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What is the molecular formula of the compound with this IUPAC name [2-(difluoromethylsulfonyl)phenyl]-[4-[5-(5-ethyl-1,2,4-oxadiazol-3-yl)pyridin-2-yl]piperazin-1-yl]methanone ?
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C21H21F2N5O4S
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