The first stereoselective total synthesis of euolutchuol C is demonstrated using a biomimetic cationic polyene cyclization, and its absolute structure is established. Four potential stereoisomers of euolutchuol C were synthesized to confirm the structure as an aromatic abietane diterpenoid consisting of a 15(S)-stereogenic center. Asymmetric Sharpless dihydroxylation was employed to build the chiral epoxide, while CBS-reduction was utilized to obtain enantiomerically pure benzylic alcohols. A convergent approach is used to synthesize euolutchuol C in seven longest linear steps resulting in an overall yield of 23 %.

Abstract

The first stereoselective total synthesis of euolutchuol C using a biomimetic cationic polyene cyclization is demonstrated, and its absolute structure has been established. Four potential stereoisomers of euolutchuol C were synthesized to confirm the structure as an aromatic abietane diterpenoid consisting of 15(S)-stereogenic center. Asymmetric Sharpless dihydroxylation was employed to construct the chiral epoxide, while CBS-reduction was utilized for enantiomerically pure benzylic alcohols. A convergent approach is used to synthesize euolutchuol C in seven longest linear steps to give an overall yield of 23 %.