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 N-[(1-methyl-2-oxo-4,5,6,7-tetrahydro-3H-quinolin-4a-yl)methyl]-4-phenylbutanamide using the IUPAC nomenclature.
user
C21H28N2O2
assistant