A concise and enantioselective approach to the total synthesis of (−)-lasubine I

An efficient, enantioselective total synthesis of (−)-lasubine I (1) has been achieved in an overall 8.8% yield from readily available starting materials. The important features of this approach include the creation of stereogenic centers through two sequential highly stereoselective Roush allylborations and the use of SN2 cyclization and ring-closing metathesis reactions for the construction of the quinolizidine skeleton.