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-(2,5-dimethylphenyl)-2-[6-methyl-2-(4-methylpiperidin-1-yl)pyrimidin-4-yl]oxyacetamide into molecular formula.
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C21H28N4O2
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