Second-Generation Total Synthesis of Prorocentin.

After a recent total synthesis had resolved all issues surrounding the constitution and stereostructure of prorocentin, it was possible to devise a new approach aiming at an improved supply of this scarce marine natural product; this compound is a cometabolite of the prototypical phosphatase inhibitor okadaic acid but still awaits detailed biological profiling. The revised entry starts from 2-deoxy-d-glucose; keys to success were a telescoped hemiacetal reduction/acetal cleavage and an exquisitely selective gold/Brønsted acid-cocatalyzed spiroacetalization.