You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
2-[[(2R)-1-cyclopropylsulfonylpiperidin-2-yl]methyl]-6-[5-(difluoromethyl)-1,3,4-oxadiazol-2-yl]-3H-isoindol-1-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H22F2N4O4S
assistant