Total Synthesis of (-)-Lycorine

Significance

Lycorine belongs to the Amaryllidaceae alkaloids. It is a potent emetic. Recently it also emerged as an antiviral agent and apoptosis inductor. The featured step of the synthesis is the formation of the cyclohexane moiety using a chiral ligand-controlled asymmetric cascade conjugate addition to generate two C-C bonds and three stereogenic centers in one pot (A → D). The chiral ligand could be recovered without loss of optical purity.