You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (2S)-3-[(3S)-1-[(2-chlorophenyl)methyl]-2-oxo-4,5-dihydro-3H-1-benzazepin-3-yl]-2-(methylamino)propanamide .
user
C21H24ClN3O2
assistant