You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(3,4-dimethoxyphenyl)-N-[5-[2-(4-methylanilino)-2-oxoethyl]sulfanyl-1,3,4-thiadiazol-2-yl]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22N4O4S2
assistant