You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-ethyl-1-methyl-2-[[2-(4-methylpiperazin-1-yl)sulfonylphenyl]methyl]-1-[(2-methyl-1,2,4-triazol-3-yl)methyl]guanidine is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H32N8O2S
assistant