You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
N,N-dimethyl-2-[[(2-methylpropylamino)-(spiro[2-oxabicyclo[3.2.0]heptane-7,1'-cyclobutane]-6-ylamino)methylidene]amino]acetamide;hydroiodide is the IUPAC name of a molecule. Please give its molecular formula.
user
C18H33IN4O2
assistant