You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule N-tert-butyl-2-(1,3-dimethyl-2,4-dioxopyrido[2,3-d]pyrimidin-5-yl)sulfanylacetamide into molecular formula.
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C15H20N4O3S
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