You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[1-[5-(furan-2-yl)-4-oxo-3H-thieno[2,3-d]pyrimidin-2-yl]ethylsulfanyl]-N-(thiophen-2-ylmethyl)acetamide by IUPAC nomenclature, provide its molecular formula.
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C19H17N3O3S3
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