Studies toward the total synthesis of Azaspiracid 1

A synthetic approach to the C1--C20 portion of the initially proposed structure of Azaspiracid 1 is described. The monoanomeric bisspiroketal configuration is controlled via a metal chelate between the CL hydroxyl and the C13--C17 pyran oxygen. The convergent synthesis strategy relied on a modified Julia-Kocienski olefination to append the C1--C4 sidechain and an acetylide as a two-carbon linker to join the C1--C10 and C13--C20 regions. Key stereoselective transformations include a homoaldol addition, a directed reduction, a cyclic acetal reduction, and an acyclic alkylation. Construction of the C1--C 10 and C13--C20 portions began from copper-catalyzed asymmetric hetero-Diels-Alder and ene reactions, respectively.*; *Please refer to dissertation for diagrams.