You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-(4-chloro-2-methylphenyl)iminoethylamino]sulfanyl-N-ethyl-4-methylbenzenesulfonamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H22ClN3O2S2
assistant