You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
6-[(2S)-1-(4-bromophenyl)-1-oxopropan-2-yl]-1-methylimidazo[1,2-a][1,3,5]triazine-2,4-dione is the IUPAC name of a molecule. Please give its molecular formula.
user
C15H13BrN4O3
assistant