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 5-[2-(1-propan-2-ylsulfonylpyrrolidin-3-yl)oxyphenyl]-3-pyrazin-2-yl-1,2,4-oxadiazole .
user
C19H21N5O4S
assistant