You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (2R)-2-[3-[(5E)-5-benzylidene-4-oxo-2-sulfanylidene-1,3-thiazolidin-3-yl]propanoylamino]pentanoic acid is given. What is its corresponding molecular formula?
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C18H20N2O4S2
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