You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-(4-hydroxybutyl)-1-(2-methylphenyl)-3-[(4-nitrophenyl)methyl]-4,6-dioxo-1,2,3a,6a-tetrahydropyrrolo[3,4-c]pyrrole-3-carboxylic acid The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H27N3O7
assistant