You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (5R,6S,8R)-6-bromo-2-(4-methylphenyl)sulfonyl-8-phenyl-1,2-diazaspiro[4.5]decan-3-one .
user
C21H23BrN2O3S
assistant