Cacolides: Sesterterpene Butenolides From A Southern Australian Marine Sponge, Cacospongia Sp.

Chemical analysis of a marine sponge, Cacospongia sp. (CMB-03404), obtained during deep sea commercial fishing activities off the southern coast of Australia, yielded an unprecedented family of sesterterpene -methyl--hydroxybutenolides, cacolides A-L (1-12), together with biosynthetically related norsesterterpene carboxylic acids, cacolic acids A-C (13-15). Structures were assigned on the basis of detailed spectroscopic analysis with comparisons to known natural products and biosynthetic considerations. In addition to revealing new chemical diversity, this study provided a valuable platform for comparing and contrasting the capabilities of the traditional dereplication technologies of HPLC-DAD, HPLC-MS and NMR, with those of the emerging HPLC-MS/MS approach known as global natural products social molecular networking (GNPS), as applied to marine sponge sesterterpene tetronic acids.