caracteristico de Croton, foram detectados 3 diterpenos de cadeia aberta (fitol, hexadecatetraenol e furanona), um diterpeno alcoólico (retinol), além de diterpenos com esqueleto tipo labdano, caurano, clerodano e podocarpano. Os dois clerodanos foram identificados com estrutura similar à trans-desidrocrotonina, composto com alto potencial farmacológico. Os podocarpanos até então registrados em apenas duas espécies de Croton foram comuns à Croton seção Lamprocroton, sendo identificados podocarp-7-en-3-ona 13β-metil-13-vinil, podocarp-7,8-diien-3-ona-13-acetoxi, ácido podocarpa-7,13-dien-15-óico e metil-13(2-metoxi-2-oxoetildeno)-14-metil-7-oxopodocarpan-15-oato, distribuídos em 5 espécies. Os triterpenos e esteróides apresentaram alta diversidade e foram detectados para todas as espécies do estudo, com especial atenção para os triterpenos α-amirina, lupeol e lupenona; e os esteróides β e γ-sitosterol, pelas altas concentrações e pelo potencial farmacológico. Os dados obtidos possibilitaram listagem de compostos e atividades com sugestões de direcionamento para futuros testes e desenvolvimentos farmacológicos. / Croton is a large genus of Euphorbiaceae comprising around 1.300 species, widespread in tropical and subtropical regions of America, Africa, Asia and Australia. Brazil is one of the main hot spot in the world, with more than 350 species described, many of them endemic. Although several species are used in tradicional medicine for the treatement of diseases like cancer, diabetes, fever, high cholesterol and high blood pressure. Most species have no phytochemical studies concerning their biological activities. Literature shows terpenoids as predominant secondary metabolite constituents in Croton. The present study was carried outwith the analysis of essential oils and crude methanolic extracts obtained from leaves and bark of 10 samples of Croton sect. Lamprocroton. All species used on this study were submitted to their first chemical description. Forty four compounds were identified on essential oil by GC/MS, 14 monoterpenes and 30 sesquiterpenes. Some oxygenated compounds with important biological activity were detectaed in high concentrations: 1,8-cineol (C. ericoides: 24.1%; C.linearifolius: 26.9%; C. muellerianus: 23.9%), linalol (C. dusenii: 18.2%), bisabolol (C. ceanothifolius: 49.9%), 1-isopropil-7-metil-4-metileno-1,3,4,6,8-hexa-hidro-2H-naftalen-4-ol (C. linearifolius: 25.2%; C. pallidulus var. pallidulus: 23.6%). The metanolic extract analysis reveled by GC/MS15 diterpenes, 9 triterpenes e 13 steroids. Diterpenes are describe as the main secondary metabolite in Croton. Besides diterpenes with labdan, cauran, clerodan and podocarpan skeletal types, three opened ring diterpenes (fitol, hexadecatetraenol e furanona) and one alcoholic diterpene (retinol) were detected. Two clerodans were identified with trans-desidrocrotonin estructure-like, a compound with high pharmacological use. Podocarpans that have only been registered for two Croton species, were commonly found on Croton sect. Lamprocroton (podocarp-7-en-3-one 13β-metil-13-vinil; podocarp-7,8-diien-3-one-13-acetoxi; podocarpa-7,13-dien-15-oic acid; and metil-13(2-metoxi-2-oxoetildeno)-14-metil-7-oxopodocarpan-15-oate). Triterpenes and steroids shown high diversity and were detected at all studied species, with a highlight for compounds with high pharmacological potencial like triterpens α-amirine, lupeol and lupenone; and the steroids beta and gamma-sitosterol. The results obtained led to a list of compounds and suggestions for future pharmacological tests and developments.
73

Synthèse totale d'un précurseur biomimétique des chalasines polycyliques et développement d'une méthodologie de photooxygénation bioinspirée / Total synthesis of a biomimetic precursor towards polycyclic chalasans and development of a bioinspired photoxygenation methodology

Laroche, Benjamin 03 October 2016 (has links)
Le phénomène d'oxygénation tardive des produits naturels a été investigué sur deux modèles d'études : les chalasines polycycliques et les diterpènes résiniques. Pour les chalasines, les cibles de synthèse envisagées étaient la trichoderone A et la trichodermone, deux chalasines d'origine fongique isolées récemment du champignon endophyte Trichoderma gamsii. En plus de leurs structures fascinantes, ces chalasines ont montré une inhibition modérée contre la lignée cellulaire tumorale humaine HeLa. Les études rétrosynthétiques de la trichoderone A et de la trichodermone, basées sur les hypothèses de biosynthèse des PKS-NRPS, ont dévoilé la possibilité d'un précurseur biomimétique commun par l'intermédiaire d'oxygénations bio-inspirées fréquentes in vivo. Ces travaux de thèse décrivent la synthèse totale de ce précurseur biosynthétique à travers le développement d'une nouvelle méthodologie de métathèse d'ényne cyclisante, suivie d'un réarrangement [3,3] d'Ireland-Claisen. La construction du squelette polycyclique repose sur une stratégie de Diels-Alder intramoléculaire, accédant ainsi au précurseur desiré. Des résultats préliminaires encourageants d'oxygénation bio-inspirées sont également décrits, en vue de l'accès vers les chalasines naturelles trichoderone A et trichodermone. Concernant les acides résiniques, une nouvelle méthodologie de photooxygénation bioinspirée a été développée. A l'aide d'un montage simple et efficace, des réactions de photooxygénations couplées à des réarrangements de Hock et de Kornblum-DeLaMare ont permis la formation de produits naturels ainsi que des molécules originales montrant des des activités antibactériennes prometteuses. / The late-stage oxygenation of natural products has been investigated on two studies templates: the polycyclic chalasans, the main topic of this thesis, and onto resinic diterpenes. Concerning the polycyclic chalasans, the envisaged synthetic targets were trichoderone A and trichodermone, two fungal secondary metabolites recently isolated from the endophytic fungus Trichoderma gamsii. In addition to their fascinating structures, these chalasans showed a moderate inhibition against human tumor HeLa cell line, which makes them very attractive for total synthesis. Based on the biosynthesis of PKS-NRPS compounds, the retrosynthetic studies of trichoderone A and trichodermone suggested the possibility of a common biomimetic precursor through bioinspired oxygenations frequently occurring in vivo. This thesis developed the total synthesis of this biomimetic precursor including the development of a new ring-closing enyne metathesis methodology, followed by a [3,3] Ireland-Claisen rearrangement. The construction of the polycyclic skeleton is based on an intramolecular Diels-Alder strategy, affording the desired precursor. Encouraging preliminary results have also been described towards the access to the natural chalasans trichoderone A and trichodermone, which have never been synthesized so far. On the subject of resinic diterpenes, a new bioinspired photooxygenation methodology has been developed. Thanks to a simple and efficient experimental set-up, photooxygenation reactions coupled with Hock and Kornblum-DeLaMare rearrangements allowed the formation of already isolated natural products, as well as novel molecules exhibiting promising antibacterial activities.
74

Enantiospecific Synthesis Of Guaianes And Tricyclic Ring Systems Of Elisabethins And Dumsins

Pardeshi, Vijendra H 07 1900 (has links) (PDF)
One area of natural product synthesis which has been heavily investigated in the last eight decades is the total synthesis of terpenoids. Among terpenoids, the presence of a great deal of stereochemical complexity in combination with a variety of functionalities makes sesquiterpenes challenging targets to the synthetic chemists. As a result synthetic activity in this area continues to flourish. The thesis entitled “Enantiospecific Synthesis of Guaianes and Tricyclic Ring Systems of Elisabethins and Dumsins’’ describes the studies directed towards the synthesis of the guaiane sesquiterpenes and exploratory studies towards elisabethins and dumsin diterpenoids. For convenience, the results are presented in two chapters; viz (1) Enantiospecific Total Synthesis of Guaiane Sesquiterpenes; and (2) Enantiospecific Synthesis of ABC Ring System of the Diterpenoids Elisabethins and Tetranortriterpenoids Dumsins. In each chapter of the thesis, the compounds are sequentially numbered (bold) and references are marked sequentially as superscripts and listed at the end of the chapter. All the spectra included in the thesis were obtained by xeroxing the original NMR spectra. Clavukerin A, the first member of the trisnorguaianes, was simultaneously isolated in 1983 by the research groups of Kitagawa from the Okinawan soft coral Clavularia koellikeri (stolonifer), and Bowden from the Australian soft coral Cespituloria sp. In 1992, Kakisawa and his research group reported the isolation of isoclavukerin A from the Okinawan soft coral Clavularia sp. In the present thesis, formal total syntheses of clavukerin A and isoclavukerin A have been described in the first part of the first chapter. To begin with, (R)-limonene has been transformed into 1-[5-isopropenyl-2-methylcyclopent-1-en-1-yl]pent-4-en-1-one via the 5-isopropenyl-2-methyl-cyclopent-1-en-1-carboxaldehyde. RCM reaction of the enone produced 6,10-dimethylbicyclo[5.3.0]deca-1(10),5-dien-2-one, which on epoxidation generated 1-[(1S,2S,5R) and (1R,2S,5S)-2-isopropenyl-5-methyl-6-oxabicyclo[3.1.0]hex-1yl]pent-4-en-1-ones. These epoxy ketones were then transformed into (6S,7S) and (6R,7S)6,10-dimethylbicyclo[5.3.0]dec-1(10)-en-2-ones, thus completing the formal total synthesis of clavukerin A and isoclavukerin A. In the subsequent parts of the first chapter, enantiospecific total syntheses of the guaiane sesquiterpenes, aciphyllenes A and B, isocalamusenone and 6-epiisocalamusenones, and (6S)- and (6R)-11-hydroxyguaiadienes have been described. Aciphyllene A was isolated in 1983 by Kubota and co-workers from the essential oil of the roots of Lindera glauca. Aciphyllene B was isolated by Konig et al. in 1998 from the liverwort D. hirusta. In 1979, Rohr and co-workers reported the isolation of isocalamusenone from the plant Acorus calamus L, In 2000, Nkunya and colleagues isolated (6R)-11-hydroxyguaiadiene from the root bark of Lettowianthus stellatus, whereas (6S)-11-hydroxyguaiadiene was isolated in 1977 by Bohlmann et al. from the roots of Parthenium hysterophorus. The 5isopropenyl-2-methyl-cyclopent-1-en-1-carboxaldehyde derived from (R)-limonene has been converted into the (3R,4S,6S,7S)- and (3R,4S,6R,7S)-3-acetyl-6,10 dimethylbicyclo[5.3.0]dec1(10)-en-4-ols employing a type II carbonyl ene reaction and Wilkinson’s hydrogenation as the key steps, which have been further converted into aciphyllenes A and B along with their C-6 epimers, (+)-isocalamusenone, 6-epi-isocalamusenone, and (6S)- and (6R)-11-hydroxyguaiadienes. In the second chapter of the thesis, enantiospecific synthesis of the ABC-ring systems of elisabethin group of diterpenoids and tetranortriterpenoids dumsins have been described, starting from the readily available monoterpene (R)-carvone. To begin with, (R)-carvone has been transformed into 1,6,6-triallylcarveol, which on two simultaneous RCM reactions generated the ABC-ring system of the elisabethin group of diterpenoids. An alternative synthetic strategy was also developed for the same compound. Thus, first (R)-carvone has been transformed into 6-allyl-10-isopropenyl-7-methylspiro[4.5]deca-2,7-dien-6-ol, which on ROM-RCM reaction generated the requisite tricyclic alcohol, which on oxidation generated 4,8-dimethyltricyclo[7.4.0.01,5]trideca-3,8,11-trien-7-one, which represents the ABC ring system of elisabethins. Introduction of the second allyl group at the C-7 position of 6-allyl-10isopropenyl-7-methylspiro[4.5]deca-2,6-dien-8-one followed by RCM reaction resulted in the formation of the tricyclic ketones (1S,4S,6R) and (1R,4S,6R)-4-isopropenyl-1-methylbicyclo[4.4.0]decanespiro[5,1']-cyclopenta-3',8-diene-2-ones, which represents the ABC ring system of tetranortriterpenoids dumsins.
75

Enantiospecific Synthesis Of Tetraquinane Diterpenes Crinipellins

Gowri, V 09 1900 (has links) (PDF)
Among Nature's creation, terpenoids are more versatile and exciting compounds, and provide fertile ground for developing and testing new synthetic strategies because of their phenomenal structural diversity. The thesis entitled “Enantiospecific Synthesis of Tetraquinane Diterpenes Crinipellins” describes the first enantiospecific synthesis of norcrinipellin and crinipellins, and the tricyclic core structure of tricycloillicinone, ialibinones, and takaneones. In the thesis, the compounds are sequentially numbered (bold) and references are marked sequentially as superscripts and listed at the end of the thesis. All the spectra included in the thesis were obtained by xeroxing the original NMR spectra. Crinipellins, the first group of natural products to contain a tetraquinane carbon framework, were isolated in 1985 by the research groups of Steglich and Anke from the submerged cultures of the basidiomycete Crinipellis stipitaria. Recently, In 2010, Shen and Li also reported the isolation of four new crinipellins from the Crinipellis stipitaria 113. In the present thesis, first enantiospecific synthesis of norcrinipellin and crinipellins has been described. To begin with, (S)-campholenaldehyde was transformed into the (1R,5R)-7,8,8-trimethylbicyclo[3.3.0]oct-6-en-3-one employing an intramolecular rhodium carbenoid insertion of a diazoketone, which was then transformed into the methyl (1R,2S,6R,8S,10R)-10-methoxy-2-methyl-5-oxotricyclo[6.3.0.02,6]undecane-4-carboxylate via rhodium carbenoid promoted activation of a tertiary methyl group to generate the cis, anti, cis-linear triquinane. The triquinane obtained was then transformed into ethyl 4-[(1R,2S,6S,8S,10R)-10-methoxy-2,5dimethyl-3-oxotricyclo[6.3.0.02,6]undec-4-ene-6-yl]butanoate by a sequence of reactions including an alkylative 1,3-enone transposition, which on intramolecular Michael addition reaction followed by DBU mediated equilibration generated a 5:4 mixture of ethyl (1S,3S,5R,7R,8S,11S,12R) and (1S,3S,5R,7R,8S,11S,12S)-5-methoxy8,11-dimethyl-9-oxotetracyclo[6.6.0.01,11.03,7]tetradecane-12-carboxylates, which were transformed into (12R) and (12S)-15-hydroxy-5-methoxy-20-norcrinipellin-9-ones and (12S) and (12R)-5-methoxy-20-norcrinipell-15-en-9-ones. The methodology has been further modified and extended for the first enantiospecific synthesis of (12R) and (12S) 15-hydroxy-5-(methoxymethoxy)crinipellin-9-ones In 1995, Fukuyama and coworkers reported the isolation of tricycloillicinone from Illicium tashiroi, containing an interesting 3,4,4-trimethyltricyclo[5.3.1.01,5]undecane system. This tricyclic structure was also present in two groups of acylphloroglucinoid natural products, ialibinones and takaneones. An enantiospecific synthesis of the tricyclic core structure of tricycloillicinone, ialibinones, and takaneones have been accomplished starting from (S)-campholenaldehyde employing a transannular RCM reaction as the key step, (S)-Campholenaldehyde was converted into methyl (5R)-6,6,7-trimethyl-3-oxobicyclo[3.3.0]octa-1,7-diene-2-carboxylate via the methyl (1R,5R)-6,6,7-trimethyl-3-oxobicyclo[3.3.0]oct-7-ene-2-carboxylate, which was then transformed into (1R,3S,5S)-3-allyl-7,8,8-trimethyl-5-vinylbicyclo[3.3.0]oct6-en-3-ol containing the vinyl and allyl groups at C-1 and C-3 carbons syn to each other. Transannular RCM reaction of the hydroxy diene led to the tricyclic core structure of tricycloillicinone. Further elaboration of the side chain at C-3 position led to the tricyclic core structure of ialibinones, and takaneones.
76

Diversité chimique et potentialités antivirales d'Euphorbiacées tropicales / Chemical diversity and antiviral potential of tropical Euphorbiaceae

Remy, Simon 23 October 2019 (has links)
Dans le but d'identifier de nouveaux inhibiteurs du chikungunya (CHIKV), de la dengue (DENV) et de la zika (ZIKV), une étude systématique portant sur 339 extraits d'Euphorbiaceae tropicales a été réalisée grâce à un test cellulaire d'inhibition du CHIKV et à des tests d'inhibition de l'ARN-polymérase de DENV et ZIKV.Sandwithia guyanensis et Sagotia racemosa, deux espèces provenant de Guyane française, dont les extraits d'écorce présentaient une forte activité anti-CHIKV importante, ont d'abord été étudiées. À la suite d'un processus d'isolement bioguidé classique, plus de 20 nouveaux diterpènes ont été caractérisés, mais aucun d'entre eux ne présentait une activité antivirale significative. Pour résoudre ce problème, des réseaux moléculaires (MN) ont été construits grâce aux données de LC-MS/MS obtenues à partir des fractions chromatographiques des deux extraits. L'annotation des MN, a permis l'identification d'analogues du phorbol, connus pour être de puissants inhibiteurs du CHIKV. Présents à l'état de traces, ces composés fournissent une explication plausible à l'activité anti-CHIKV des deux extraits.Dans une deuxième étude, une stratégie de priorisation des extraits de plantes basée sur la fusion de données taxonomiques et d'essais biologiques au sein d'un MN a conduit à l'isolement et à la caractérisation ciblée de plusieurs inhibiteurs doubles de Codiaeum peltatum. Les deux études illustrent comment les MN et les progrès récents en matière d'annotation des données de LC-MS/MS peuvent être mis en œuvre dans les études phytochimiques pour améliorer le processus découverte de composés bioactifs. / In order to identify new inhibitors of chikungunya (CHIKV), dengue fever (DENV) and zika (ZIKV), systematic study with 339 extracts from tropical Euphorbiaceae species was performed in a virus-cell-based assay for CHIKV and DENV and ZIKA NS5 inhibition assaysThe French Guianese species Sandwithia guyanensis and Sagotia racemosa, from which bark extracts exhibited significant anti-CHIKV activities, were first investigated. Following a classical bioguided isolation workflow, more than 20 new diterpenes were characterized but none of them showed significant antiviral activity. To adress this issue, molecular networks (MN) were built from the LC-MS/MS data acquired from the chromatographic fractions of both extracts. The annotation of the MNs led to the identification of phorbol analogues, known to be potent CHIKV inhibitors. Present at trace levels, these compounds provide a plausible explanation for the anti-CHIKV activity of both extracts.In a second study, a strategy to prioritize plant extracts based on the fusion of taxonomic data and bioassays within a MN led to the isolation and targeted characterization of several dual inhibitors from Codiaeum peltatum. Both studies illustrate how MN and recent advances in LC-MS/MS data annotation can be implemented in phytochemical studies to improve the bioactive compounds discovery process.
77

Development of a capillary electrophoretic method for the separation and detection of resin acids

Rigby, Tracey. January 2000 (has links)
No description available.
78

Atividade antiinflamatória, toxicidade e fitoquímica do óleo-resina de copaíba, proveniente de diferentes espécies, e de suas respectivas frações (OU) Atividade antiinflamatória, toxicidade e aspectos químicos do óleo-resina de Copaíba, proveniente de diferentes espécies, e de suas frações / Anti-inflamatory activity, toxicity and chemical composition of Copaifera oils, from different species, and theirs fractions

Rio, Ricardo Gomide Woisky Do 01 June 2001 (has links)
Espécies do gênero Copaifera (Leguminosae) são nativas de regiões tropicais da América Latina e África. No Brasil, seu óleo-resina é amplamente utilizado em medicina popular como antiinflamatório, antisséptico e cicatrizante. No presente trabalho, avaliou-se, em uma primeira fase, a atividade antiinflamatória em modelo experimental agudo das seguintes amostras de óleo-resina: comercial, gentilmente cedida pela empresa Pronatus, Copaifera reticulata, C. multijuga e C. paupera. As amostras foram administradas pela via oral, sendo selecionada, das amostras identificadas botanicamente, a C. reticulata por apresentarem maior atividade. A amostra comercial também foi ensaiada no modelo experimental acima. Os óleo-resinas foram analisados por cromatografia gasosa acoplada à espectrometria de massas tendo revelado a presença de sesquiterpenos e diterpenos. Foram identificados vinte e dois compostos na amostra comercial e vinte seis na amostra de C. reticulata. Deste total, seis substâncias foram comuns a ambas as amostras. A seguir, os óleos-resinas foram destilados e separadas suas respectivas frações sesqui e diterpênicas. Tanto os óleos-resinas quanto suas frações foram avaliados farmacologicamente. As atividades farmacológicas testadas foram: atividade antiinflamatória aguda, subcrônica, crônica e ensaios de toxicidade aguda, subcrônica e citotoxicidade. A atividade antiinflamatória foi testada em cinco modelos: edema de pata induzido pela carragenina, nistatina e miconazol; indução de formação de tecido granulomatoso e dermatite induzida pelo óleo de cróton. Nos modelos utilizados as doses testadas foram de 2,47 ml/kg (DE50 no modelo da carragenina) para a amostra comercial e suas frações sesqui e diterpênicas e 2,02 ml/kg (Dose equipotente no modelo da carragenina) para a amostra de C. reticulata e suas frações sesqui e diterpênicas). Em todos os ensaios realizados com as amostras, evidenciaram-se intensa atividade antiflogística, com exceção da C. reticulata que apresentou elevada toxicidade no modelo de indução do tecido granulomatoso. Nos ensaios de toxicidade aguda, a amostra C. reticulata (DL50 = 4,48 ml/kg) apresentou toxicidade maior que a amostra comercial (DL50 > 12,35 ml/kg). Suas frações sesquiterpênicas foram bem menos tóxicas que seus correspondentes óleos-resinas com DL50 maiores que 9,14 e 20 ml/kg, respectivamente para C. reticulata e amostra comercial: Por outro lado, a fração resinosa (diterpênica) apresentou alta toxicidade com DL50 superiores a 2,85 e 1,29 ml/kg, respectivamente para a amostra comercial e C. reticulata. Nos ensaios de toxicidade subcrônica confirmou-se a toxicidade menor para a fração sesquiterpênica da amostra de C. reticulata. O óleo-resina de C. reticulata apresentou toxicidade renal e alterações hepáticas indicando que pode haver um comprometimento hepático. / Species of the genus Copaifera (Leguminosae) are native of tropical regions in Latin America and Africa. In Brazil, its oil-resin is widely utilized in popular medicine as anti-inflammatory, antiseptic and cicatrizing medicine. In the present work, we initially evaluated the acute anti-inflammatory activity of the following samples: commercial, Copaifera reticulata, C. multijuga and C. paupera. All the samples were administered by oral route. This initial pharmacological evaluation revealed that the C. reticulata was clearly more effective. In the second part of this work, the C. reticulata and the commercial samples, kindly provided by Pronatus-Manaus, were investigated. The oil-resins of the selected samples were analyzed by gas chromatography connected with mass spectrometry, revealing the presence of sesquiterpens and diterpens. Twenty two compounds in the commercial sample and twenty six in the C. reticulata were identified. Then after, the oil-resins were distilled and separated in their respective sesqui and diterpens fractions. Both oil-resins and their fractions were pharmacologically evaluated. The pharmacological evaluations were: acute, sub-chronic and chronic anti-inflammatory activities and acute, sub-chronic toxicities and cito-toxicities assays. The anti-inflammatory activity was studied in five experimental models: carrageenan, nistatin and miconazole paw oedema; induction of granulomatous tissue formation and croton oil dermatitis. The administered doses by oral route were 2.47 ml/kg (EQ50 for carrageenan model) to commercial sample and its sesqui and diterpens fractions, and 2.02 ml/kg to C. reticulata sample and its sesqui and diterpens fractions. All the assays carried out with the selected samples showed intense anti-flogistic activity, except for C. reticulata that exhibited high toxicity in the granulomatous tissue model. In the acute toxicity studies, C. reticulata (LD50 = 4.48 ml/kg) revealed greater toxicity in comparison with the commercial sample (LD50 > 12.35 ml/kg). Its sesquiterpens fractions were less toxic that its correspondent oil-resins with LD50 higher than 9.14 and 20 m1/kg, for C. reticulata and commercial sample, respectively. On the other hand, resin fraction (diterpenic) presented high toxicity with LD50 higher than 2.85 and 1.29 ml/kg for commercial and C. reticulata samples, respectively. The sub-chronic assays, confirmed the less toxicity for the C. reticulta sesquiterpenic fraction. The C. reticulata oil-resin presented renal toxicity and hepatics alterations.
79

Model study and partial synthesis of prehispanolone and derivatives from hispanolone.

January 1994 (has links)
En Si Wang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 126-140 (2nd gp.)). / Acknowledgements --- p.i / Contents --- p.ii / Abstract --- p.iv / List of Acronyms and Abbreviations --- p.vi / introduction --- p.1 / Chapter I. --- "Platelet Activating Factor (PAF)´ؤPast, Present, and Future" --- p.1 / Chapter I-1. --- What is PAF? --- p.1 / Chapter I-2. --- Biochemistry of PAF --- p.2 / Chapter I-2-1. --- Metabolic Cycle of PAF --- p.3 / Chapter I-2-1-A. --- Biosynthesis of PAF --- p.4 / Chapter I-2-1 -B. --- Inactivation of PAF --- p.6 / Chapter I-2-2. --- Role of Endogenous PAF in Cell --- p.7 / Chapter I-3. --- Chemistry of PAF --- p.8 / Chapter I-4. --- Pathobiology of PAF --- p.9 / Chapter II. --- PAF Receptor --- p.10 / Chapter II-1. --- Presence and Characteristics of PAF Receptor --- p.10 / Chapter II-l-l. --- Solubilization of PAF Receptor --- p.10 / Chapter II-1-2. --- G-Protein Involvement --- p.11 / Chapter II-1-3. --- Species Differences --- p.11 / Chapter II-1-4. --- Multiple Conformational States of PAF Receptor --- p.12 / Chapter II-1-5. --- PAF Receptor Heterogeneity --- p.12 / Chapter II-2. --- Putative Conformation of PAF Membrane Binding Sites --- p.13 / Chapter II-3. --- Recent Progress in PAF Receptor Research --- p.15 / Chapter III. --- PAF Receptor Antagonist --- p.18 / Chapter III-1. --- Classification of PAF Antagonists --- p.18 / Chapter III-2. --- Inhibition Types of PAF Receptor Antagonists --- p.19 / Chapter III-2-1. --- Nonspecific Inhibition of the Effects of PAF --- p.21 / Chapter III-2-2. --- Specific Inhibition of PAF --- p.22 / Chapter III-3. --- Recent Progress in PAF Receptor Antagonist Research --- p.22 / Chapter IV. --- Pharmacology and Syntheses of Spiro-Ether Structural Units --- p.26 / Chapter IV-1. --- Natural Products Containing Spiro-Ether and Related Structural Units --- p.30 / Chapter IV-1-1. --- Labdane Diterpenoids Containing Spiro-Ether Structural Units --- p.30 / Chapter IV-1-2. --- Leucodrin and Related Derivatives --- p.32 / Chapter IV-2. --- Synthetic Methods of Spiro-Ethers and Related Derivatives --- p.34 / Chapter V. --- Aim of the Present Work --- p.45 / RESULTS AND DISCUSSION --- p.47 / Chapter I. --- Isolation and Structure Elucidation of Prehispanolone (1) and Preleoheterin (3) --- p.47 / Chapter I-1. --- Material and Isolation --- p.47 / Chapter I-2. --- Structure Elucidation of Prehispanolone (1) and Preleoheterin (3) --- p.47 / Chapter II. --- Synthesis of Model Compounds --- p.53 / Chapter II-l. --- "Synthesis of 2-Methyl-1,7-dioxaspiro[4.4]nonane (137)" --- p.53 / Chapter II-2. --- "Synthesis of 2,2-Dimethyl-l,7-dioxaspiro[4.4]nonane (139)" --- p.68 / Chapter II-3. --- "Synthesis of 2,2-Diphenyl-1,7-dioxaspiro[4.4]nonane (141) and 2,2-Diphenyl-l,7-dioxaspiro[4.4]non-8-ene (142)" --- p.72 / Chapter III. --- "Partial Synthesis of 13R, 14,15-Dihydroprehispanolone (5),13S,14,15-Di- hydroprehispanolone (135) and prehispanolone (1)" --- p.76 / CONCLUSION --- p.89 / EXPERIMENTAL SECTION --- p.91 / REFERENCES --- p.126 / APPENDIX --- p.141
80

Atividade antiinflamatória, toxicidade e fitoquímica do óleo-resina de copaíba, proveniente de diferentes espécies, e de suas respectivas frações (OU) Atividade antiinflamatória, toxicidade e aspectos químicos do óleo-resina de Copaíba, proveniente de diferentes espécies, e de suas frações / Anti-inflamatory activity, toxicity and chemical composition of Copaifera oils, from different species, and theirs fractions

Ricardo Gomide Woisky Do Rio 01 June 2001 (has links)
Espécies do gênero Copaifera (Leguminosae) são nativas de regiões tropicais da América Latina e África. No Brasil, seu óleo-resina é amplamente utilizado em medicina popular como antiinflamatório, antisséptico e cicatrizante. No presente trabalho, avaliou-se, em uma primeira fase, a atividade antiinflamatória em modelo experimental agudo das seguintes amostras de óleo-resina: comercial, gentilmente cedida pela empresa Pronatus, Copaifera reticulata, C. multijuga e C. paupera. As amostras foram administradas pela via oral, sendo selecionada, das amostras identificadas botanicamente, a C. reticulata por apresentarem maior atividade. A amostra comercial também foi ensaiada no modelo experimental acima. Os óleo-resinas foram analisados por cromatografia gasosa acoplada à espectrometria de massas tendo revelado a presença de sesquiterpenos e diterpenos. Foram identificados vinte e dois compostos na amostra comercial e vinte seis na amostra de C. reticulata. Deste total, seis substâncias foram comuns a ambas as amostras. A seguir, os óleos-resinas foram destilados e separadas suas respectivas frações sesqui e diterpênicas. Tanto os óleos-resinas quanto suas frações foram avaliados farmacologicamente. As atividades farmacológicas testadas foram: atividade antiinflamatória aguda, subcrônica, crônica e ensaios de toxicidade aguda, subcrônica e citotoxicidade. A atividade antiinflamatória foi testada em cinco modelos: edema de pata induzido pela carragenina, nistatina e miconazol; indução de formação de tecido granulomatoso e dermatite induzida pelo óleo de cróton. Nos modelos utilizados as doses testadas foram de 2,47 ml/kg (DE50 no modelo da carragenina) para a amostra comercial e suas frações sesqui e diterpênicas e 2,02 ml/kg (Dose equipotente no modelo da carragenina) para a amostra de C. reticulata e suas frações sesqui e diterpênicas). Em todos os ensaios realizados com as amostras, evidenciaram-se intensa atividade antiflogística, com exceção da C. reticulata que apresentou elevada toxicidade no modelo de indução do tecido granulomatoso. Nos ensaios de toxicidade aguda, a amostra C. reticulata (DL50 = 4,48 ml/kg) apresentou toxicidade maior que a amostra comercial (DL50 > 12,35 ml/kg). Suas frações sesquiterpênicas foram bem menos tóxicas que seus correspondentes óleos-resinas com DL50 maiores que 9,14 e 20 ml/kg, respectivamente para C. reticulata e amostra comercial: Por outro lado, a fração resinosa (diterpênica) apresentou alta toxicidade com DL50 superiores a 2,85 e 1,29 ml/kg, respectivamente para a amostra comercial e C. reticulata. Nos ensaios de toxicidade subcrônica confirmou-se a toxicidade menor para a fração sesquiterpênica da amostra de C. reticulata. O óleo-resina de C. reticulata apresentou toxicidade renal e alterações hepáticas indicando que pode haver um comprometimento hepático. / Species of the genus Copaifera (Leguminosae) are native of tropical regions in Latin America and Africa. In Brazil, its oil-resin is widely utilized in popular medicine as anti-inflammatory, antiseptic and cicatrizing medicine. In the present work, we initially evaluated the acute anti-inflammatory activity of the following samples: commercial, Copaifera reticulata, C. multijuga and C. paupera. All the samples were administered by oral route. This initial pharmacological evaluation revealed that the C. reticulata was clearly more effective. In the second part of this work, the C. reticulata and the commercial samples, kindly provided by Pronatus-Manaus, were investigated. The oil-resins of the selected samples were analyzed by gas chromatography connected with mass spectrometry, revealing the presence of sesquiterpens and diterpens. Twenty two compounds in the commercial sample and twenty six in the C. reticulata were identified. Then after, the oil-resins were distilled and separated in their respective sesqui and diterpens fractions. Both oil-resins and their fractions were pharmacologically evaluated. The pharmacological evaluations were: acute, sub-chronic and chronic anti-inflammatory activities and acute, sub-chronic toxicities and cito-toxicities assays. The anti-inflammatory activity was studied in five experimental models: carrageenan, nistatin and miconazole paw oedema; induction of granulomatous tissue formation and croton oil dermatitis. The administered doses by oral route were 2.47 ml/kg (EQ50 for carrageenan model) to commercial sample and its sesqui and diterpens fractions, and 2.02 ml/kg to C. reticulata sample and its sesqui and diterpens fractions. All the assays carried out with the selected samples showed intense anti-flogistic activity, except for C. reticulata that exhibited high toxicity in the granulomatous tissue model. In the acute toxicity studies, C. reticulata (LD50 = 4.48 ml/kg) revealed greater toxicity in comparison with the commercial sample (LD50 > 12.35 ml/kg). Its sesquiterpens fractions were less toxic that its correspondent oil-resins with LD50 higher than 9.14 and 20 m1/kg, for C. reticulata and commercial sample, respectively. On the other hand, resin fraction (diterpenic) presented high toxicity with LD50 higher than 2.85 and 1.29 ml/kg for commercial and C. reticulata samples, respectively. The sub-chronic assays, confirmed the less toxicity for the C. reticulta sesquiterpenic fraction. The C. reticulata oil-resin presented renal toxicity and hepatics alterations.

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