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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

The isolation and structure elucidation of veratrum alkaloids

Gruenfeld, Norbert, January 1960 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1960. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Studies on total synthesis of veratrum alkaloids

Brookes, Roderick William January 1969 (has links)
The initial work toward a synthetic entry into the hexacyclic cevane nucleus (7) is described, and the specific application of this work to the total synthesis of verticine (12) is discussed. Hecogenin acetate (74) was converted to C-nor-D-homo-(25 R)-5α-spirost-13(18)-en-3β-ol-3-acetate (79) via a known procedure, and hydroboration of the double bond gave the corresponding 13β-hydroxymethyl compound (80(a)). The mass spectral fragmentation of the spiroketal system is discussed. The stereochemistry at C-13 of the hydroborated compound (80(a)) was reversed by oxidation of the primary alcohol to the aldehyde, epimerization, and reduction. Acetylation gave the diacetate (85) which was used in investigation of the spiroketal side chain degradation. The Baeyer-Villiger oxidation sequence developed by W.F. Johns was used in the spiroketal degradation. 13α-Acetoxymethyl-17-acetyl-18-nor-5α-etiojerv-16(17)-en-3β-ol-3-acetate (110) was obtained with considerable difficulty in low yield from this sequence, A model compound, 17-acetyl-5α, 13β-etiojerv-16(17)-en-3β-ol (111), was employed to test the feasibility of attachment of a heterocyclic portion via a reaction developed by Schreiber and Adam. Reduction of the double bond and epimerization of the methyl ketone gave the ketone (120), which was then condensed with 2-lithio-5-methylpyridine. The structure of the condensation product was established by its n.m.r. and mass spectra. / Science, Faculty of / Chemistry, Department of / Graduate
3

Chromatographic studies on the sabadilla alkaloids

Hennig, Arnold John, January 1950 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1950. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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