(-)-(1S,4R,4aS,5R,8aR)-5-tert-Butyldimethylsilyloxy-1,4,4a,6,7,8a-hexahydro-endo-1,4-methanonaphthalen-8(5H)-one

(1R,4S,4aR,8R,8aS)-methyl 8-((tert-butyldimethylsilyl)oxy)-5-hydroxy-1,4,4a,7,8,8a-hexahydro-1,4-methanonaphthalene-6-carboxylate

methyl (1R,5R)-1-acetoxy-5-((tert-butyldimethylsilyl)oxy)-2-oxocyclohex-3-ene-1-carboxylate

methyl (3aR,4S,5R,7R,7aR)-7-((tert-butyldimethylsilyl)oxy)-4,5-dihydroxy-2,2-dimethylhexahydrobenzo[d][1,3]dioxole-5-carboxylate

(1R,4S,4aR,6R,8R,8aS)-methyl 8-((tert-butyldimethylsilyl)oxy)-6-hydroxy-5-oxo-1,4,4a,5,6,7,8,8a-octahydro-1,4-methanonaphthalene-6-carboxylate