You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule (2R)-2-[(5E)-5-[[5-(4-methoxyphenyl)furan-2-yl]methylidene]-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]-4-methylsulfanylbutanoic acid into molecular formula.
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C20H19NO5S3
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