(1R,3aR,5aS,6R,8aR)-6-(4-Methoxy-benzyloxy)-1,7,7-trimethyl-octahydro-cyclopenta[c]pentalen-4-one

(6R,6aS)-6-Benzyloxy-5,5-dimethyl-3-trimethylsilanyl-4,5,6,6a-tetrahydro-1H-pentalen-2-one

{(E)-(R)-3-[(1R,3aR,6aS)-1-(4-Methoxy-benzyloxy)-2,2-dimethyl-5-oxo-hexahydro-pentalen-3a-yl]-but-1-enyl}-phosphonic acid diethyl ester