You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-(4-chlorophenyl)-2-nitrophenyl] N-[2-[6-(4-methylpiperazin-1-yl)pyridin-3-yl]ethyl]carbamate is the IUPAC name of a molecule. Please give its molecular formula.
user
C25H26ClN5O4
assistant