Towards the Total Synthesis of Anthraquinone Antifungal Agents Sch 47554 and Sch 47555
Author(s)
Espensen, George Max
Type
Thesis
Abstract
The total synthesis of Sch 47554 (1) is the focus of this project, with the intention of
using two aryne-furan cycloaddition reactions to efficiently build the anthraquinone
core of the molecule. The first is intermolecular with furan, which is then elaborated
with a C-aryl glycosidation reaction. The second is intramolecular between 5 and 6
where the two fragments are linked by a disposable tether connected through the
oxygen functionalities, as demonstrated in 2. This ensures the correct angularly-fused
regiochemistry of the aryne-furan cycloaddition.
[Molecular structure diagrams appear here. To view, please open pdf attachment]. To this end suitable precursors have been examined. After several unsuccessful
attempts at making various suitably-functionalised precursors, double aryne precursor
8 was synthesised and converted into naphthol 10. This was successfully
glycosylated, but this substrate is less flexible later in the synthesis than another substrate developed, 9. This was converted into naphthol 10 and the glycosidation is
currently being optimised. Elsewhere in the group furan 6 has been synthesised. These
systems are appropriate for completing the synthesis of 1. [Molecular structure diagrams appear here. To view, please open pdf attachment].
using two aryne-furan cycloaddition reactions to efficiently build the anthraquinone
core of the molecule. The first is intermolecular with furan, which is then elaborated
with a C-aryl glycosidation reaction. The second is intramolecular between 5 and 6
where the two fragments are linked by a disposable tether connected through the
oxygen functionalities, as demonstrated in 2. This ensures the correct angularly-fused
regiochemistry of the aryne-furan cycloaddition.
[Molecular structure diagrams appear here. To view, please open pdf attachment]. To this end suitable precursors have been examined. After several unsuccessful
attempts at making various suitably-functionalised precursors, double aryne precursor
8 was synthesised and converted into naphthol 10. This was successfully
glycosylated, but this substrate is less flexible later in the synthesis than another substrate developed, 9. This was converted into naphthol 10 and the glycosidation is
currently being optimised. Elsewhere in the group furan 6 has been synthesised. These
systems are appropriate for completing the synthesis of 1. [Molecular structure diagrams appear here. To view, please open pdf attachment].
Date Issued
2011-12
Date Awarded
2012-01
Copyright Statement
Attribution NoDerivatives 4.0 International Licence (CC BY-ND)
Advisor
Barrett, Anthony
Creator
Espensen, George Max
Publisher Department
Chemistry
Publisher Institution
Imperial College London
Qualification Level
Doctoral
Qualification Name
Doctor of Philosophy (PhD)