You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name 6-hydroxy-5-[(3-methyl-4-nitrophenyl)iminomethyl]-1-(2,4,6-trimethylphenyl)pyrimidine-2,4-dione into its molecular formula.
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C21H20N4O5
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