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What is the molecular formula of the molecule identified by 2,2-dimethylpropanoyloxymethyl 6-(1-hydroxyethyl)-4-methyl-7-oxo-3-(5-oxopyrrolidin-3-yl)sulfanyl-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylate ?
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C20H28N2O7S
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