Acetic acid (R)-2-[(1R,2S)-2-(tert-butyl-diphenyl-silanyloxymethyl)-1-methyl-5-oxo-cyclopentyl]-1-((3aS,5aR,6S,9aS,9bR)-5a-hydroxymethyl-2,2-dimethyl-5,8-dioxo-decahydro-naphtho[1,2-d][1,3]dioxol-6-yl)-ethyl ester

Acetic acid (R)-2-[(1R,2S)-2-(tert-butyl-diphenyl-silanyloxymethyl)-1-methyl-5-oxo-cyclopentyl]-1-((3aS,5aR,6S,9aS,9bR)-5a-formyl-2,2-dimethyl-5,8-dioxo-decahydro-naphtho[1,2-d][1,3]dioxol-6-yl)-ethyl ester

Acetic acid (R)-2-[(1R,2S)-2-(tert-butyl-diphenyl-silanyloxymethyl)-1-methyl-5-oxo-cyclopentyl]-1-((3aS,5S,5aR,6S,9aS,9bR)-5-hydroxy-5a-hydroxymethyl-2,2-dimethyl-8-oxo-decahydro-naphtho[1,2-d][1,3]dioxol-6-yl)-ethyl ester

(R)-2-((1R,2S)-2-(((tert-butyldiphenylsilyl)oxy)methyl)-1-methyl-5-oxocyclopentyl)-1-((4S,4aR,8aS,9aS,12aR,12bS)-7,7,11,11-tetramethyl-2-oxooctahydro-2H,5H-[1,3]dioxolo[4',5':3,4]naphtho[1,8a-d][1,3]dioxin-4-yl)ethyl acetate