You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (1R,5S)-6-[(3,5-dimethyl-1,2-oxazol-4-yl)methyl]-3-[(2-methoxyphenyl)methyl]-3,6-diazabicyclo[3.2.2]nonan-7-one .
user
C21H27N3O3
assistant