methyl 1,2,4,6,6a,7,8,9-octahydro-2-methoxy-8,8-dimethylpentaleno<1,6a-c>pyran-5-carboxylate

4',5',6',6'a-tetrahydro-5',5'-dimethyl-3'-<(vinyloxy)methyl>spiro<1,3-dioxolane-2,2'(1'H)-pentalene>

methyl 1,2,4,6,6a,7,8,9-octahydro-8,8-dimethyl-2-oxopentaleno<1,6a-c>pyran-5-carboxylate

((3aR,6aS)-2,2-Dimethyl-4-methylene-5-oxo-hexahydro-pentalen-3a-yl)-acetaldehyde

4',5',6',6'a-tetrahydro-5',5'-dimethylspiro<1,3-dioxolane-2,2'(1H)-pentalene>-3'-methanol