You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 2-[(1,3-dimethyl-2,6-dioxo-7H-purin-8-yl)sulfanyl]-N-(4-methoxyphenyl)acetamide by IUPAC nomenclature, provide its molecular formula.
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C16H17N5O4S
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