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-methyl-N-phenyl-6-[7-(trifluoromethoxy)-3,4-dihydro-1H-isoquinolin-2-yl]pyrimidin-2-amine into molecular formula.
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C21H19F3N4O
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