You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Provide the molecular formula for the IUPAC named substance (2S)-2-[[6-(2-acetamidophenyl)-5-oxo-4H-1,2,4-triazin-3-yl]sulfanyl]-N-(3-chloro-2-methylphenyl)propanamide .
user
C21H20ClN5O3S
assistant