Total Synthesis of the Marine Antibiotic Pestalone and its Surprisingly Facile Conversion into Pestalalactone and Pestalachloride A

Surprise, surprise! The total synthesis of the marine natural product pestalone (1), a highly substituted benzophenone with strong antibiotic acitivity, has provided insight into the surprising tendency of this and related molecules to undergo intramolecular Cannizzaro–Tishchenko-type reactions. Pestalone can be readily converted into pestalachloride A, a strongly antifungal metabolite isolated from an endophytic fungus, by simple treatment with ammonia at pH 8.