You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[3-hydroxy-3-[2-(3-methylphenyl)ethynyl]-8-azabicyclo[3.2.1]octan-8-yl]-2,2-dimethylpropan-1-one The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H27NO2
assistant