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 2-O-benzyl 3-O-tert-butyl (1S,2S,5R)-4-oxo-3-azabicyclo[3.1.0]hexane-2,3-dicarboxylate into its molecular formula.
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C18H21NO5
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