You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
5-[(4aR,8aR)-1,2,3,4,4a,5,8,8a-octahydroisoquinolin-7-yl]-2-bromopyridine-3-carbonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H16BrN3
assistant