You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N-[4-chloro-3-(diethylsulfamoyl)phenyl]-4-fluoro-3-(methoxymethyl)-1-benzothiophene-2-carboxamide is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H22ClFN2O4S2
assistant