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What is the molecular formula of the molecule identified by [(3R,8R,9R,10R,13S,14R,17R)-17-acetyloxy-17-ethynyl-10,13-dimethyl-1,2,3,4,7,8,9,11,12,14,15,16-dodecahydrocyclopenta[a]phenanthren-3-yl] acetate ?
user
C25H34O4
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