You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-[6-(1,3-benzodioxol-5-yl)-21-oxo-12,20-dioxa-5,7,8,10-tetrazapentacyclo[11.8.0.03,11.04,8.014,19]henicosa-1(13),3(11),4,6,9,14,16,18-octaen-2-yl]-2-bromo-6-methoxyphenyl] acetate is the IUPAC name of a molecule. Please give its molecular formula.
user
C31H19BrN4O8
assistant