Total synthesis of (±)-sculponeatin N.

The first total synthesis of the (±)-sculponeatin N (a 6,7-seco-ent-kaurane diterpenoid discovered by Sun and co-workers) has been achieved. The features include a regio- and stereoselective aldol reaction to form a lactone, an intramolecular Diels-Alder reaction to install B and C rings simultaneously, and a radical cyclization to forge the D ring.

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