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 [2-(4-methoxyphenyl)-2-oxoethyl] 2-[(4R)-4-methyl-2,5-dioxo-4-phenylimidazolidin-1-yl]acetate ?
user
C21H20N2O6
assistant