You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(2S)-2-(2-fluorophenyl)-4-oxo-1,2-dihydroquinazolin-3-yl]-4-methylbenzenesulfonamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H18FN3O3S
assistant