2-Propenoicacid, 3-phenyl-,1-[2-[1-(acetyloxy)ethyl]-2-hydroxy-1-methyl-5-oxocyclopentyl]-2-(1,2,3,5,6,7,8,8a-octahydro-6-hydroxy-8a-methyl-2-oxo-1-naphthalenyl)ethylester, stereoisomer