You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-(1,3-benzodioxol-5-ylmethyl)-1-ethyl-3-[3-(4-ethylpiperazin-1-yl)-2-methylpropyl]guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H35N5O2
assistant