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 3-[3-oxo-7-[4-[(3-oxopiperazin-1-yl)methyl]triazol-1-yl]-1H-isoindol-2-yl]piperidine-2,6-dione .
user
C20H21N7O4
assistant