You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-methoxyethyl 2-[5-(4-ethoxyphenyl)-2,6-dimethyl-4-oxothieno[2,3-d]pyrimidin-3-yl]propanoate is the IUPAC name of a molecule. Please give its molecular formula.
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C22H26N2O5S
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