You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl 5-[(5-bromo-2-chlorobenzoyl)amino]-3-(4-chlorophenyl)-4-oxothieno[3,4-d]pyridazine-1-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H14BrCl2N3O4S
assistant