You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named ethyl (4R)-6-[[(E)-3-(3,5-dimethoxyphenyl)prop-2-enoyl]oxymethyl]-4-ethyl-2-oxo-3,4-dihydro-1H-pyrimidine-5-carboxylate by IUPAC nomenclature, provide its molecular formula.
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C21H26N2O7
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