Halcinonide Impurity 23

2- ((6aS,6bR,7S,8aS,8bS,11aR,12aS,12bS) -6b-fluoro-7-hydroxy-6a,8a,10,10-tetramethyl-4-oxo-1,2,4,5,6,6a,6b,7,8,8a,11a,12,12a,12b-tetradecahydro-8bH-naphtho[2',1':4,5]indeno[1,2-d][1,3]dioxol-8b-yl) -2-oxoethyl acetate