You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 6-methyl-5-(4-methylphenyl)-2-[[4-(pyridin-4-ylmethyl)piperazin-1-yl]methyl]-3H-thieno[2,3-d]pyrimidin-4-one is given. What is its corresponding molecular formula?
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C25H27N5OS
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