Total Synthesis of the Antibiotic Elansolid B1

The antibiotic elansolid B1 was prepared by a convergent strategy that relied on a highly diastereoselective, biomimetic intramolecular Diels-Alder cycloaddition (IMDA) that furnished the tetrahydroindane unit. Other key features are a double Sonogashira cross-coupling and a substrate-controlled Yamamoto aldol reaction.