You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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2-[[2-(5,6-dimethyl-4-oxo-3-propan-2-ylthieno[2,3-d]pyrimidin-2-yl)sulfanylacetyl]amino]-N-methylacetamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H22N4O3S2
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