Construction of the tricyclic core of steenkrotin-type diterpenoids via intramolecular [3 + 2] cycloaddition.

ABSTRACT

A concise and diastereoselective route to the angularly fused [5-6-7] tricyclic carbon framework of the steenkrotin-type diterpenoids was reported. The key features of the strategy are based on an intramolecular nitrile oxide/alkene [3 + 2] cycloaddition and a regio-selective aldol/dehydration sequence.