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What is the molecular formula of the molecule identified by (3S,8S,9R,10R,13S,14R,17S)-17-amino-17-[(1S)-1-hydroxyethyl]-10,13-dimethyl-1,2,3,4,7,8,9,11,12,14,15,16-dodecahydrocyclopenta[a]phenanthren-3-ol ?
user
C21H35NO2
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