You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-[(5S,9R)-3-(3,5-dichlorophenyl)-7-(1H-indol-3-ylmethyl)-1-methyl-2,4-dioxo-1,3,7-triazaspiro[4.4]nonan-9-yl]benzonitrile is the IUPAC name of a molecule. Please give its molecular formula.
user
C29H23Cl2N5O2
assistant