[{"from": "human", "value": "Provide a brief overview of this molecule. [C][=C][C][=C][Branch1][=Branch2][C][=Branch1][Ring2][=C][Ring1][=Branch1][N+1][#N][N+1][=Branch1][C][=O][O-1]"}, {"from": "gpt", "value": "The molecule is the aromatic diazonium ion formed from diazotisation of the amino group in 2-nitroaniline. It has a role as a hapten."}]