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system
Name the molecular formula for the molecule established as 1-[1-[3-chloro-5-(trifluoromethyl)pyridin-2-yl]piperidin-4-yl]-3-[(6-methylsulfonylpyridin-3-yl)amino]pyrrolidin-2-one using the IUPAC nomenclature.
user
C21H23ClF3N5O3S
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