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 2-[2-methoxy-4-[(E)-[(6-methyl-5-oxo-4H-1,2,4-triazin-3-yl)hydrazinylidene]methyl]phenoxy]-N-(4-methylphenyl)acetamide into its molecular formula.
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C21H22N6O4
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