Talarolactone A, an Isocoumarin Derivative Fused with Dihydrothiophene with Selective Antimigratory Activity from the Endolichenic Fungus sp.

A 3,4-dihydroisocoumarin derivative fused with dihydrothiophene, talarolactone A (), and two known compounds, terreusinone () and 4,6-dihydroxy-5-methylphthalide (), were isolated from sp. associated with . The structure of was deduced from extensive spectroscopic data, electronic circular dichroism calculations, and X-ray diffraction analyses. A plausible biosynthetic pathway of was further proposed. Compound showed selective antimigratory activity in a wound-healing assay without appreciable cytotoxic activity.