Short synthesis of (+)-cylindricine C and formal total synthesis of (-)-lepadiformine

A short synthesis of (+)-cylindricine C (1c) and a formal total synthesis of (-)-lepadiformine (2) were achieved. The key strategy for the syntheses was a catalytic asymmetric Michael reaction using a two-center organocatalyst (11) (TaDiAS: Tartrate-derived Di-Ammonium Salt) and tandem cyclization to construct the tricyclic ring system.