You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[(9-chloro-6-oxo-5,7-dihydropyrimido[5,4-d][1]benzazepin-2-yl)amino]benzenesulfinate is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H12ClN4O3S-
assistant