Asymmetric total synthesis of montanine-type amaryllidaceae alkaloids

Abstract

The first asymmetric total syntheses of (+)-pancratinines B and C and the asymmetric total syntheses of (−)-montanine, (−)-pancracine and (−)-brunsvigine were realized in a divergent fashion. Our synthetic strategy features a copper-catalyzed [3 + 2] annulation reaction, Pictet–Spengler cyclization and an epoxide opening and hydroxyl elimination to form the challenging C1C11a bond.