You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Translate the chemical IUPAC name methyl (5S,6R,7aS)-2'-oxospiro[3,6,7,7a-tetrahydro-1H-pyrrolo[1,2-c][1,3]thiazole-5,1'-acenaphthylene]-6-carboxylate into its molecular formula.
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C19H17NO3S
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