Some Metabolites of the Marine Sponges Smenospongia aurea and Smenospongia (= Polyfibrospongia) echina

The antimicrobial metabolite of the marine sponge Smenospongia aurea was found to be 5-bromo-N,Ar-dimethyltryptamine (4). The same sponge also contained aureol (6), an unusual sesquiterpene-hydroquinone derivative. A second sample of S. aurea contained 8-epichromazonarol (20) and the indole 27. Two samples of Smenospongia echina were examined and were shown to contain the antimicrobial constituent 5,6-dibromo-N-N-dimethyltryptamine (3), with small amounts of the phenol 25 in one sample. The structure of aureol (6) was determined by X-ray analysis while those of the remaining compounds were determined from spectroscopic data, particularly 13C NMR spectra, and chemical interconversions.