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-chloro-5-methyl-N-[(3-methyl-1,2-oxazol-5-yl)methyl]-2-(3-quinoxalin-2-ylpropoxy)pyrimidin-4-amine into its molecular formula.
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C21H21ClN6O2
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