You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
ethyl (3R)-1-ethylsulfonyl-3-[[(5S)-3-(4-fluorophenyl)-4,5-dihydro-1,2-oxazol-5-yl]methyl]piperidine-3-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C20H27FN2O5S
assistant