You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[5-(4-ethylphenyl)-4-methyl-1,1,3-trioxo-1,2-thiazol-2-yl]-N-(3-methylsulfanylphenyl)acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22N2O4S2
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