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 (7R)-4-(4-chlorophenyl)-3-(2-methoxyphenyl)-3-aza-1-azonia-2-azanidabicyclo[3.3.0]oct-4-en-7-ol .
user
C18H18ClN3O2
assistant