You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
3-[(2S)-2-(furan-2-ylmethyl)-5-oxopyrrolidin-2-yl]-N-[[4-(trifluoromethoxy)phenyl]methyl]propanamide The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H21F3N2O4
assistant