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 methyl 3-[[3-methyl-4-oxo-5-(pyridin-4-ylmethylidene)-1,3-thiazolidin-2-ylidene]amino]benzoate into molecular formula.
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C18H15N3O3S
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