You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule (2,3,5,6-tetrafluorophenyl) 2-[2-[[2-[(2-aminoacetyl)amino]acetyl]amino]ethyl]-4-(2-ethoxyethylsulfanyl)-3-oxobutanoate ?
user
C20H25F4N3O6S
assistant