methyl (3S,4R,4aS,7S,9aR)-4a-acetoxy-3-formyl-3-methyl-1-oxooctahydro-1H-4,9a-ethanocyclohepta[c]pyran-7-carboxylate

methyl (3R,4R,4aS,7S,9aR)-4a-hydroxy-3-methyl-1-oxo-3-((E)-3-oxoprop-1-en-1-yl)octahydro-1H-4,9a-ethanocyclohepta[c]pyran-7-carboxylate

methyl (3R,4R,4aS,7S,9aR)-4a-hydroxy-3-((E)-3-hydroxyprop-1-en-1-yl)-3-methyl-1-oxooctahydro-1H-4,9a-ethanocyclohepta[c]pyran-7-carboxylate