You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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For the molecule named (5Z)-5-[(4-hydroxy-3,5-dimethylphenyl)methylidene]-3-phenyl-1,3-thiazolidine-2,4-dione by IUPAC nomenclature, provide its molecular formula.
user
C18H15NO3S
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