You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl (2S)-3-(carbamoylamino)-2-[[2,6-dichloro-4-[(3-chlorophenyl)methylcarbamoyl]benzoyl]amino]propanoate is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H21Cl3N4O5
assistant