You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3,20-dimethyl-15-propan-2-yl-12-oxa-18-aza-20-azoniapentacyclo[11.7.1.02,11.04,9.017,21]henicosa-1(20),2,4,6,8,10,13,15,17(21),18-decaene The above is the IUPAC name of a molecule. Write its molecular formula.
user
C23H21N2O+
assistant