You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-butyl-N-[2-(3-chloro-2-methylanilino)-2-oxoethyl]-2-(4-methoxyphenyl)-5-oxopyrrolidine-3-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H30ClN3O4
assistant