A new approach to the pseudomonic acid skeleton

This thesis commences with a brief account of the discovery and biological action of the pseudomonic acids followed by a comprehensive review of the chemistry and synthetic work published on pseudomonic acid C (1.0.3) to date. An outline of our intended approach to pseudomonic acid C is followed by a detailed account of our actual synthesis of the central fragment (1.24.1), 'left hand' fragment (1.24.2) and 'right hand' fragment (1.24.3) together with a full account of our attempts to couple said fragments, including the planned benzothiazole olefination reaction to unite (1.24.1) and (1.24.2) which gave only modest stereoselectivity.Ultimately the carbohydrate nucleus (1.7.4) was completed in eight sequential steps having the cobalt catalysed siloxymethylation reaction as the key step. The 'left hand' side was eventually attached to the tricyclic epoxide (1.7.4) by means of a Grignard reaction as previously described by Sinay.The 'right hand' fragment (1.24.3) was secured in four steps having the stannyl cupration of acetylenic ester (1.24.4) as the key step. Union of vinyl stannane (1.24.3) with the central fragment (4.9.3) was achieved, after an involved oxidation procedure of the C4 oxygen moiety, via a palladium catalysed cross coupling reaction.