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What is the molecular formula of the compound with this IUPAC name (6R,7R,8R)-4-ethylsulfonyl-8-(hydroxymethyl)-7-[4-(4-methylpent-1-ynyl)phenyl]-1,4-diazabicyclo[4.2.0]octan-2-one ?
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C21H28N2O4S
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