Synthesis of secotrinervitanes, unique bicyclic diterpenes from termites
Abstract
The synthesis of (±)-3α-acetoxy-7,16-secotrinervita-7,11-dien-15β-ol 2, a defence substance of the termite Nastitermes princeps, is fully described. The key step is an intramolecular Dieckmann condensation of substrates 4 and 17, in which an unusually low acidity of the methine proton alpha to the ester carbonyl is observed.