You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name 4-[5-[[3-(3-fluorophenyl)-4-oxo-2-sulfanylidene-1,3-thiazolidin-5-yl]methyl]furan-2-yl]benzoic acid into its molecular formula.
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C21H14FNO4S2
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