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What is the molecular formula of the compound with this IUPAC name 2-bromo-1-[(3R,5S,8R,9R,10S,13S,14S,17S)-3-hydroxy-3-(hydroxymethyl)-13-methyl-2,4,5,6,7,8,9,10,11,12,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-17-yl]ethanone ?
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C21H33BrO3
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