You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 2-[2-(3-ethylsulfanylbenzoyl)imino-6-methoxy-1,3-benzothiazol-3-yl]acetate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H22N2O4S2
assistant