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What is the molecular formula of the compound with this IUPAC name (8R,9R,10R,13S,14R,17R)-17-acetyl-10,13-dimethyl-1,2,6,7,8,9,11,12,14,15,16,17-dodecahydrocyclopenta[a]phenanthren-3-one ?
user
C21H30O2
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