You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Convert the IUPAC name of a molecule 1-[[4-(4-ethylpiperazin-1-yl)-3-fluorophenyl]methyl]-2-methyl-3-(3-methylsulfanylcyclopentyl)guanidine;hydroiodide into molecular formula.
user
C21H35FIN5S
assistant