Rhizoxin synthetic studies. 1. Synthesis of the right hand [C(1) to C(9)]portion via a “pinwheel” approach

A concise synthetic approach to the C(1) C(9) fragment of the antitumor macrolide rhizoxin via a three-fold pseudosymmetric intermediate is described. The preparation (from readily available gamma-butyrolactone) includes both an asymmetric allylation and an asymmetric aldol addition. The pseudosymmetry proved useful in the realization of the target (4).