Deflazacort Impurity 10

2- ((2R,6aR,6bS,7S,8aS,8bS,11aR,12aS,12bS) -2,7-dihydroxy-6a,8a,10-trimethyl-4-oxo-1,2,4,6a,6b,7,8,8a,11a,12,12a,12b-dodecahydro-8bH-naphtho[2',1':4,5]indeno[1,2-d]oxazol-8b-yl) -2-oxoethyl acetate