You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule methyl 2-[1-[[4-(2-cyanophenyl)phenyl]methyl]-6-ethyl-2,4-dioxothieno[2,3-d]pyrimidin-3-yl]acetate into molecular formula.
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C25H21N3O4S
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