You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[6-[6-(2-methoxyethoxy)-3H-isoindol-1-yl]pyrimidin-4-yl]-1-methylpiperazin-2-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H23N5O3
assistant