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-(2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)-4a,5,6,7,8,8a-hexahydro-2H-phthalazin-1-one .
user
C18H23N3O
assistant