You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Can you give the molecular formula of the molecule 5-[(1S,2R,4R)-2-bicyclo[2.2.1]heptanyl]-1,5-dimethyl-3-[2-(3-methylphenyl)-2-oxoethyl]imidazolidine-2,4-dione ?
user
C21H26N2O3
assistant