You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 2-[2-[2-[[5-bromo-1-(sulfomethyl)thieno[3,2-d][1,3]oxazol-2-ylidene]methyl]but-1-enyl]-5-chloro-1,3-benzothiazol-3-ium-3-yl]acetic acid into its molecular formula.
user
C20H17BrClN2O6S3+
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