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 (3aS,6aR)-2-(4-ethoxyphenyl)sulfonyl-1,3,4,5,6,6a-hexahydrocyclopenta[c]pyrrole-3a-carboxylic acid into its molecular formula.
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C16H21NO5S
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