(Z)-7-[(5R,6S)-5-[(E,3S)-3-hydroxyoct-1-enyl]-3-oxabicyclo[2.2.1]heptan-6-yl]hept-5-enoic acid D8174_SIGMA 9,11-Dideoxy-11alpha,9alpha-epoxymethanoprostaglandin F2alpha