You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
(4R)-4-benzyl-3-[(3R)-4,4,4-trifluoro-3-(4-fluorophenyl)butanoyl]-1,3-oxazolidin-2-one is the IUPAC name of a molecule. Please give its molecular formula.
user
C20H17F4NO3
assistant