You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
What is the molecular formula of the molecule 5-(1-acetylpiperidin-4-yl)-2-(6-chloro-1H-benzimidazol-2-yl)-4-[2-(triazol-2-yl)ethyl]-1H-pyrazol-3-one ?
user
C21H23ClN8O2
assistant