You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-(6,7-dimethoxyquinazolin-4-yl)-N-methyl-3-[4-(trifluoromethyl)phenyl]-1,2-oxazol-5-amine into molecular formula.
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C21H17F3N4O3
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