You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 5-methyl-2-(1-methylimidazol-2-yl)-6-(1-propan-2-ylpyrazol-3-yl)-3H-thieno[2,3-d]pyrimidin-4-one by IUPAC nomenclature, provide its molecular formula.
user
C17H18N6OS
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