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 (3-bromo-2,5-dimethoxyphenyl)-[4-[5-(trifluoromethyl)pyridin-2-yl]-1,4-diazepan-1-yl]methanone .
user
C20H21BrF3N3O3
assistant