3-Oxo-axisonitrile-3, a new sesquiterpene isocyanide from the Chinese marine sponge Acanthella sp.

A new sesquiterpene isocyanide, 3-oxo-axisonitrile-3 (1), with a spiro [5,6] decane skeleton (spiroaxane) together with a known related sesquiterpene isonitrile (2), sesquiterpene isothiocyanates (3-8) and two diterpene isonitriles (9, 10) have been isolated from the Chinese marine sponge Acanthella sp. The structure of 1 has been determined on the basis of spectroscopic analysis.