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-(6-bromo-2,3-dihydro-1,4-benzodioxin-7-yl)-N-[4-(3,4-dimethoxyphenyl)-1,3-thiazol-2-yl]acetamide by IUPAC nomenclature, provide its molecular formula.
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C21H19BrN2O5S
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