RIGIDONE, A SESQUITERPENE O-QUINONE FROM THE GORGONIAN PSEUDOPTEROGORGIA-RIGIDA

As part of a search for novel biologically active compounds in the Mac rophage Scavenger Receptor (MSR) assay, the EtOAc extract of a gorgoni an coral, Pseudopterogorgia rigida, was shown to be active. Bioassay-g uided fractionation of the extract yielded curcuphenol, curcuhydroquin one, curcuquinone, and a novel o-quinone, rigidone (1). The structure and stereochemistry of 1 was determined by interpretation of spectral data and chemical transformation.