You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
tert-butyl N-[(8R)-8-[2-fluoro-5-[(Z)-2-fluoro-2-(5-isocyanopyridin-2-yl)ethenyl]phenyl]-5,8-dimethyl-4,4-dioxo-4lambda6-thia-5,7-diazaspiro[2.5]oct-6-en-6-yl]-N-[(2-methylpropan-2-yl)oxycarbonyl]carbamate is the IUPAC name of a molecule. Please give its molecular formula.
user
C31H35F2N5O6S
assistant