Corollosporine, a new phthalide derivative from the marine fungus Corollospora maritima Werderm. 1069.

Extracts of the culture medium from the marine fungus Corollospora maritima exhibited concentration dependent antibacterial activity against Staphylococcus aureus and other microorganisms. Bioactivity-guided fractionation and purification afforded the new isobenzofuranone or phthalid type compound corollosporine.