You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-(3-bromo-4-hydroxy-5-methoxyphenyl)-4-hydroxy-1-(1,3,4-thiadiazol-2-yl)-3-(thiophene-2-carbonyl)-2H-pyrrol-5-one by IUPAC nomenclature, provide its molecular formula.
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C18H12BrN3O5S2
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