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 N,N-diethyl-2-(3-ethyl-4-oxothieno[3,2-d]pyrimidin-2-yl)sulfanyl-2-phenylacetamide into its molecular formula.
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C20H23N3O2S2
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