You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(2-tert-butylsulfonylethyl)-1-[1-[2-(difluoromethoxy)phenyl]pyrrolidin-3-yl]-3-ethylguanidine;hydroiodide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H33F2IN4O3S
assistant