You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl N-[2-[[N-ethyl-N'-[(3-hydroxy-4-methoxyphenyl)methyl]carbamimidoyl]amino]ethyl]carbamate;hydroiodide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C18H31IN4O4
assistant