1H-1,4a-Methanocyclopenta[b]naphtho[2,3-e]pyran-12-carboxaldehyde,2,3,3a,5,10,11a-hexahydro-7-hydroxy-3a,12-dimethyl-5,10-dioxo-,(1S,3aR,4aS,11aS,12S)-rel-(-)-