Cymatherelactone and cymatherols A−C, polycyclic oxylipins from the marine brown alga Cymathere triplicata

► Four oxylipins were isolated from the marine brown alga Cymathere triplicata. ► The structures were elucidated by spectroscopic data analyses and derivatization. ► These metabolites are cyclopentyl- and cyclopropyl-containing oxylipins. ► Cymatherelactone and synthetic derivatives showed Na+ channel blocking activities.