You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 1-[3-(2,6-dimethylpyrimidin-4-yl)oxypiperidin-1-yl]-2-(4-methoxy-3-methylphenyl)ethanone into its molecular formula.
user
C21H27N3O3
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