You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule [7-(dimethylamino)-2,3-dihydro-1,4-benzoxazin-4-yl]-(2-fluoro-4-pyrimidin-5-ylphenyl)methanone .
user
C21H19FN4O2
assistant