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What is the molecular formula of the compound with this IUPAC name (3aR,6aS)-3-(2-chlorophenyl)-1-(3-methoxyphenyl)-5,5-dioxo-3a,4,6,6a-tetrahydrothieno[3,4-d]imidazol-2-one ?
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C18H17ClN2O4S
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