You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-[5-chloro-2-(1-methylimidazol-2-yl)sulfanylphenyl]-5-piperidin-1-ylsulfonylfuran-2-carboxamide into molecular formula.
user
C20H21ClN4O4S2
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