You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-ethyl-N-(3-methylphenyl)-2-[5-(4-methylphenyl)-4-oxothieno[2,3-d]pyrimidin-3-yl]acetamide The above is the IUPAC name of a molecule. Write its molecular formula.
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C24H23N3O2S
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