You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Convert the IUPAC name of a molecule [(4aR,6R,7R,7aS)-2,2-ditert-butyl-6-(5-methyl-2,4-dioxopyrimidin-1-yl)-4a,6,7,7a-tetrahydro-4H-thieno[3,2-d][1,3,2]dioxasilin-7-yl] acetate into molecular formula.
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C20H32N2O6SSi
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