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What is the molecular formula of the molecule identified by methyl (4R)-4-[(3R,5R,8R,9S,10S,13R,14S,17R)-3-acetyloxy-10,13-dimethyl-12-oxo-1,2,3,4,5,6,7,8,9,11,14,15,16,17-tetradecahydrocyclopenta[a]phenanthren-17-yl]pentanoate ?
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C27H42O5
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