You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-ethyl-2-[2-(furan-2-yl)-2-hydroxyethyl]-3-[1-[[4-(trifluoromethyl)phenyl]methyl]pyrrolidin-3-yl]guanidine;hydroiodide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H28F3IN4O2
assistant