Toshifumi Hirukawa

The first synthesis of (±)-3α-acetoxy-15β-hydroxy-7,16-seco-trinervita-7,11-diene, defense substance from a termite soldier

Abstract The first total synthesis of defense substance from a termite soldier has been achieved in a route that allows the preparation of other stereoisomers.

A biogenetic synthesis of (±)-secotrinerviten-2β,3α-diol

Based on biogenetic considerations, (±)-secotrinerviten-2β,3α-diol was synthesized from acetyl epoxy dehydromukulol (4c) by the action of BF3·Et2O.

First synthesis of the trinervitane system from secotrinervitane by transannular ring construction

The unique skeleton of the tricyclic diterpene, trinervitane, was synthesized for the first time in racemic form by a transannular cyclization of a secontrinervitane derivative.

Synthesis of secotrinervitanes, unique bicyclic diterpenes from termites

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.