2012 Theses Doctoral

Total Synthesis of Maoecrystal V

Peng, Feng

This thesis describes in detail our journey toward Maoecrystal V, a potential anti-cancer diterpenoid. Maoecrsytal V was isolated in 2004 from a Chinese herbal medicine. It has a highly congested structure, in which there are three continuous quaternary carbon center embedded within a rigid pentacyclic scaffold. The first chapter of this thesis covers the isolation, bioactivity, and synthetic efforts from other groups.

The second chapter discusses our first generation strategy toward Maoecrystal V. During our early studies, we successfully found the conditions for the key intramolecular Diels-Alder reaction. We also identified that the facial selectivity of this Diels-Alder reaction is a big challenge for our synthesis plan. The third chapter describes our solution to the core structure of Maoecrystal V. The exploration resulted in the discovery of a novel exo-glycal epoxide rearrangement. The last chapter describes the total synthesis of Maoecrystal V. The difficulties we met and our solution is discussed.