You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(Z)-(2-bromo-4-hydroxyphenyl)-(2-bromo-4-oxoniumylidenecyclohexa-2,5-dien-1-ylidene)methyl]benzenesulfonate is the IUPAC name of a molecule. Please give its molecular formula.
user
C19H12Br2O5S
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