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 [(1S,3S,4S)-3,4-dimethylcyclohexyl] (4R)-4-(2-methoxyphenyl)-6-methyl-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate into molecular formula.
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C21H28N2O4
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