You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[2-chloro-4-methoxy-6-[[2-(methoxymethyl)-7-methylquinoxalin-5-yl]methylsulfanyl]phenyl]methanimine The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H20ClN3O2S
assistant