Thesis (Ph. D.)--University of Wisconsin--Madison, 1959. / Typescript with manuscript equations. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Hong Kong, 2000. / Includes bibliographical references (leaves 175-187).

Thesis (M.Sc.(Chemistry))--University of Pretoria, 2001. / Includes abstracts in English and Afrikaans. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1965. / Typescript. Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1976. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1973. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographies.

The chapter of stereochemistry which deals with the attempted resolution of saturated tervalent nitrogen compounds is a long and interesting one, but is as yet incomplete. The problem has been attacked in many ways; but despite the great amount of work which has been carried out the failure to achieve the resolution of such compounds has been complete.

An examination of an organic extract of the cyanobacterium Lyngbya majuscula collected from Wasini Island off the southern Kenyan coast led to the isolation of the known cyclodepsipeptide antanapeptin A (7), recently isolated from a Madagascan collection of L. majuscula, and a new bioactive cyclodepsipeptide, homodolastatin 16 (42). Although L. majuscula is a common, pantropical cyanobacterium this study represents the first investigation of the natural product chemistry of a Kenyan population of L. majuscula. The structures of the two cyclodepsipeptides were determined from 2D NMR and mass spectrometry data. The L- stereochemistry of the proline, valine, and N-methylphenylalanine amino acids in 7 and the L – proline configuration in 42, was confirmed by Marfey’s HPLC method. Chiral GC was used to determine the absolute stereochemistry of the hydroxyisovaleric acid moiety in 7 and 42, the lactate residue in 42 and tentatively propose an L-stereochemistry for the Nmethylisoleucine amino acid in 42. Homodolastatin 16, a higher homologue of the potential anti-cancer agent, dolastatin 16, exhibited moderate activity against two oesophageal cancer cell lines.

No description available.

No description available.