Long chain aldehydes from the red alga Corallina mediterranea

From the red alga, Corallina mediterranea, collected in the Mediterranean Sea, two unusual aldehydes were isolated, (E)-2-tridecyl-2-heptadecenal and the new (2E,4E)-2-tridecyl-2,4-heptadecadienal. The structure of the new metabolite was proposed on the basis of its spectral data.