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 3-[(5-ethyl-3-methoxycarbonylthiophen-2-yl)carbamoyl]bicyclo[2.2.2]octane-2-carboxylic acid is given. What is its corresponding molecular formula?
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C18H23NO5S
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