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-tert-butyl-2-[3-[(2-methoxyphenyl)methyl]-4-oxothieno[3,2-d]pyrimidin-2-yl]sulfanylacetamide into its molecular formula.
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C20H23N3O3S2
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