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 5-[4-[4-(benzenesulfonyl)butyl]-2-hydroxyphenyl]-1,1-dioxo-2H-1,2,5-thiadiazol-3-ol into molecular formula.
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C18H20N2O6S2
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