You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
4-(3-ethyl-1,2,4-thiadiazol-5-yl)-N-(3-indol-1-ylpropyl)-N'-methylpiperazine-1-carboximidamide;hydroiodide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C21H30IN7S
assistant