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 (3S,7aS)-N-(2,6-diethylphenyl)-7a-methyl-5-oxo-2,3,6,7-tetrahydropyrrolo[2,1-b][1,3]thiazole-3-carboxamide into its molecular formula.
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C18H24N2O2S
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