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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.
51

Atividades biológicas de terpenos de óleos de copaíba (Copaifera spp. – Fabaceae)

Vargas, Fabiano de Sousa 30 August 2013 (has links)
Submitted by Alisson Mota (alisson.davidbeckam@gmail.com) on 2015-07-21T20:23:22Z No. of bitstreams: 1 Dissertação - Fabiano de Sousa Vargas.pdf: 3768449 bytes, checksum: fcc3a57e9e6cbb1e79933d1feba3250c (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-23T18:52:43Z (GMT) No. of bitstreams: 1 Dissertação - Fabiano de Sousa Vargas.pdf: 3768449 bytes, checksum: fcc3a57e9e6cbb1e79933d1feba3250c (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-23T18:56:54Z (GMT) No. of bitstreams: 1 Dissertação - Fabiano de Sousa Vargas.pdf: 3768449 bytes, checksum: fcc3a57e9e6cbb1e79933d1feba3250c (MD5) / Made available in DSpace on 2015-07-23T18:56:54Z (GMT). No. of bitstreams: 1 Dissertação - Fabiano de Sousa Vargas.pdf: 3768449 bytes, checksum: fcc3a57e9e6cbb1e79933d1feba3250c (MD5) Previous issue date: 2013-08-30 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / Copaíba ( Copaifera L. ) is one of the best known and Amazonian plants used by traditional populations in natural medicine . The oleoresin of copaiba is a source of terpene compounds. The previous fractionation of terpene acids contained copaiba oil for the isolation of metabolites of interest is a useful method in dispatch processes phytochemicals later. The use of ion exchange chromatography is an alternative that minimizes the inconvenience of the formation of emulsions difficult separation. This paper proposes the use of methodology by ion exchange chromatography silica treated with aqueous KOH in order to re-isolate constituent terpenoids acids present in oleoresin gender Copaifera L quantity that allows making various biological assays. Aspects of the anti-inflammatory activity and antitumor activity via biological assays, enzymatic assays being developed tests (inhibition of tyrosinase and lipoxygenase) of cytokine and cytotoxicity in model cell culture in order to get a new bioactive compound that can be used in the preparation of a phytochemical or phyto, such as bleaching or skin protectors. Were obtained and identified by spectroscopic and spectrometric methods six (06) diterpene acids: copalic, 3-hydroxy-copalic, 3-acetoxy-copalic, hardwíckiico, colávico-15-methyl ester and kaurenoic. The acid 3-hydroxy-copalic was capable of inhibiting tyrosinase enzyme with IC50=255.53 ±18.59 μM . The colávico-15-methyl ester showed a higher capacity to inhibit lipoxygenase enzyme (IC50=157.82 ±17.69 μM ) . The cytotoxic activity of the substances was evaluated in healthy cells by strains of human lymphocytes , fibroblasts and 3T3L1 murine J774 macrophages , which poisonous substances only at concentrations above 250 μM . Was also made of the APPRAISAL hemolytic potential of the compounds , and found that none had significant hemolytic activity at concentrations up to 50 mM . For lines AGP - 1 ( gastric cancer ) , HCT -116 (colon cancer) , MCF - 7 ( breast cancer) , NIHOVCAR ( ovarian cancer ) , SKAMELL - 4 ( melanoma ) and SF -295 ( human glioblastoma ) , tested at a single concentration of 20 μM , showed no significant changes in cell viability . The antiinflammatory activity of the compounds was evaluated as inhibition of NO production in murine J774 macrophage lineage stimulated with LPS where the copalic acid ( 98.48 ± 1.30 % ) and hardwickiico acid ( 92.73 ± 4.97% ) had activity equivalent to that of standard indomethacin ( 96.58 ± 1.7 % ) at concentration of 100 μM . Was investigated first the effect of compounds isolated diterpene acids on the production of TNF - α , IL -6 and IL-10. The compounds did not inhibit the production of TNF - α . The acid 3-acetoxy-copalic, kaurenoic , colávico-15-methyl ester and copalic inhibited the production of IL -6 23.84 ± 8.17 %, 11.21 ± 5.74 %, 17.34 ± 4 18 ± 1.86 % and 4.19 %, respectively, at a single concentration of 50 μM . The kaurenoic acid , 3- acetoxy - copalic copalic and induced the production of IL-10 at concentrations of 12.5 μM and 25 μM , but there was a decrease in this induction when tested at a concentration of 50 μM . The kolávic-15-methyl ester and hardwickiic acid no changes of IL -10. Thus, these diterpenes may be considered components responsible for contributing to combat inflammation, however it is necessary to develop a pharmaceutical probably topical, to conduct clinical trials aimed to demonstrate its application in the treatment of injuries acute and chronic skin. / A copaíba (Copaifera L.) é uma das plantas amazônicas mais conhecidas e utilizadas por populações tradicionais como medicamento natural. O óleo-resina de copaíba é fonte de compostos terpênicos. O fracionamento prévio dos ácidos terpênicos contidos óleo de copaíba para o isolamento de metabólitos de interesse é um método útil na celeridade dos processos fitoquímicos posteriores. A utilização da cromatografia de troca iônica é uma alternativa que minimiza o inconveniente da formação de emulsões de difícil separação. O presente trabalho propõe o uso de metodologia de cromatografia por troca iônica por sílica tratada com solução aquosa de KOH com o objetivo de re-isolar constituintes ácidos terpenoides presentes em óleo-resinas do gênero Copaifera L em quantidade que permita a realização de diversos ensaios biológicos. Foram abordados aspectos da atividade anti-inflamatória e antitumoral, por meio de ensaios biológicos, sendo desenvolvidos ensaios enzimáticos (testes de inibição da tirosinase e lipoxigenase), de dosagem de citocinas e de modelo de citotoxicidade em cultura de células, a fim de obter-se um novo composto bioativo que poderá ser utilizado na elaboração de um fitofármaco ou fitocosmético, tais como clareadores ou protetores de pele. Foram obtidos e identificados por métodos de espectroscopia e espectrometria, seis (06) ácidos diterpênicos: os ácidos copálico, 3-hidróxi-copálico, 3-acetóxi-copálico, hardwíckiico, colávico-15-metil éster e o caurenóico. Apenas o ácido 3-OH-copálico apresentou capacidade de inibição da enzima tirosinase com CI50 de 255,53 ±18,59 μM. O colávico-15-metil éster apresentou maior capacidade de inibição da enzima lipoxigenase (CI50 = 157,82 ±17,69 μM). As atividades citotoxicas das substâncias foram avaliadas em células saudáveis por linhagens de linfócitos humanos, fibroblastos murinos 3T3L1 e macrófagos J774, sendo as substancias tóxicas apenas em concentrações acima de 250 μM. Foi feita também a avalição do potencial hemolítico dos compostos, sendo verificado que nenhum apresentou atividade hemolítica significativa em concentrações de até 50 mM. Para as linhagens AGP-1 (câncer gástrico), HCT-116 (cólon retal), MCF-7 (câncer de mama), NIHOVCAR (câncer de ovário), SKAMELL-4 (melanona) e SF-295 (glioblastoma humano), testadas em concentração única de 20 μM, não apresentaram alterações significativas da viabilidade celular. A atividade antiinflamatoria dos compostos foi avaliada quanto à inibição da produção de NO na linhagem de macrófagos murinos J774 estimulados com LPS, onde o ácido copálico (98,48±1,30%) e o ácido hardwickiico (92,73±4,97%) tiveram atividade equivalente ao do padrão indometacina (96,58±1,7%), todos na concentração de 100 μM. Foi investigada pela primeira vez a influência de compostos ácidos diterpênicos isolados sobre a produção de citocina TNF-α, IL-6 e IL-10. Os compostos não inibiram a produção de TNF-α. Os ácidos 3-acetóxi-copálico, caurenóico, colávico-15-metil éster e o copálico inibiram a produção de IL-6 em 23,84±8,17%; 11,21±5,74%; 17,34±4,18% e 4,19±1,86%, respectivamente, na concentração única de 50 μM. Os ácidos caurenóico, 3-acetóxi-copálico e copálico induziram a produção de IL-10 em concentrações entre 12,5 μM e 25 μM, porém houve uma diminuição nessa indução quando testados na concentração de 50 μM. Para os ácidos colávico-15-metil éster e o hardwickiico não houve alterações da produção de IL-10. Com isso, esses diterpenos podem ser considerados componentes responsáveis por contribuir no combate ao processo inflamatório, no entanto faz-se necessário o desenvolvimento de uma formulação farmacêutica, provavelmente de uso tópico, para realização de ensaios clínicos visando comprovar a sua aplicação no tratamento de lesões de pele agudas e crônicas.
52

Terpenos de Wunderlichia crulsiana e Mikania sp. nov. / Terpenes from Wunderlichia crulsiana and Mikania sp. nov.

Cecilia Verónica Nuñez 19 May 2000 (has links)
A presente tese relata o estudo químico de duas espécies vegetais pertencentes à família Asteraceae: Mikania sp. nov; e Wunderlichia crulsiana. Da espécie Mikania sp. nov. foram estudados os extratos diclorometânicos das folhas e dos galhos, tendo sido isolados e identificados sete ácidos diterpênicos; dos óleos voláteis das folhas e dos galhos foram identificadas vinte substâncias entre monoterpenos e sesquiterpenos. Da espécie Wunderlichia crulsiana foram estudados os extratos diclorometânicos das flores e dos galhos. Das flores foram isolados e identificados palmitatos e acetatos de triterpenoílas. Dos galhos foram isolados e identificados acetatos de triterpenoílas e triterpenonas e identificados por CG triterpenóis acetilados e palmitatos de triterpenoílas hidrolisados e posteriormente acetilados. Deste extrato foram também isolados e identificados três lactonas sesquiterpênicas e um sesquiterpeno. A identificação das substâncias foi realizada através de RMN de 1H, de 13C (BBD e DEPT 135º), CG/EM e co-injeção de padrões. Os extratos brutos de ambas as plantas apresentaram discreta atividade, quando submetidos a um ensaio antifúngico. As frações, contendo os triterpenóis, acetatos e palmitatos de triterpenoflas e as lactonas sesquiterpênicas, foram testadas quanto à atividade anti-infíamatória mostrando-se bastante ativas. Tanto os extratos brutos quanto as fraqões supracitadas não se mostraram ativos em um ensaio antitumoral. Estes resultados indicam a seletividade da atividade dos extratos e frações, possivelmente não contendo substâncias citotóxicas. / This work describes the chemical study of two plants which belong to the family Asteraceae: Mikania sp. nov. and Wunderlichia crulsiana. The dichlorometane extracts from leaves and stems of Mikania sp. nov. we studied and seven diterpenic acids were isolated and identified. The volatile oil from leaves and stems of this plant were also studied and twenty substances among monoterpenes and sesquiterpenes were identified. From Wunderlichia crulsiana we analysed the dichlorometane extracts from flowers and stems. From flowers we isolated and identified triterpenes esterified with palmitic acid and acetic acid. From stems we isolated and identified triterpenes esterified with acetic acid and 3-oxo-triterpenes. By GC, we identified hydroxylated triterpenes that were acetylated, and triterpenes esterified with palmitic acid that were hydrolysed and acetylated. From stems we also isolated and identified three sesquiterpene lactones and a sesquiterpene. The compounds were identified by PMR, CMR (BBD and DEIT 135º), GC/MS and co-injection with authentic samples The extracts of both plants showed low activity when submitted to bioassay with Cladosporium sphaerospermum. The fractions which contain the hydroxylated triterpenes, triterpenes esterified with acetic and palmitic acids and sesquiterpene lactones were submitted to anti-inflammatory bioassay and showed 42%, 29%, 29% and 47% of activity, respectively. The above mentioned extracts and the fractions did not show significant activity on the Saccharomyces cerevisae bioassay, so there were not citotoxic substances in them.
53

Untersuchung ausgewählter Inhaltsstoffe in Kaffee und Kaffeezubereitungen

Buchmann-Hempel, Sandra 26 February 2024 (has links)
Kaffee ist seit vielen Jahren das beliebteste Getränk der Deutschen. Im Handel wird Kaffee auf mannigfaltige Art angeboten z.B. als Röstkaffee, Instantkaffee oder auch als Bestandteil von anderen Getränken. Eingesetzt werden fast ausschließlich die Kaffee Arten Coffea arabica und Coffea canephora var. Robusta, dabei wird Arabica Kaffee fast doppelt so teuer gehandelt wie Robusta-Kaffee. Werden Kaffees als „100 % Arabica“ ausgelobt, so sollten auch solche Bohnen zu 100 % enthalten sein. Mit dieser Dissertation ist es gelungen, erstmalig mit einer Schnellmethode Robustazumischungen zu Arabica-Kaffee über die 16 OMC Ester zu bestimmen. Außerdem konnte die Analytik der schwierigen Matrix Instantkaffee wesentlich verbessert werden. Weiterhin konnte gezeigt werden, dass durch die Veränderungen der Einstellungen an einem Kaffeeautomaten die Cafestolgehalte im Espresso drastisch reduziert werden können und so das Risiko deutlich minimiert wird, an koronaren Herzerkrankungen zu erkranken. Weiterhin wurde die Sterolfraktion von Roh und Röstkaffees untersucht, dabei wurden erstmalig Sterolglucoside für Kaffee beschrieben. In einem weiteren Abschnitt wurden Milchmischgetränke mit Kaffeezusatz untersucht, um den wertgebenden Inhaltsstoff Kaffee zu quantifizieren.
54

Structure elucidation of bioactive natural products from Madagascar marine algae and cyanobacteria

Andrianasolo, Eric Hajaniriana 13 February 2006 (has links)
This thesis is an investigation of the natural products deriving from marine algae and cyanobacteria and has resulted in the discovery of eleven new secondary metabolites. The structure elucidations of these new molecules were performed using a variety of spectroscopic techniques. Four new macrolides were isolated and characterized from the Madagascar marine cyanobacterium Geitlerinema sp. These ankaraholides are structurally similar to the potently cytotoxic swinholides and were found to have cytotoxicities ranging from 178 nM to 354 nM against human lung cancer (NCI-H460) and mouse neuro-2a cell lines. Since swinholide-type compounds were previously localized to the heterotrophic bacteria of sponges, these findings raise intriguing questions about their true metabolic source. Geitlerinema sp. was found to be particularly rich in chemistry, and also produced the new linear lipopeptide mitsoamide with unusual structural features including an aminal moiety, a homolysine residue and a polyketide unit (3,7- dimethoxy-5-methyl- nonanedioic acid) (DMNA). A collection of the red marine alga Portieria hornemannii from the south of Madagascar (Tolagniaro, Fort Dauphin), led to the isolation of the previously reported halogenated monoterpene, halomon, and the discovery of three new related metabolites. These molecules were found to inhibit DNA methyltransferase 1 (DNMT-1). As a result of efforts to identify bioactive agents from the marine cyanobacterium Lyngbya majuscula, tanikolide dimer, a novel SIRT2 inhibitor (IC50 = 176 nM), and tanikolide seco-acid were isolated. The depside molecular structure of tanikolide dimer, which is likely a meso compound, was established by NMR, MS and chiral HPLC analyses. The structure of tanikolide dimer raises a number of intriguing configurational and biosynthetic questions for further study. The bioassay guided fractionation of a collection of the brown marine alga Dictyota sp. from Netherland Antilles Playa Fort, led to the identification of a novel HDAC inhibitor with a dolastane carbon skeleton. The novel molecule was also found to possess antimalarial activity. Other known HDAC inhibitors with interesting antimalarial activity have been reported previously, and based on this efficacy against malaria, HDAC appears to be a viable target for the development of antiparasitic agents. / Graduation date: 2006
55

The Vigani Cabinet - Analysis of historical resinous materials by gas chromatography - mass spectrometry and infrared spectroscopy / Das Vigani Kabinett - Analyse von historischen Harzen mittels Gaschromatography-Massenspectrometrie und Infrarotspectroskopie

Steigenberger, Gundel 09 July 2013 (has links) (PDF)
Natural resins have been in use for a long time and for manifold purposes resulting in a long and complex terminological history. The investigation of this history has so far been based on the connection between nomenclature and chemical composition. Because resin chemistry and the botanical classification of source plants are connected as well, the investigation of natural resins can be enhanced by adding taxonomy as an additional dimension, providing a more complex and complete picture of resin chemistry and resin use. The Vigani Cabinet, a collection of 300-year-old pharmaceutical and chemical materials owned by Queens’ College, Cambridge (UK), allows doing just that. A wide range of historical literature provides information about contemporary terminology, botanical and geographical origin, manufacture, trade and properties of resinous materials from the 18th century. This contemporary context is a particular feature of the Cabinet, which allows adding a historical dimension to the correlations between terminology, chemical composition and taxonomy. The dissertation thesis presented here provides an investigation of 17 botanical, 80 reference materials and samples from 24 natural resins from the Vigani Cabinet, studying these complex correlations and changes over time. The analytical method employed in this study was gas chromatography-mass spectrometry (GC-MS) with and without methylation with trimethylsulfoniumhydroxide. This technique provided detailed molecular compositions of the studied materials. Analysed botanical samples are taken from Pinaceae, Cupressaceae and Pistacia resins, commerical references from Araucariaceae, Copaifera, Fabaceae, Myroxylon and Burseraceae. Additionally, the soluble fraction of Baltic amber was analysed. Materials from the Vigani Cabinet analysed in this work were labelled as "turpentines", "pix burgundica", "sandaracha", "copaiba", "balsamum peruvianum and tolutanum", "mastiche", "anime", "copal", "elemi", "tacamahaca" and "succinum". Historical nomenclature of natural resins has not always been unequivocally associated with a botanical origin. The availability of natural resins changed throughout the centuries. Lack of knowledge, in particular about resins from over-seas, or adulterations resulting from changing harvesting methods, led to changes in trade names or variations in the composition of products traded under the same name. Generic names were used for resins with similar properties but different botanical (and geographical) origin. The thesis shows that a chemotaxonomic reference system is suitable for the identification of unknown resinous materials, and a number of new insights into the nomenclature of natural resins from the 17th and 18th century is obtained. The study of historical literature contributed in a significant way to the historico-cultural and archeometric research of the samples from the Vigani Cabinet and of natural resins in general and provided a basis for the interpretation of the chemical data from the Vigani samples. / Naturharze werden schon lange für sehr unterschiedliche Zwecke verwendet. Dies hat zu einer oft komplizierten Terminologie geführt, deren Untersuchung sich bisher auf den Zusammenhang zwischen dem Namen des Harzes und seiner chemischer Zusammensetzung stützte. Letztere ist aber auch mit der botanischer Herkunft und damit der Biochemie der Stammpflanze verknüpft, weshalb man chemotaxonomische Aspekte für die systematische Untersuchung von Naturharzen als zusätzliche Variablen nutzen kann. Dadurch erhält man, wie die gezeigt werden soll, ein vollständigeres und komplexeres Bild der Chemie und Nutzung von Naturharzen. Die hier präsentierte Untersuchung beschäftigt sich mit dem Vigani-Kabinett, einer 300 Jahre alten pharmazeutischen Materialiensammlung, die sich im Queens‘ College, Cambridge (UK), befindet. In der Literatur des ausgehenden 17. und des 18. Jahrhunderts finden sich zahlreiche Informationen zu Terminologie, botanischer und geographischer Herkunft, Verarbeitung, Handel und Eigenschaften von Naturharzen. Dadurch wird die historische Dimension des oben beschriebenen Zusammenhangs zwischen Terminologie, chemischer Zusammensetzung und Taxonomie erfahrbar. In der Arbeit werden 17 botanische Proben, 80 moderne Referenzmaterialien und 24 Proben aus dem Vigani-Kabinett im Hinblick auf diese Zusammenhänge und Veränderungen untersucht.Die chemischen Analysen wurden mit gekoppelter Gaschromatografie-Massenspektrometrie mit und ohne Methylierung mit Trimethylsulfoniumhydroxid durchgeführt. Damit konnte die molekulare Zusammensetzung der Proben detailliert untersucht werden. Die untersuchten botanischen Proben stammten von Pinaceae, Cupressaceae und Pistaciaharzen, kommerzielle Referenzen von Araucariaceae, Copaifera, Fabaceae, Myroxylon und Burseraceaeharzen. Zusätzlich wurde noch die lösliche Fraktion von Baltischem Bernstein untersucht. Die untersuchten Proben aus dem Vigani-Kabinett waren sowohl englisch als auch Latein mit "turpentines", "pix burgundica", "sandaracha", "copaiba", "mastiche", "anime", "copal", "elemi", "tacamahaca", "balsamum peruvianum and tolutanum" und "succinum" beschriftet. Zusammenfassend lässt sich sagen, dass die historische Nomenklatur von Naturharzen nicht immer eindeutig mit ihrem botanischen Ursprung verknüpft war. Zusätzlich veränderte sich die Erhältlichkeit der Harze im Laufe der Jahrhunderte. Durch fehlendes Wissen, insbesondere für Materialien und Pflanzen aus Übersee, oder Verfälschungen aufgrund von veränderten Fördermethoden veränderten sich die Handelsnamen dieser Materialien oder die Zusammensetzung von Materialien, die unter demselben Namen gehandelt wurden. Harze mit ähnlichen Eigenschaften aber unterschiedlichen botanischen (und geographischen) Ursprungs trugen generische Namen. Die Arbeit zeigt jedoch, dass ein chemotaxonomisches Bezugssystem die Identifizierung von unbekannten Harzen ermöglicht, und zeigt eine Reihe neuer Erkenntnisse über die Nomenklatur von Naturharzen des 17. und 18. Jahrhunderts. Die Untersuchung historischer Quellen trug dabei sehr zur Erhellung des historisch-kulturellen und archeometrischen Hintergrundes und zur Interpretation der chemischen Daten der Vigani-Proben bei.
56

Studien zur Synthese von Jatrophan-Diterpenen / Enantioselektive Synthese von (-)-15-Acetyl-3-propionyl-17-norcharaciol / Towards the synthesis of Jatrophane-diterpenes / Synthesis of the Norjatrophane Diterpene (-)-15-Acetyl-3-propionyl-17-norcharaciol

Helmboldt, Hannes 02 May 2006 (has links) (PDF)
Es wird die enantioselektive Synthese eines substituierten Cyclopentanfragmentes beschrieben, welches zur Synthese einer Vielzahl von Diterpenen aus Euphorbiaceae genutzt werden kann. Schlüsselschritt hierbei ist eine intramolekulare Carbonyl-En-Reaktion. In zwei verschiedenen Syntheseansätzen wurde versucht, dieses zu einem Jatrophan-Diterpen umzusetzen. Versuche hinsichtlich einer Nozaki-Hiyama-Kishi-Kupplung werden beschrieben. Im zweiten Ansatz, wurde über eine Ringschlussmetathese bzw. eine Relay-Ringschlussmetathese versucht entsprechende Jatrophane herzustellen. Dies gelang bei einem Substrat, welches eine zweifach substituierte Doppelbindung beinhaltet. Somit konnte ein nichtnatürliches 17-Norjatrophan enantioselektiv synthetisiert werden. / The enantioselective synthesis of a highly substituted cyclopentan, useful for the synthesis of diterpenes from Euphorbiaceae is described. Key step is a intramolecular carbonyl-en reaction. Two different approaches towards Jatrophanes were examined. The first one envisioning a Nozaki-Hiyama-Kishi coupling didn´t work. The second one employed a ring-closing-metathesis which was successful in the case of a disubstituted double bond formed. The use of an relay-ring-closing-metathesis was also examined. The enantioselective synthesis of a nonnatural 17-Norjatrophane is described in all details.
57

Studien zur Synthese von Jatrophan-Diterpenen: Enantioselektive Synthese von (-)-15-Acetyl-3-propionyl-17-norcharaciol

Helmboldt, Hannes 30 May 2006 (has links)
Es wird die enantioselektive Synthese eines substituierten Cyclopentanfragmentes beschrieben, welches zur Synthese einer Vielzahl von Diterpenen aus Euphorbiaceae genutzt werden kann. Schlüsselschritt hierbei ist eine intramolekulare Carbonyl-En-Reaktion. In zwei verschiedenen Syntheseansätzen wurde versucht, dieses zu einem Jatrophan-Diterpen umzusetzen. Versuche hinsichtlich einer Nozaki-Hiyama-Kishi-Kupplung werden beschrieben. Im zweiten Ansatz, wurde über eine Ringschlussmetathese bzw. eine Relay-Ringschlussmetathese versucht entsprechende Jatrophane herzustellen. Dies gelang bei einem Substrat, welches eine zweifach substituierte Doppelbindung beinhaltet. Somit konnte ein nichtnatürliches 17-Norjatrophan enantioselektiv synthetisiert werden. / The enantioselective synthesis of a highly substituted cyclopentan, useful for the synthesis of diterpenes from Euphorbiaceae is described. Key step is a intramolecular carbonyl-en reaction. Two different approaches towards Jatrophanes were examined. The first one envisioning a Nozaki-Hiyama-Kishi coupling didn´t work. The second one employed a ring-closing-metathesis which was successful in the case of a disubstituted double bond formed. The use of an relay-ring-closing-metathesis was also examined. The enantioselective synthesis of a nonnatural 17-Norjatrophane is described in all details.
58

The Vigani Cabinet - Analysis of historical resinous materials by gas chromatography - mass spectrometry and infrared spectroscopy

Steigenberger, Gundel 14 May 2013 (has links)
Natural resins have been in use for a long time and for manifold purposes resulting in a long and complex terminological history. The investigation of this history has so far been based on the connection between nomenclature and chemical composition. Because resin chemistry and the botanical classification of source plants are connected as well, the investigation of natural resins can be enhanced by adding taxonomy as an additional dimension, providing a more complex and complete picture of resin chemistry and resin use. The Vigani Cabinet, a collection of 300-year-old pharmaceutical and chemical materials owned by Queens’ College, Cambridge (UK), allows doing just that. A wide range of historical literature provides information about contemporary terminology, botanical and geographical origin, manufacture, trade and properties of resinous materials from the 18th century. This contemporary context is a particular feature of the Cabinet, which allows adding a historical dimension to the correlations between terminology, chemical composition and taxonomy. The dissertation thesis presented here provides an investigation of 17 botanical, 80 reference materials and samples from 24 natural resins from the Vigani Cabinet, studying these complex correlations and changes over time. The analytical method employed in this study was gas chromatography-mass spectrometry (GC-MS) with and without methylation with trimethylsulfoniumhydroxide. This technique provided detailed molecular compositions of the studied materials. Analysed botanical samples are taken from Pinaceae, Cupressaceae and Pistacia resins, commerical references from Araucariaceae, Copaifera, Fabaceae, Myroxylon and Burseraceae. Additionally, the soluble fraction of Baltic amber was analysed. Materials from the Vigani Cabinet analysed in this work were labelled as "turpentines", "pix burgundica", "sandaracha", "copaiba", "balsamum peruvianum and tolutanum", "mastiche", "anime", "copal", "elemi", "tacamahaca" and "succinum". Historical nomenclature of natural resins has not always been unequivocally associated with a botanical origin. The availability of natural resins changed throughout the centuries. Lack of knowledge, in particular about resins from over-seas, or adulterations resulting from changing harvesting methods, led to changes in trade names or variations in the composition of products traded under the same name. Generic names were used for resins with similar properties but different botanical (and geographical) origin. The thesis shows that a chemotaxonomic reference system is suitable for the identification of unknown resinous materials, and a number of new insights into the nomenclature of natural resins from the 17th and 18th century is obtained. The study of historical literature contributed in a significant way to the historico-cultural and archeometric research of the samples from the Vigani Cabinet and of natural resins in general and provided a basis for the interpretation of the chemical data from the Vigani samples.:CONTENTS 1 INTRODUCTION 1 1.1 Natural resins in a historical and modern context 1 1.2 The Vigani Cabinet and its historical background 3 1.3 Aim of the thesis - outline 6 2 LITERATURE REVIEW 8 2.1 Gymnosperm resins – conifer resins and products 9 2.1.1 Pinaceae 9 2.1.2 Cupressaceae 17 2.1.3 Araucariaceae 20 2.2 Angiosperm resins I – Fabales 21 2.3 Angiosperm resins II – Sapindales 30 2.3.1 Anacardiaceae 30 2.3.2 Burseraceae 35 2.3.3 Rutaceae 43 2.4 Fossil resins 45 2.5 Summary and research deficits 49 3 EXPERIMENTAL 53 3.1 Coupled gas chromatography and mass spectrometry 53 3.1.1 Materials 53 3.1.2 Sample preparation 54 3.1.3 Instrumentation 54 3.1.4 Data-Evaluation 58 3.2 Fourier transformation infrared spectroscopy 60 3.2.1 Sample preparation 61 3.2.2 Instrumentation 61 3.2.3 Data evaluation 61 4 RESULTS – REFERENCE MATERIALS 62 4.1 Gymnosperm resins – conifer resins and products 62 4.1.1 Pinaceae – Coniferous turpentines 62 4.1.1.1 Phytochemical markers – detection of adulterations 62 4.1.1.2 Aging by heat and light 73 4.1.2 Cupressaceae – Sandarac 80 4.1.3 Araucariaceae – Coniferous copals 88 4.1.4 Discussion 91 4.2 Angiosperm Resins I - Fabales 94 4.2.1 Copaifera – Copaiba balsam 94 4.2.2 Legume copals 102 4.2.3 Myroxylon – Balsam of Tolu and Peru 108 4.2.4 Discussion 117 4.3 Angiosperm resins II - Sapindales 120 4.3.1 Anacardiaceae – Pistacia resins 120 4.3.2 Burseraceae – Elemi, copal and others 127 4.3.3 Discussion 142 4.4 Fossil resins 144 4.4.1 Baltic amber 144 4.4.2 Discussion 153 4.5 Summary and research deficits 155 5 RESULTS – RESINOUS MATERIALS FROM THE VIGANI CABINET 160 5.1 Gymnosperm resins – conifer resins and products 162 5.1.1 1/8 Terebin. Strasb. 163 5.1.2 1/9 Tereb Com 170 5.1.3 1/10 Venice Turpentine 176 5.1.4 1/11 Venic. Turpent. 183 5.1.5 1/13 Tereb E Chio 188 5.1.6 A/23 Pix Burgundica 194 5.1.7 A/26 Sandaracha 203 5.2 Angiosperm resins I - Fabales 210 5.2.1 1/4 Balsam Cipivi 211 5.2.2 A/5 Gum Animi 218 5.2.3 La2/7 Unknown resin 228 5.2.4 1/31 Bals Peruv 230 5.2.5 2/1 Bals Peru 237 5.2.6 Z/17 Balsam Tolutanum 240 5. 3 Angiosperm resins II – Sapindales 245 5.3.1 A/11 Mastiche 246 5.3.2 1/14 Tereb i E Cypri 252 5.3.3 A/21 Gum Copal 258 5.3.4 A/24 [.] Elemi 268 5.3.5 A/22 Tacamahaca 276 5.3.6 Z/1 Tacamahaca 283 5.4 Fossil Resins 287 5.4.1 E/13 Succinum Citrinum 288 5.4.2 E/14 Succinum flavan 295 5.4.3 E/15 Succinum albam 302 5.4.4 E/16 Succinum nigram 307 5.4.5 F/13 L. Gagatis 313 6 CONCLUSIONS 316 7 REFERENCES 324 APPENDIX 365 Investigated materials from the Vigani Cabinet 366 Annotated list of historical literature 367 List of figures 374 List of tables 379 Compound lists 381 Atlas of mass spectra 422 / Naturharze werden schon lange für sehr unterschiedliche Zwecke verwendet. Dies hat zu einer oft komplizierten Terminologie geführt, deren Untersuchung sich bisher auf den Zusammenhang zwischen dem Namen des Harzes und seiner chemischer Zusammensetzung stützte. Letztere ist aber auch mit der botanischer Herkunft und damit der Biochemie der Stammpflanze verknüpft, weshalb man chemotaxonomische Aspekte für die systematische Untersuchung von Naturharzen als zusätzliche Variablen nutzen kann. Dadurch erhält man, wie die gezeigt werden soll, ein vollständigeres und komplexeres Bild der Chemie und Nutzung von Naturharzen. Die hier präsentierte Untersuchung beschäftigt sich mit dem Vigani-Kabinett, einer 300 Jahre alten pharmazeutischen Materialiensammlung, die sich im Queens‘ College, Cambridge (UK), befindet. In der Literatur des ausgehenden 17. und des 18. Jahrhunderts finden sich zahlreiche Informationen zu Terminologie, botanischer und geographischer Herkunft, Verarbeitung, Handel und Eigenschaften von Naturharzen. Dadurch wird die historische Dimension des oben beschriebenen Zusammenhangs zwischen Terminologie, chemischer Zusammensetzung und Taxonomie erfahrbar. In der Arbeit werden 17 botanische Proben, 80 moderne Referenzmaterialien und 24 Proben aus dem Vigani-Kabinett im Hinblick auf diese Zusammenhänge und Veränderungen untersucht.Die chemischen Analysen wurden mit gekoppelter Gaschromatografie-Massenspektrometrie mit und ohne Methylierung mit Trimethylsulfoniumhydroxid durchgeführt. Damit konnte die molekulare Zusammensetzung der Proben detailliert untersucht werden. Die untersuchten botanischen Proben stammten von Pinaceae, Cupressaceae und Pistaciaharzen, kommerzielle Referenzen von Araucariaceae, Copaifera, Fabaceae, Myroxylon und Burseraceaeharzen. Zusätzlich wurde noch die lösliche Fraktion von Baltischem Bernstein untersucht. Die untersuchten Proben aus dem Vigani-Kabinett waren sowohl englisch als auch Latein mit "turpentines", "pix burgundica", "sandaracha", "copaiba", "mastiche", "anime", "copal", "elemi", "tacamahaca", "balsamum peruvianum and tolutanum" und "succinum" beschriftet. Zusammenfassend lässt sich sagen, dass die historische Nomenklatur von Naturharzen nicht immer eindeutig mit ihrem botanischen Ursprung verknüpft war. Zusätzlich veränderte sich die Erhältlichkeit der Harze im Laufe der Jahrhunderte. Durch fehlendes Wissen, insbesondere für Materialien und Pflanzen aus Übersee, oder Verfälschungen aufgrund von veränderten Fördermethoden veränderten sich die Handelsnamen dieser Materialien oder die Zusammensetzung von Materialien, die unter demselben Namen gehandelt wurden. Harze mit ähnlichen Eigenschaften aber unterschiedlichen botanischen (und geographischen) Ursprungs trugen generische Namen. Die Arbeit zeigt jedoch, dass ein chemotaxonomisches Bezugssystem die Identifizierung von unbekannten Harzen ermöglicht, und zeigt eine Reihe neuer Erkenntnisse über die Nomenklatur von Naturharzen des 17. und 18. Jahrhunderts. Die Untersuchung historischer Quellen trug dabei sehr zur Erhellung des historisch-kulturellen und archeometrischen Hintergrundes und zur Interpretation der chemischen Daten der Vigani-Proben bei.:CONTENTS 1 INTRODUCTION 1 1.1 Natural resins in a historical and modern context 1 1.2 The Vigani Cabinet and its historical background 3 1.3 Aim of the thesis - outline 6 2 LITERATURE REVIEW 8 2.1 Gymnosperm resins – conifer resins and products 9 2.1.1 Pinaceae 9 2.1.2 Cupressaceae 17 2.1.3 Araucariaceae 20 2.2 Angiosperm resins I – Fabales 21 2.3 Angiosperm resins II – Sapindales 30 2.3.1 Anacardiaceae 30 2.3.2 Burseraceae 35 2.3.3 Rutaceae 43 2.4 Fossil resins 45 2.5 Summary and research deficits 49 3 EXPERIMENTAL 53 3.1 Coupled gas chromatography and mass spectrometry 53 3.1.1 Materials 53 3.1.2 Sample preparation 54 3.1.3 Instrumentation 54 3.1.4 Data-Evaluation 58 3.2 Fourier transformation infrared spectroscopy 60 3.2.1 Sample preparation 61 3.2.2 Instrumentation 61 3.2.3 Data evaluation 61 4 RESULTS – REFERENCE MATERIALS 62 4.1 Gymnosperm resins – conifer resins and products 62 4.1.1 Pinaceae – Coniferous turpentines 62 4.1.1.1 Phytochemical markers – detection of adulterations 62 4.1.1.2 Aging by heat and light 73 4.1.2 Cupressaceae – Sandarac 80 4.1.3 Araucariaceae – Coniferous copals 88 4.1.4 Discussion 91 4.2 Angiosperm Resins I - Fabales 94 4.2.1 Copaifera – Copaiba balsam 94 4.2.2 Legume copals 102 4.2.3 Myroxylon – Balsam of Tolu and Peru 108 4.2.4 Discussion 117 4.3 Angiosperm resins II - Sapindales 120 4.3.1 Anacardiaceae – Pistacia resins 120 4.3.2 Burseraceae – Elemi, copal and others 127 4.3.3 Discussion 142 4.4 Fossil resins 144 4.4.1 Baltic amber 144 4.4.2 Discussion 153 4.5 Summary and research deficits 155 5 RESULTS – RESINOUS MATERIALS FROM THE VIGANI CABINET 160 5.1 Gymnosperm resins – conifer resins and products 162 5.1.1 1/8 Terebin. Strasb. 163 5.1.2 1/9 Tereb Com 170 5.1.3 1/10 Venice Turpentine 176 5.1.4 1/11 Venic. Turpent. 183 5.1.5 1/13 Tereb E Chio 188 5.1.6 A/23 Pix Burgundica 194 5.1.7 A/26 Sandaracha 203 5.2 Angiosperm resins I - Fabales 210 5.2.1 1/4 Balsam Cipivi 211 5.2.2 A/5 Gum Animi 218 5.2.3 La2/7 Unknown resin 228 5.2.4 1/31 Bals Peruv 230 5.2.5 2/1 Bals Peru 237 5.2.6 Z/17 Balsam Tolutanum 240 5. 3 Angiosperm resins II – Sapindales 245 5.3.1 A/11 Mastiche 246 5.3.2 1/14 Tereb i E Cypri 252 5.3.3 A/21 Gum Copal 258 5.3.4 A/24 [.] Elemi 268 5.3.5 A/22 Tacamahaca 276 5.3.6 Z/1 Tacamahaca 283 5.4 Fossil Resins 287 5.4.1 E/13 Succinum Citrinum 288 5.4.2 E/14 Succinum flavan 295 5.4.3 E/15 Succinum albam 302 5.4.4 E/16 Succinum nigram 307 5.4.5 F/13 L. Gagatis 313 6 CONCLUSIONS 316 7 REFERENCES 324 APPENDIX 365 Investigated materials from the Vigani Cabinet 366 Annotated list of historical literature 367 List of figures 374 List of tables 379 Compound lists 381 Atlas of mass spectra 422

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