[{"from": "human", "value": "Could you provide a description of this molecule? [C][=C][C][=Branch2][Ring1][C][=C][Branch1][#Branch2][C][=C][Ring1][=Branch1][N+1][=Branch1][C][=O][O-1][N+1][=Branch1][C][=O][O-1][F]"}, {"from": "gpt", "value": "The molecule is an aromatic hydrocarbon composed of a benzene ring linked to two nitro groups and one fluoride group that is used for N-terminal amino acid sequencing by the Sanger method. In vitro, dinitrofluorobenzene (DNFB) reacts with the amine group in amino acids to produce dinitrophenyl (DNP)-amino acids. Then the sample is subjected to acid hydrolysis. Under these conditions, the peptide bonds are broken but the DNP-amino acid bonds remain intact. The DNP-amino acids can be recovered and their identities can be determined through the use of various chromatography techniques. This reagent can also be used to distinguish the reduced and oxidized forms of glutathione and cysteine."}]