Synthesis of the C12−C19 Fragment of (+)-Peloruside A through a Diastereomer-Discriminating RCM Reaction

<UFIGR ID="ol050588kn00001">A short and efficient asymmetric synthesis of the C12−C19 fragment of the cytotoxic macrolide (+)-peloruside A has been achieved via a highly diastereomer-discriminating RCM of α-branched but-3-enoate ester of a methallylic alcohol derived from hydrolytically resolved (S)-(−)-propylene oxide.