Synthesis of the C15–C27 fragment of the antitumor agent laulimalide

A stereocontrolled synthesis of the C15–C27 fragment of laulimalide is described. Key features are a divergent–convergent synthesis from (R)-glycidol, an interesting formation of a trisubstituted double bond via ring closing metathesis with Grubbs’ ruthenium catalyst and a site selective protection of a syn-1,2-diol.