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-[(1-benzylbenzimidazol-2-yl)methyl]-2-[(4-methyl-1,2,5-thiadiazol-3-yl)methylsulfanyl]acetamide using the IUPAC nomenclature.
user
C21H21N5OS2
assistant