rac-(1R,2R,3a'R,6a'R)-5'-bromo-3a',4-dimethyl-2-((trimethylsilyl)oxy)-3a',5',6',6a'-tetrahydro-2'H,4'H-spiro[cyclohexane-1,3'-cyclopenta[b]furan]-3-ene-2',4'-dione

(4aR,8aS)-3a-Hydroxy-6,8b-dimethyl-1-oxo-2-phenylsulfanyl-2,3,3a,7,8,8b-hexahydro-1H,4aH-benzo[b]cyclopenta[d]furan-8a-carboxylic acid methyl ester

(3aS,4aS,8aR,8bR)-3a-Hydroxy-6,8b-dimethyl-1-oxo-2,3,3a,7,8,8b-hexahydro-1H,4aH-benzo[b]cyclopenta[d]furan-8a-carboxylic acid methyl ester

(1R*,3R*,7S,8S)-7,11-dimethyl-3-methoxy-8-(methoxycarbonyl)-2-oxa-6-oxotricyclo<6.4.0.03,7>dodec-11-ene

(3aS,4aR,8aS,8bR)-3a-Hydroxy-6,8b-dimethyl-1-oxo-3a,7,8,8b-tetrahydro-1H,4aH-benzo[b]cyclopenta[d]furan-8a-carboxylic acid methyl ester