[(2R,3R,3aS,8bR)-2-(tert-Butyl-diphenyl-silanyloxy)-3-formyl-2,3,3a,8b-tetrahydro-1H-benzo[b]cyclopenta[d]furan-7-yl]-acetic acid methyl ester

{(2R,3R,3aS,8bR)-3-Allyl-7-[2-(2-methoxy-ethoxymethoxy)-ethyl]-2,3,3a,8b-tetrahydro-1H-benzo[b]cyclopenta[d]furan-2-yloxy}-tert-butyl-diphenyl-silane