You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(3-chloro-4-methoxy-N-methylsulfonylanilino)-N-[(Z)-[4-(2-methylpropoxy)phenyl]methylideneamino]acetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H26ClN3O5S
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