Toward the synthesis of hirsutellone B via an intramolecular Diels-Alder/ketene-trapping strategy

In this paper, the pentacyclic skeleton of hirsutellone B including the paracyclophane was constructed via a tandem IMDA/ketene-trapping scenario with the proper stereochemistry. Alternatively, from the common intermediate 4, we completed a formal synthesis of hirsutellone B.