(2aR,4S,4aS,6R,8aS,8bS)-8b-Benzyloxy-4-(tert-butyl-dimethyl-silanyloxy)-6-hydroxy-4a-methyl-octahydro-2-oxa-cyclobuta[a]naphthalen-7-one

Trifluoro-methanesulfonic acid (4S,5S)-4-[(1S,2R,3S,4S,6R)-1-benzyloxy-4-(tert-butyl-dimethyl-silanyloxy)-3-methyl-3-(2-oxo-ethyl)-7-oxa-bicyclo[4.2.0]oct-2-yl]-6,6,8-trimethyl-2-oxo-1,3-dioxa-spiro[4.5]dec-7-en-7-yl ester

(1S,6S)-1-{(S)-[(1S,2R,3S,4S,6R)-1-Benzyloxy-4-(tert-butyl-dimethyl-silanyloxy)-3-(2,2-dimethoxy-ethyl)-3-methyl-7-oxa-bicyclo[4.2.0]oct-2-yl]-hydroxy-methyl}-2,2,4-trimethyl-7-oxa-bicyclo[4.1.0]hept-4-en-3-one