You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance 4-[6-[(5-cyclopropylpyrazin-2-yl)amino]-4-methylpyridin-3-yl]-7-fluoro-2,3-dihydroisoindol-1-one .
user
C21H18FN5O
assistant