You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named 4-[(E)-[3-(1,3-benzodioxol-5-yl)-4-oxo-2-sulfanylidene-1,3-thiazolidin-5-ylidene]methyl]benzoic acid by IUPAC nomenclature, provide its molecular formula.
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C18H11NO5S2
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