You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Translate the chemical IUPAC name (3S,7aR)-7a-(4-methylphenyl)-5-oxo-2,3,6,7-tetrahydropyrrolo[2,1-b][1,3]thiazole-3-carboxylic acid into its molecular formula.
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C14H15NO3S
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