You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[(E)-[3-(2,3-dimethylphenyl)-4-oxo-2-sulfanylidene-1,3-thiazolidin-5-ylidene]methyl]benzoic acid is the IUPAC name of a molecule. Please give its molecular formula.
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C19H15NO3S2
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