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Name the molecular formula for the molecule established as ethyl 4-(4-chlorophenyl)-2-oxo-6-[(4-oxothieno[2,3-d]pyrimidin-3-yl)methyl]-3,4-dihydro-1H-pyrimidine-5-carboxylate using the IUPAC nomenclature.
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C20H17ClN4O4S
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