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 2-[2-(4-ethoxyphenyl)-2-oxoethyl]sulfanyl-6-methyl-3-prop-2-enylthieno[2,3-d]pyrimidin-4-one into molecular formula.
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C20H20N2O3S2
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