You are a chemist. Please follow the instructions to convert the structure to the corresponding name.
system
Please write the molecular formula of the molecule (2R)-2-[[(2R)-2-(9H-fluoren-9-ylmethoxycarbonylamino)butanoyl]amino]-3-(1H-imidazol-5-yl)propanoic acid .
user
C25H26N4O5
assistant