You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[(3-chlorophenyl)methyl]-2'-oxospiro[1,2,5,6,7,8-hexahydropyrrolizine-3,3'-1H-indole]-2-carboxamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C22H22ClN3O2
assistant