You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-butyl-N-(1,1-dioxothiolan-3-yl)-2-[2-oxo-5-(trifluoromethyl)pyridin-1-yl]acetamide into molecular formula.
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C16H21F3N2O4S
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