You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl (3S)-3-[[(1R)-1-(2-ethenyl-3-ethylphenyl)ethyl]-[(2-methylpropan-2-yl)oxycarbonyl]amino]pyrrolidine-1-carboxylate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C26H40N2O4
assistant