You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as N-[(1R,2R)-2-methoxyspiro[1,2-dihydroindene-3,4'-piperidine]-1-yl]-2-pyridin-3-ylacetamide using the IUPAC nomenclature.
user
C21H25N3O2
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