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 (1'S,2'R,3R,3'aR)-1',2'-bis(4-bromobenzoyl)-7'-chlorospiro[1H-indole-3,3'-2,3a-dihydro-1H-pyrrolo[1,2-a]quinoline]-2-one .
user
C33H21Br2ClN2O3
assistant