You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as N-(4-aminophenyl)sulfanyl-N,1-diethyl-2-(2-methoxypropan-2-yl)benzimidazol-5-amine using the IUPAC nomenclature.
user
C21H28N4OS
assistant