Formal Synthesis of (−)-Kendomycin Featuring a Prins-Cyclization To Construct the Macrocycle

The kendomycin skeleton was prepared by a highly convergent strategy in which the benzofuran fragment and the acyclic iodide fragment were prepared by standard methods and joined using a Suzuki coupling. The distinctive reaction in our approach was an intramolecular Prins cyclization that assembles the macrocyclic ring in good yield. Modeling studies demonstrate that the acyclic chain is predisposed for macrocycle formation. Ultimately, the product was correlated with one of Lee's advanced intermediates for a formal total synthesis of kendomycin.