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 ethyl (4S)-6-(2H-chromene-3-carbonyloxymethyl)-4-ethyl-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate into its molecular formula.
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C20H22N2O6
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