You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 2-[[6-[4-(4-fluorophenyl)piperazin-1-yl]-5-nitropyrimidin-4-yl]amino]benzoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C23H23FN6O4
assistant