You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-methyl-5-[8-methyl-3-(4-methylphenyl)-8-azabicyclo[3.2.1]octan-2-yl]-1,2,4-oxadiazole The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H23N3O
assistant