You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 4-[(1R,2R,5S)-7-benzyl-3,7-diazabicyclo[3.3.1]nonan-2-yl]-N-[2-(1-ethyl-3,5-dimethylpyrazol-4-yl)ethyl]-N-methylbutanamide into molecular formula.
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C28H43N5O
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