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 N-(3-chloro-4-fluorophenyl)-4-[5-(furan-2-ylmethylidene)-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]butanamide into molecular formula.
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C18H14ClFN2O3S2
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