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 3-(3,3-dimethyl-2-bicyclo[2.2.1]heptanyl)-1-[4-(2-nitrophenyl)piperazin-1-yl]propan-1-one .
user
C22H31N3O3
assistant