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 2-[4-[2-(benzenesulfonylmethylamino)ethylsulfanyl]-2,6-difluorophenoxy]-N,N-diethylacetamide .
user
C21H26F2N2O4S2
assistant