You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
9H-fluoren-9-ylmethyl N-[(2S)-1-[methyl-(4-nitrophenyl)sulfonylamino]-1-oxopropan-2-yl]carbamate The above is the IUPAC name of a molecule. Write its molecular formula.
user
C25H23N3O7S
assistant