Dexamethasone Impurity 17

Chemical Name: (8S,9R,10S,11S,13S,14S,16R,17R)-9-fluoro-11,17-dihydroxy-10,13,16-trimethyl-3-oxo-6,7,8,9,10,11,12,13,14,15,16,17-dodecahydro-3H-cyclopenta[a]phenanthrene-17-carbaldehyde

Synonym: (3R,3aR,6aS)-hexahydrofuro[2,3-b]furan-3-yl (4-nitrophenyl) carbonate