((3aS,4S,5aR,5bS,9aR,10aR,10bR)-2,2,7,7-Tetramethyl-octahydro-1,3,5,6,8,10-hexaoxa-cyclopenta[a]fluoren-4-yl)-acetic acid ethyl ester

((2R,3S,3aS,4aS,7S,8aR,9S,9aS)-3,9-Dihydroxy-2-trityloxymethyl-decahydro-furo[3,2-b]pyrano[2,3-e]pyran-7-yl)-acetic acid methyl ester