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The Asymmetric synthesis of 2-epi-Prevezol C and the diastereoisomers of Quercivorol

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thesis
posted on 19.01.2017 by Blair, Michael
The brominated secondary metabolites isolated from the polar fractions of the macroalga Laurencia Obtusa (Lamoroux), termed ‘Prevezols’ posses cytotoxic properties against a range of human carcinoma lines. These novel diterpenes contain unique molecular architectures with an incredibly rare and challenging syn-bromohydrin motif, to date unaddressed via total synthesis. This dissertation discloses the synthesis of the diterpene framework of Prevezol C, via a stereoconvergent allylic alkylation strategy of two monoterpene chirons, derived from the optically pure commercial mixture of cis- and trans- limonene oxide. The first part of this thesis is concerned with the separation and isolation of both the cis- and trans-limonene oxide isomers via a hydrolytic kinetic separation, to the corresponding limonene trans- diaxial and -diequatorial diols (Chapter 2), which are implemented as part of the synthesis of the 2-bromo epimer of Prevezol C (Chapter 3, Part 1). A novel free radical hydrodebromination strategy (Chapter 3, Part 2) was successfully employed as a means of accessing the naturally occurring synbromohydrin relationship found in the Eastern domain of the Prevezols, and several other secondary metabolites derived from the red algae species of Laurencia. Finally, a second total synthesis of the major and minor constituents of the ambrosia beetle Platypus quercivorus was also achieved (Chapter 4) via a palladium catalysed deoxygenation strategy of the limonene trans-diaxial and -diequatorial diols.

History

Campus location

Australia

Principal supervisor

Kellie Tuck

Year of Award

2009

Department, School or Centre

Chemistry

Course

Doctor of Philosophy

Degree Type

DOCTORATE

Faculty

Faculty of Science

Exports