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 3-[[(2'S,3S,4'R)-2'-(2,2-dimethylpropyl)-6-methyl-4'-phenylspiro[2H-indole-3,3'-pyrrolidine]-1-yl]methyl]benzoic acid .
user
C31H36N2O2
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