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 2-(2-bromo-4-phenylphenoxy)-N-(4,5,6,7-tetrahydro-1,3-benzothiazol-2-yl)acetamide into molecular formula.
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C21H19BrN2O2S
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