You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named 4-[methyl-[3-(4-methyl-1,3-thiazol-2-yl)-2-oxochromen-7-yl]amino]butane-1-sulfonic acid is given. What is its corresponding molecular formula?
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C18H20N2O5S2
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