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system
What is the molecular formula of the molecule identified by 1-[(3S,8R,9R,10R,13S,14S,15R,17R)-3,15,17-trihydroxy-10,13-dimethyl-1,2,3,4,7,8,9,11,12,14,15,16-dodecahydrocyclopenta[a]phenanthren-17-yl]ethanone ?
user
C21H32O4
assistant