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system
What is the molecular formula of the compound with this IUPAC name (8S,9S,10R,13S,14S)-17-(2-hydroxyethylidene)-10,13-dimethyl-7,8,9,11,12,14,15,16-octahydro-6H-cyclopenta[a]phenanthren-3-one ?
user
C21H28O2
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