You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (E)-3-[5-(3-chloro-4-methylphenyl)furan-2-yl]-N-[(2-fluoro-5-nitrophenyl)carbamothioyl]prop-2-enamide into molecular formula.
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C21H15ClFN3O4S
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