Synthetic approaches to polyoxygenated chromone and chromanome natural products

Wootton, RCR

Abstract

The work described in this thesis is concerned with the chemistry of
polymethoxylated aromatic carbonyl compounds bearing a 2,6-dioxygenated
substitution pattern, with particular regard to establishing synthetic routes to
biologically active chromone and chromanone systems. Syntheses of key
intermediates in the approaches to the natural products stigmatellin, baicalein and
LL-D253(x (and related products) were undertaken.
In chapter one the reactions of nucleophiles at the carbonyl moieties of 2,6-
dioxygenated benzene carbonyl compounds are reviewed. This type of process
o
can present special difficulties and was to prove particularly significant at various
stageso f the work describedi n subsequenct hapters.
Chapter two is a review of the provenance, abundance, biosynthesis, and previous
syntheses of the natural products stigmatellin, baicalein and LL-D253(x, these
being the targets of the synthetic work undertaken in the course of the project.
Chapter three is concerned with an approach to a fragment of the stigmatellin
molecule (referred to as stigmatellin fragment A) using the Vilsmeier formylation
reaction, while chapter four is concerned with an alternative approach to
stigmatellin fragment A using Friedel-Crafts acylation methodology. The
strategies and the results obtained are described and analysed in detail.
In chapter five a strategy for the synthesis of baicalein trimethyl ether is described
and the results obtained are discussed.

Citation

Wootton, R. Synthetic approaches to polyoxygenated chromone and chromanome natural products. (Thesis). University of Salford, UK

• Thesis Type: Thesis
• Deposit Date: Jul 1, 2009
• Publicly Available Date: Jul 1, 2009
• Additional Information: Additional Information : PhD supervisor: Dr. Tim Wallace
• Award Date: Apr 1, 2000