Toluene-4-sulfonic acid (S)-2-(tert-butyl-dimethyl-silanyloxy)-1-{(2R,5R,2'R,5'R)-5'-[(S)-2-(tert-butyl-dimethyl-silanyloxy)-1-hydroxy-ethyl]-octahydro-[2,2']bifuranyl-5-yl}-ethyl ester

Acetic acid (S)-2-[(2R,5R,2'R,5'R)-5'-((R)-1-acetoxy-undec-3-ynyl)-octahydro-[2,2']bifuranyl-5-yl]-2-(toluene-4-sulfonyloxy)-ethyl ester

Toluene-4-sulfonic acid (S)-2-(tert-butyl-dimethyl-silanyloxy)-1-{(2R,5R,2'R,5'R)-5'-[(S)-2-(tert-butyl-dimethyl-silanyloxy)-1-methoxymethoxy-ethyl]-octahydro-[2,2']bifuranyl-5-yl}-ethyl ester