| Summary: | Many natural products contain a tetramic acid (pyrrolidine-2,4-dione) ring system as an integral part of their structure. They exhibit a wide range of biological activities and are structurally diverse, making them an attractive target for the synthetic chemist. The pyrroindomycin antibiotics are an example of such natural products which contain a spirotetramate core. Studies towards the total synthesis of the pyrroindomycins are described within this thesis, which involve inter- and intra- molecular Diels-Alder approaches towards the synthesis of the spirotetramate core of the natural products. In addition to these synthetic strategies, the relative stereochemistry of the aglycone (previously unknown) was elucidated using NMR spectroscopy, and the findings reported herein. Diels-Alder studies were performed on a model tetramic acid dienophile and the reactivity of this type of system compared to dehydroalanine derivatives. Several spirotetramates were prepared utilising this method, in order to determine if a similar synthetic approach could be used to synthesise the spirotetramate core of the pyrroindomycins. In addition, a spirotetramate was prepared using a nitroalkene dienophile precursor. A number of intramolecular Diels-Alder reactions involving dehydroalanine and nitroalkene dienophiles were also attempted, in order to synthesise a spirotetramate precursor which could be elaborated to the natural products.
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