(2E)-(1R,3R,4S,5R)-3-[[(1,1-Dimethylethyl)dimethylsilyl]oxy]-1-hydroxy-7-oxo-6-oxabicyclo[3.2.1]oct-4-yl Ester 3-[4-(Acetyloxy)-3-methoxyphenyl]-2-propenoic Acid