You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[3-[3-amino-5-(difluoromethyl)-1,1-dioxo-6,7-dihydro-2H-1,4-thiazepin-5-yl]-4-fluorophenyl]-1-(5-isocyanopyridin-2-yl)ethanone The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H17F3N4O3S
assistant