Total Synthesis of (±)-Euonyminol, the Sesquiterpenoid Nucleus of Cathedulin K-19, via an Epoxide Cascade Cyclization

摘要

A sequence of 19 steps leads from easily accessible 3 and 4 to (±)-euonyminol (2) in which every ring carbon is stereogenic and 11 of the 15 carbons carry an oxygen substituent. The route is potentially applicable to less func-tionalized variants of 2 such as maytoline-and maytine, and efforts to this end as well as toward completion of a synthesis of 1 are in progress.