New brominated C)g acetylenic acids and methyl esters (3.5,9-10;12-17) have heen isolated from the marine sponge, Perrosin volcano Hoshino. Their structures were determined by spectroscopic methods as well as comparison of spectral data with those of known related metabolites. Both acetylenic acids and their methyl esters exhibited activity against the fungus Mortierella ramantum.
Sponges of the orders Nepheliospongida and Haplosclerida often elaborate acetylenic metabolites including polyacetylenes.2 acetylenic glyceryl ethers,3 and brominated acetylenic acids,4 which show a variety of biological activities, e.g. antimicrobial, cytotoxic, ichthyotoxic. H, K-ATPase inhibitory and HIV protease inhibitory. In the course of our studies on hioactive metabolites from Japanese marine invertebrates,1 the marine sponge, Petrosio volcano Hoshino, ml&ted off Hachijo-jima Island, showed antifungal activity. Bioassay-guided isolation afforded ten new brominated acetylenic acids (3,5,9-10.12-17).
together with the known xestospongic acid (1)4a and l&bromo-(9E,
17.E')~octadeca-9,17diene-5,7,15-niynoic acid (7).4c* 4f This paper deals with the isolation and structure elucidation of the new compounds.
The ether and n-butanol soluble portions of the ethanol extract of the frozen sponge (800 g) were fractionated by silica gel, ODS flash, and ODS medium pressure column chromatographies, followed by repeated ODS HPLC to afford