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What is the molecular formula of the compound with this IUPAC name (8S,9R,10S,13R,14R,17S)-17-ethynyl-13-methyl-2,3,6,7,8,9,10,11,12,14,15,16-dodecahydro-1H-cyclopenta[a]phenanthren-17-ol ?
user
C20H28O
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