You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl 4-[[(4S)-3-(4-fluorophenyl)-4-methyl-2,5-dioxoimidazolidin-1-yl]methyl]piperazine-1-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H27FN4O4
assistant