You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[4-bromo-2-[(E)-[(3-chlorophenyl)carbamothioylhydrazinylidene]methyl]phenyl] 2-chlorobenzoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H14BrCl2N3O2S
assistant