You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(2S)-N-[(1R)-1-(4-fluorophenyl)ethyl]-6-methyl-4-methylsulfonyl-2,3-dihydro-1,4-benzoxazine-2-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H21FN2O4S
assistant