Bicyclo[2.2.1]heptan-2-one,3-[3-[[(1,1-dimethylethyl)diphenylsilyl]oxy]-1-hydroxypropyl]-7-ethenyl-5-(6E)-6-octenyl-7-[(triethylsilyl)oxy]-6-[2-[(triethylsilyl)oxy]ethyl]-,(1R,3S,4R,5R,6R,7R)-rel-