4-Oxabicyclo[14.1.0]heptadecane-5,9-dione,7,11-bis[[(1,1-dimethylethyl)dimethylsilyl]oxy]-8,8,10,12-tetramethyl-3-[(1E)-1-methyl-2-[5-[(triphenylmethoxy)methyl]-2-pyridinyl]ethenyl]-,(1S,3S,7S,10R,11S,12S,16R)-