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What is the molecular formula of the molecule (3R,5R,8R,9R,10S,13S,14R)-3-acetyl-3-hydroxy-10,13-dimethyl-1,2,4,5,6,8,9,11,12,14,15,16-dodecahydrocyclopenta[a]phenanthrene-7,17-dione ?
user
C21H30O4
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