You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 4-[5-[(Z)-(7-methoxy-2,4-dioxo-1,5-dihydropyrimido[5,4-b]indol-3-yl)iminomethyl]furan-2-yl]benzoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H20N4O6
assistant