You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-(1,1-dioxo-2,3-dihydrothiophen-3-yl)-1-(2-methylthieno[2,3-d]pyrimidin-4-yl)piperidin-4-amine is the IUPAC name of a molecule. Please give its molecular formula.
user
C16H20N4O2S2
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