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 N-methyl-2-[4-(2-oxopyrrolidin-1-yl)phenyl]sulfonyl-3,4-dihydro-1H-isoquinoline-3-carboxamide .
user
C21H23N3O4S
assistant