You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule N-[[4-chloro-3-[4-(3-fluorophenyl)-6-oxo-1,3-diazinan-2-yl]phenyl]methyl]-2-methylpropanamide ?
user
C21H23ClFN3O2
assistant