You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 6-[5-nitro-3-(trifluoromethyl)pyridin-2-yl]oxy-1-[(2,4,6-trifluorophenyl)methyl]quinazolin-4-one is given. What is its corresponding molecular formula?
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C21H10F6N4O4
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