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

An investigation of the oxylipin chemistry of the temperate brown alga Cymathere triplicata led to the isolation of several secondary metabolites, cymatherelactone (1) and cymatherols A-C (2-4), the latter as their methyl ester derivatives (5-7), which contained cyclopentyl, cyclopropyl, epoxide and lactone rings. Their structures were elucidated using a combination of spectroscopic techniques and synthetic chemistry. Cymatherelactone (1), as well as R- and S-Mosher's esters of its seco acid, exhibited moderate sodium channel blocking activity.