You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
1-[2-(3-ethyl-1,2,4-triazol-4-yl)ethyl]-3-[1-(2-methoxy-5-methylphenyl)ethyl]-2-(2-methylprop-2-enyl)guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C21H32N6O
assistant