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 3-(carbamoylamino)-5-[4-[3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxyphenyl]thiophene-2-carboxylic acid into molecular formula.
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C18H20N2O9S
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