You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 3-tert-butyl-3-azabicyclo[3.1.1]heptane;7-tert-butyl-1-oxa-7-azaspiro[4.4]nonane;methane ?
user
C23H48N2O
assistant