You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[2-oxo-2-(pentan-3-ylamino)ethyl] 2-(3-methoxypropyl)-1,3-dioxoisoindole-5-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H26N2O6
assistant