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system
Name the molecular formula for the molecule established as 8-[3-[(1S,4R)-2-azabicyclo[2.2.1]heptan-2-yl]propanoyl]-3-(3-methylbutyl)-1-oxa-3,8-diazaspiro[4.5]decan-2-one using the IUPAC nomenclature.
user
C21H35N3O3
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