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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.
111

Structure Elucidation and Synthesis of Natural Products

Murphy, Annabel Christine January 2008 (has links)
In this thesis, synthetic chemistry was used as a tool in the exploration of various aspects of natural products discovered by the natural products research group at the University of Canterbury. Work on the constituent amino acids and connectivity of the pteratides, a potently cytotoxic series of cyclodepsipeptides, had been completed before the beginning of this work (carried out by Miss C. Chen). The elucidation of the stereochemistry of the constituent amino acids was undertaken in this present work. The synthesis of all stereochemical entities of a number of unusual amino acids, which were either not available commercially or were expensive, was carried out, providing reference materials for comparison to the natural products. The synthesis of the diastereoisomers of one of these amino acids, 4-methylproline, was carried out by modification of literature procedures, which led to the development of an improved, concise and stereoselective synthesis. The hydrolysis of the natural products, derivatisation of the resultant hydrolysates, synthetic and commercial reference amino acids and HPLC analysis allowed the full stereochemical assignment of the pteratide series. The total synthesis of spiro-mamakone A, a cytotoxic polyketide isolated by Dr S. van der Sar, was undertaken. The synthesis was not successfully completed due to difficulties in the late-stage formation of a crucial enedione motif. However, very advanced intermediates were successfully synthesised. These synthetic analogues of the natural product were analysed for biological activity, allowing valuable insight into the structure-activity relationship, for example, demonstrating the importance of the enedione moiety to biological activity.
112

Application of selective methods in the search for new bioactive natural products from fungi

Chamyuang, Sunita January 2010 (has links)
The work undertaken explored the potential for discovery of new bioactive metabolites from soil fungi. The research developed selective mycological isolation techniques and maximised metabolite production from active selected fungi by application of the OSMAC approach and concept of hormesis. Novel active compounds were discovered and many other known compounds characterised.
113

Carbenoid insertion chemistry on furanose platforms as a route to natural product frameworks /

Patton, Jennie L. January 2008 (has links)
Thesis (M.S.)--Youngstown State University, 2008. / Includes bibliographical references (leaves 47-50). Also available via the World Wide Web in PDF format.
114

Studies of natural products that reveal novel strategies for efficient modification of DNA

Szekely, Joseph, January 2006 (has links)
Thesis (Ph.D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on April 24, 2009) Vita. Includes bibliographical references.
115

Application of a particle filtration method in the search for new bioactive natural products from fungi : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Microbiology in the University of Canterbury /

Yusof, Mohd. Termizi bin. January 1900 (has links)
Thesis (M. Sc.)--University of Canterbury, 2008. / Typescript (photocopy). "March 2008." Includes bibliographical references (leaves 88-94). Also available via the World Wide Web.
116

Biosynthetic studies of secondary metabolites by mass spectrometry

Ntai, Ioanna. January 2008 (has links)
Thesis (Ph. D. in Chemistry)--Vanderbilt University, Aug. 2008. / Title from title screen. Includes bibliographical references.
117

The distribution, biosynthetic origin and functional significance of Tyrian purpe precursors in the Australian muricid Dicathais orbita (Neogastropoda : Muricidae)

Westley, Chantel Barbara, January 2008 (has links)
Thesis (Ph.D.)--Flinders University, School of Biological Sciences. / Typescript bound. Includes bibliographical references: (p. 237-268) Also avaialable online.
118

Vinyloxocarbenium ions and cyclopentenyl oxyallyl, zwitterions in 4+3 cyloadddition reactions /

Rashatasakhon, Paitoon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 250-261). Also available on the Internet.
119

Vinyloxocarbenium ions and cyclopentenyl oxyallyl, zwitterions in 4+3 cyloadddition reactions

Rashatasakhon, Paitoon, January 2002 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 250-261). Also available on the Internet.
120

Marine natural products as antimicrobial chemical defenses and sources of potential drugs

Lane, Amy L. January 2008 (has links)
Thesis (Ph. D.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009. / Committee Chair: Kubanek, Julia; Committee Member: Fernandez, Facundo M.; Committee Member: Harvey, Stephen C.; Committee Member: Hay, Mark E.; Committee Member: Hud, Nicholas V. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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