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 5-methyl-4-oxo-3-[2-oxo-2-(4-propan-2-yloxyanilino)ethyl]thieno[2,3-d]pyrimidine-6-carboxylate into its molecular formula.
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C21H23N3O5S
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