You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
7-[(4-fluorophenyl)methyl]-4-hydroxy-1-methyl-8-[(2S)-1-(methylamino)-1-oxopropan-2-yl]oxy-2-oxo-1,5-naphthyridine-3-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H21FN4O5
assistant