You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (E)-3-[4-(diethylsulfamoyl)phenyl]-N-[3-(1,3,4-oxadiazol-2-yl)phenyl]prop-2-enamide into its molecular formula.
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C21H22N4O4S
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