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-(2,3-dihydro-1-benzofuran-2-ylmethyl)-2-methyl-3-[4-(4-methylpiperidin-1-yl)butyl]guanidine into molecular formula.
user
C21H34N4O
assistant