You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-(2,5-diethoxyphenyl)-2-[3-(4-methyl-1,3-thiazol-2-yl)propyl]guanidine;hydroiodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H27IN4O2S
assistant