You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[2-oxo-2-[[(E)-4-[4-(piperidin-1-ylmethyl)pyridin-2-yl]oxybut-2-enyl]amino]ethyl]sulfonylethyl acetate into its molecular formula.
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C21H31N3O6S
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