Total Synthesis of Oidiodendrolides and Related Norditerpene Dilactones from a Common Precursor: Metabolites CJ-14,445, LL-Z1271γ, Oidiolactones A, B, C, and D, and Nagilactorie F

An efficient, high-yielding strategy has been developed for the asymmetric total synthesis of seven norditerpenoid dilactones known for their diverse biological properties. The three key steps employed to obtain a tricyclic lactone intermediate Involved a Morita-Baylis-Hillman reaction, the stereocontrolled construction of a gamma-lactone through bromolactonization, and an efficient catalytic Reformatsky-type reaction. Access to CJ-14,445, LL-Z1271 gamma, oidiolactones A, B, C, and D, and nagilactone F was possible from a common intermediate. Structures and stereochemistry were determined by X-ray analysis.