You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as 1-(2-methylpyridin-4-yl)-5,7,8,9-tetrahydro-3H-cyclohepta[f]isoindol-6-one using the IUPAC nomenclature.
user
C19H18N2O
assistant