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 2-[5-[(Z)-[3-(2-butoxy-2-oxoethyl)-2,4-dioxo-1,3-thiazolidin-5-ylidene]methyl]furan-2-yl]benzoic acid into molecular formula.
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C21H19NO7S
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