Sesquiterpenes and geranylgeranylglycerol from the brown algae Taonia lacheana and Taonia atomaria f. ciliata: their chemotaxonomic significance

Taonia lacheana is a very recent addition to the small Taonia genus. The chemical composition of the new species is characterized by the presence of aromadendrane sesquiterpenes [(+)-spathulenol, (+)-11-epispathulenol and(-)-7,1l-dihydroxyaromadendrane] and(-)-(R)-1-geranylgeranylglycerol. A related species from which the last compound had been previously isolated, misidentified as Dilophus fasciola and now recognized to be T. atomaria f. ciliata, has been re-investigated confirming the absence of aromadendrane derivatives. The two Mediterranean Taonia species differ sharply from the Canarian T. atomaria, that is known to elaborate meroditerpenoids.