Stereochemical Studies in the Steroid Series
Tez Türü: Doktora
Tezin Yürütüldüğü Kurum: University of Sussex, Kimya Fakültesi, Organik Kimya, Birleşik Krallık
Tez Danışmanı: Prof. James R. Hanson
Tezin Onay Tarihi: 1998
Tezin Dili: İngilizce
Desteklendiği Program: Diğer
Özet:
The introduction of the thesis provides a brief review of the
literature on the conformational analysis of steroids and their reactions.
The preparation
of A-nor and B-norsteroids form the subject of chapter 2. A new simple
synthetic route to prepare these steroids has been devised involving
cyclization using the modified McMurry reagent.
Chapter 3
describes the chemistry of the hydroboration, epoxidation and osmylation of
these norsteroids. The preparation of some norsteroid anologues of aromatase
inhibitors is also described.
Chapter 4 describes the synthesis of 13a-methyl and 13b-methyl steroids in which the functional groups associated with the biological activity of the tumour inhibitor, aphidicolin, have been introduced onto steroid backbone in order to attempt to combine the biological activity of the two classes of compounds. In this chapter attempts to construct a furan ring between rings A and B of cholesterol are also described.
The stereochemistry of oxidation of steroidal alkenes with sodium perborate : potassium permanganate in different solvents is examined in chapter 5. This is the first application in the literature of this reagent for such a purpose. The regio- and stereochemistry of the alcoholysis of the pairs of epimeric steroid epoxides catalysed by tetracyanoethylene was examined. The effect of a neighbouring hydroxy group on the regiochemistry of the methanolysis of an epoxide catalysed by TCNE was reported.
In chapter 6 investigation on stereochemistry of the
formation of elimination products in the hydroboration of a 5b-hydroxyandrost-3-ene using
deuterium labelling are reported.
The compounds were identified by spectroscopic methods and partly by X-ray crystallography. The 13C NMR spectra assignments of some of the compounds prepared during these studies are given in the appendix.