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 2-[2-[(Z)-[2-(4-chlorophenyl)imino-4-oxo-3-propyl-1,3-thiazolidin-5-ylidene]methyl]phenoxy]acetic acid into molecular formula.
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C21H19ClN2O4S
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