You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule 3-chloro-4-ethoxy-N-[(2R)-1-oxo-3-phenyl-1-pyrrolidin-1-ylpropan-2-yl]benzenesulfonamide .
user
C21H25ClN2O4S
assistant