Alkaloids of Athrotaxis species

A detailed phytochemical examination of the alkaloid content of three species of the family Taxodiaceae, Athrotaxis cupressoides D. Don, Athrotaxis selaginoides D. Don, and Athrotaxis laxifolia Hook has been undertaken. A total of twelve alkaloids were isolated; the alkaloids proved to have structures of the homoerythrina type, and included five known bases previously isolated from other plants. Spectroscopic and chemical evidence for the structures of the seven new alkaloids are presented in Chapter II. The synthesis of the homoerythrina alkaloid skeleton has been attempted by two different approaches as presented in Chapter III, and the work done on homoerythrina alkaloids has been briefly reviewed in Chapter I. Discaria toumatou and Discaria pubescens, members of the family Rhamnaceae, have been investigated. The alkaloids present were found to have the benzylisoquinoline type of structure, and the results appear in Chapter IV. A preliminary investigation of Hypserpa veillardii, a species of the family Menispermaceae, has been made, and the results appear in Chapter V. The known bisbenzylisoquinoline alkaloid limacine was the only base to be isolated.