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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

Synthetic studies of nonadrides

Drapela, Nicholas Ernest 14 August 1998 (has links)
An asymmetric approach to the synthesis of byssochlamic acid (1) is described. Regioisomeric enzymatic differentiation is described in the selective hydrolysis of dimethyl ester 30 by porcine liver esterase. Chiral dimethyl ester 42 was prepared by desymmetrization of cyclopentene 34 using porcine liver esterase. A key intramolecular [2+2]cycloaddition-cycloreversion photometathesis of diolide 69 was unsuccessful. An advanced intermediate 77 along an alternate route to 1 was synthesized. A synthetic route to bromoenone 164 has been completed. Compound 164 was utilized in a model study for a vinyl radical cyclization approach to the bicyclic core of CP-225,917 (8) and CP-263,114 (9). The strategy employs Birch reduction of o-anisaldehyde derivative 152 and elaboration of the side chain to provide an efficient route to 164. Initial attempts at cyclization to bicyclo[4.3.1]dec-1-ene 165 using tributyltin hydride and 2,2'-azobisisobutyronitrile (AIBN) were carried out, but no desired product was isolated under these conditions. / Graduation date: 1999
2

Quantitation of cyanide detoxification product ß-cyanoalanine by LC-MS/MS in plant tissue and mitochondrial preparation

Wu, Jianfeng, 吳劍鋒 January 2014 (has links)
abstract / Biological Sciences / Master / Master of Philosophy
3

Elucidation of the biosynthetic pathway of a tripyrrole secondary metabolite, prodigiosin

Bhalara, Hiral Dolarbhai January 2011 (has links)
No description available.
4

Studies towards the total synthesis of (-)-kendomycin /

Smits, Helmars. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2007. / Printout. Includes bibliographical references (leaves 126-130). Also available on the World Wide Web.
5

The biosynthesis of the sterpurenes

Leech, Andrew Peter January 1990 (has links)
No description available.
6

Characterization of bioactive secondary metabolites from Pseudomonas aeruginosa and Prorocentrum species /

Williams, Jennifer S. January 2003 (has links) (PDF)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaves : 85-91).
7

Microbial metabolites : structure and function of bacterial siderophores from Pseudomonas species and identification of secondary metabolites excreted by brown rot fungi Gleophyllum species /

Zawadzka, Anna M. January 1900 (has links)
Thesis (Ph. D.)--University of Idaho, 2005. / Also available online in PDF format. Abstract. "December 2005." Includes bibliographical references.
8

Chemical characterisation of microbial natural products from underexplored habitats

Elsayed, Somayah Sameer January 2015 (has links)
No description available.
9

Papaver somniferum and P. bracteatum : tissue culture and morphinan alkaloid production

Day, Keith B. January 1987 (has links)
Papaver somniferum plants accumulate the secondary products codeine and morphine. P. bracteatum accumulates their precursor, thebaine. The aims of the project were to use tissue cultures for the production of these alkaloids and for the biotransformation of thebaine to codeine and morphine. Methods were evaluated for the extraction, separation and quantification of mg or mug amounts of morphinan alkaloids from plant material. TLC, IIPLC and RIA were useful. Poppy cells fron a range of seed sources and explants were grown in static and suspension culture. Manipulations were made in atterpts to induce morphinan biogenesis. These included inmobilisation of cells and changes in the growth medium. Morphinans were absent from unspecialised cells in all but one instance. The biotransformation of thebaine was tested in cell suspensions of P. somniferum and Nicotiana alata. Using thebaine (biosynthesised from CO2) these experiments were extended to organs of the P. somniferum plant. A thebaine-biotransfomation product arose in N. alata (but not P. somniferum) suspensions that also arose in excised P. somniferum capsules. A non-specific enzymic activity is proposed. No codeine or morphine were produced. Plant regeneration was demonstrated, in good yield, by embryogenesis fron meristenoid tissue of P. bracteatum. In P. somniferum the process was initiated but was not routinely successful. Regeneration may be useful for plant improvenent via cloning or as a source of variation. On reorganisation into plantlets, capacity for morphinan alkaloid accumulation was realised. Capacity for alkaloid accumulation is discussed in tenns of a requisite minimum level of cytodifferentiation, perhaps of laticifer-like cells. The uptake or binding of radiolabelled morphine by suspension cultures was investigated, since binding may be a reason for failure to detect morphinans in cultures extracted by the usual methods. Evidence was found that exogenous morphine binds to an insoluble fraction in P. somniferum and I. tabacum but cells did not contain any endogenous bound morphincins.
10

Studies on the metabolites of the entomopathogenic fungus metarhizium anisoplae with specific reference to destruxin

Abdrahman Kohmani, Ahmed Ali January 2014 (has links)
No description available.

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