You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Name the molecular formula for the molecule established as (2R)-N-[(2S)-butan-2-yl]-2-[(3-chloro-4-methoxyphenyl)sulfonylamino]-3-phenylpropanamide using the IUPAC nomenclature.
user
C20H25ClN2O4S
assistant