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The Global ETD Search service is a free service for researchers
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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.
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Synthesis of azaindoles, diazaindoles, and advanced carbazole alkaloid intermediates via palladium-catalyzed reductive N-heteroannulationCarrero-Martinez, Grissell M. January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains ix, 74 p. : ill. Includes abstract. Includes bibliographical references (p. 58-60).
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Palladium(II)-catalysed total synthesis of naturally occurring pyrano[3,2-a]carbazole and pyrano[2,3-b]carbazole alkaloidsHesse, Ronny, Jäger, Anne, Schmidt, Arndt W., Knölker, Hans-Joachim 21 July 2014 (has links) (PDF)
Seven naturally occurring pyranocarbazole alkaloids (pyrayafoline A–E, O-methylmurrayamine A and O-methylmahanine) have been obtained by total synthesis using a palladium(II)-catalysed oxidative cyclisation of a diarylamine to an orthogonally diprotected 2,7-dihydroxycarbazole as key step.
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Iron-mediated Synthesis of the AntiostatinsKnott, Kerstin 20 March 2009 (has links) (PDF)
Within this thesis the first total syntheses of eight biologically active natural products from the family of carbazole alkaloids, antiostatins A1 to A4 and B2 to B5, were established. Spectroscopic data of the synthesised natural products are in good agreement with the isolated antiostatins from Streptomyces cyaneus 2007-SV1, which confirms the molecular structures assigned to the natural products. The total synthesis of the antiostatins A1 to A4 and B2 to B5 were achieved employing the iron-mediated synthesis to form the carbazole nucleus from a cyclohexadienylium iron salt and appropriate arylamines. This transition metal-mediated approach could be applied to all antiostatins in excellent yields. The antiostatins A1-4 and B2-5 represent the first carbazole alkaloids with an acetamide or substituted biuret chain. Introduction of the sophisticated substituents proceeded selectively on C-4 in high yields. Antiostatins A1 to A4 and B2 to B5 could be synthesised over eight steps from a tricarbonyliron-coordinated cyclohexadienylium salt. The overall yields are in the range of 31 – 63%.
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Palladium(II)-catalysed total synthesis of naturally occurring pyrano[3,2-a]carbazole and pyrano[2,3-b]carbazole alkaloidsHesse, Ronny, Jäger, Anne, Schmidt, Arndt W., Knölker, Hans-Joachim 21 July 2014 (has links)
Seven naturally occurring pyranocarbazole alkaloids (pyrayafoline A–E, O-methylmurrayamine A and O-methylmahanine) have been obtained by total synthesis using a palladium(II)-catalysed oxidative cyclisation of a diarylamine to an orthogonally diprotected 2,7-dihydroxycarbazole as key step.
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Total synthesis of the cyclic monoterpenoid pyrano[3,2-a]carbazole alkaloids derived from 2-hydroxy-6-methylcarbazoleGassner, Cemena, Hesse, Ronny, Schmidt, Arndt W., Knölker, Hans-Joachim January 2014 (has links)
The synthesis of seven pyrano[3,2-a]carbazole alkaloids has been achieved using their putative biogenetic precursor 2-hydroxy-6-methylcarbazole as key intermediate.
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Total synthesis of the cyclic monoterpenoid pyrano[3,2-a]carbazole alkaloids derived from 2-hydroxy-6-methylcarbazoleGassner, Cemena, Hesse, Ronny, Schmidt, Arndt W., Knölker, Hans-Joachim 09 February 2015 (has links) (PDF)
The synthesis of seven pyrano[3,2-a]carbazole alkaloids has been achieved using their putative biogenetic precursor 2-hydroxy-6-methylcarbazole as key intermediate.
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Iron-mediated Synthesis of the AntiostatinsKnott, Kerstin 16 February 2009 (has links)
Within this thesis the first total syntheses of eight biologically active natural products from the family of carbazole alkaloids, antiostatins A1 to A4 and B2 to B5, were established. Spectroscopic data of the synthesised natural products are in good agreement with the isolated antiostatins from Streptomyces cyaneus 2007-SV1, which confirms the molecular structures assigned to the natural products. The total synthesis of the antiostatins A1 to A4 and B2 to B5 were achieved employing the iron-mediated synthesis to form the carbazole nucleus from a cyclohexadienylium iron salt and appropriate arylamines. This transition metal-mediated approach could be applied to all antiostatins in excellent yields. The antiostatins A1-4 and B2-5 represent the first carbazole alkaloids with an acetamide or substituted biuret chain. Introduction of the sophisticated substituents proceeded selectively on C-4 in high yields. Antiostatins A1 to A4 and B2 to B5 could be synthesised over eight steps from a tricarbonyliron-coordinated cyclohexadienylium salt. The overall yields are in the range of 31 – 63%.
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Efficient iron-mediated approach to pyrano[3,2-a]carbazole alkaloids - first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine, first asymmetric synthesis and assignment of the absolute configuration of (−)-trans-dihydroxygirinimbineGruner, Konstanze K., Hopfmann, Thomas, Matsumoto, Kazuhiro, Jäger, Anne, Katsuki, Tsutomu, Knölker, Hans-Joachim 02 April 2014 (has links) (PDF)
Iron-mediated oxidative cyclisation provides an efficient approach to pyrano[3,2-a]carbazole alkaloids. Thus, improved routes to girinimbine and murrayacine as well as the first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine are reported. Asymmetric epoxidation of girinimbine led to (−)-trans-dihydroxygirinimbine and the assignment of its absolute configuration. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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Regioselective prenylation of bromocarbazoles by palladium(0)-catalysed cross coupling – synthesis of O-methylsiamenol, O-methylmicromeline and carquinostatin AThomas, Claudia, Kataeva, Olga, Schmidt, Arndt W., Knölker, Hans-Joachim 02 December 2019 (has links)
We describe the regioselective prenylation of 3-bromocarbazole by palladium(0)-catalysed cross coupling with a prenylstannane or a prenylboronate. The procedure is applied to the synthesis of precursors for biologically active carbazole alkaloids.
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Efficient iron-mediated approach to pyrano[3,2-a]carbazole alkaloids - first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine, first asymmetric synthesis and assignment of the absolute configuration of (−)-trans-dihydroxygirinimbineGruner, Konstanze K., Hopfmann, Thomas, Matsumoto, Kazuhiro, Jäger, Anne, Katsuki, Tsutomu, Knölker, Hans-Joachim January 2011 (has links)
Iron-mediated oxidative cyclisation provides an efficient approach to pyrano[3,2-a]carbazole alkaloids. Thus, improved routes to girinimbine and murrayacine as well as the first total syntheses of O-methylmurrayamine A and 7-methoxymurrayacine are reported. Asymmetric epoxidation of girinimbine led to (−)-trans-dihydroxygirinimbine and the assignment of its absolute configuration. / Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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