You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2,4-dimethyl-6-[2-[5-(4-methylphenyl)-4-oxothieno[2,3-d]pyrimidin-3-yl]propanoyl]-1,4-benzoxazin-3-one by IUPAC nomenclature, provide its molecular formula.
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C26H23N3O4S
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