Total Synthesis of (.+-.)-Kalihinol C.

The total synthesis of kalihinol C, a bis-isonitrile marine diterpenoid isolated from Acanthella sp., is reported. The decalin framework was established via an intramolecular Diels−Alder cycloaddition and subsequently functionalized through a series of substrate-controlled diastereoselective transformations to install the tertiary isonitrile, β-hydroxy isonitrile, and pendant tetrahydrofuranyl ring.