A Short Total Synthesis of the Daucane Sesquiterpenoid Ferutinin

A straightforward total synthesis of the bioactive daucane sesquiterpene ester ferutinin is reported. Starting from 3‐methyl‐2‐cyclopentenone and allyl p ‐tolyl sulfoxide, only nine steps were required to access the target sesquiterpenoid in 22% overall yield. A one‐pot sequential conjugate addition/aldol reaction to set up a trisubstituted cyclopentanone moiety and a ring‐closing metathesis to generate the hydroazulene core were used as the key transformations. Addition of isopropyllithium completed the daucane skeleton and eventually led to the sesquiterpene jaeschkeanadiol. Finally, esterification of this diol gave rise to ferutinin.