Synthesis of the Macrocyclic Core of Laulimalide

A stereoselective synthesis of <b>3</b>, corresponding to the fully functionalized macrocyclic core of the novel microtubule-stabilizing agent, laulimalide, has been completed. Efficient macrolactonization was achieved by a Mitsunobu reaction, installing the sensitive (<i>Z</i>)-enoate, and macrocyclic stereocontrol was then exploited to introduce the methyl group and <i>trans</i>-epoxide.