You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
[(2S)-1-(2,6-difluoroanilino)-1-oxopropan-2-yl] 4-(2,5-dimethylthiophen-3-yl)-4-oxobutanoate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C19H19F2NO4S
assistant