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 3-bromo-N-[(1-methoxypyridin-1-ium-3-yl)methyl]-5-phenylpyrazolo[1,5-a]pyrimidin-7-amine;ethane into molecular formula.
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C21H23BrN5O+
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