You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule N-[3-chloro-4-(2-methylpropoxy)phenyl]-2,4-dioxo-1-propylpyrido[2,3-d]pyrimidine-6-carboxamide into molecular formula.
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C21H23ClN4O4
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