You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
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Under IUPAC nomenclature, a molecule named (1S,3S,3aR)-1-benzoyl-1,2,3,3a-tetrahydropyrrolo[2,1-b][1,3]benzothiazole-3-carbonitrile is given. What is its corresponding molecular formula?
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C18H14N2OS
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