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 N-[1-(2-bicyclo[2.2.1]heptanyl)ethyl]-2-(5-chloro-2-oxo-1,3-benzoxazol-3-yl)acetamide into its molecular formula.
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C18H21ClN2O3
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