You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name [3-bromo-4-(6-ethyl-7,10-dihydroxy-2,4-dimethyl-1,3-dioxopyrimido[4,5-c]isoquinolin-8-yl)phenyl] thiohypochlorite into its molecular formula.
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C21H17BrClN3O4S
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