Stereoselective synthesis of a family of alternating polyols from six-carbon epoxyalkynol modules.

Our new synthetic strategy for assembling polyacetate structures features efficient cross-couplings of six-carbon modules derived from any stereoisomer of the epoxyalkynol derivative (1). Hydration of the internal alkyne in the coupled products and stereoselective reduction of the resulting ketone intermediate provides a general approach to a library of stereoisomeric 1, 3, 5, ... alternating polyols (2). The strategy is demonstrated in a stereoselective synthesis of the C11-C28 polyol substructure of the natural product RK-397.