Carijenone, a novel class of bicyclic prostanoid from the eastern Pacific octocoral Carijoa multiflora

An unprecedented biogenetically interesting bicyclic prostanoid 1, carijenone, has been isolated from the eastern Pacific octocoral Carijoa multiflora. The C-12 oxygenated function, characteristic of the coral cyclopentanone fatty acid derivatives, is involved in the formation of a five-membered oxane ring fused to the cyclopentane network. Its structure and stereochemistry were determined on the basis of spectral studies and molecular mechanics calculations.