You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule 2,3,4,4a,5,6,7,7a-octahydropyrrolo[3,4-b]pyridin-1-yl-(5-bromopyridin-2-yl)methanone ?
user
C13H16BrN3O
assistant