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system
Name the molecular formula for the molecule established as (3aS,6aS)-3-(3-chlorophenyl)-2-[(4-nitrophenyl)methylsulfanyl]-3a,4,6,6a-tetrahydrothieno[3,4-d]imidazole 5,5-dioxide using the IUPAC nomenclature.
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C18H16ClN3O4S2
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