You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-[[2-(4-methylsulfonylphenoxy)-5-(pyrazin-2-ylamino)phenyl]methyl]pyrrolidin-1-yl]ethanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C24H26N4O4S
assistant