You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-(4-bromo-3-methyl-1,2-oxazol-5-yl)-3-[2-(6-methyl-1,3-benzodioxol-5-yl)ethyl]-2H-thiophene-3-sulfonamide into molecular formula.
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C18H19BrN2O5S2
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