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 4-N-[2-bromo-4-(trifluoromethyl)phenyl]-2-N-ethyl-6-pyridin-4-ylpyrimidine-2,4-diamine into molecular formula.
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C18H15BrF3N5
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