[{"from": "human", "value": "From the provided chemical reaction, propose some possible reagents that could have been used. [O][=C][Branch1][C][O][C][C][C][C][C][C][C][C][C][C][Br].[O][=S][Branch1][C][Cl][Cl]>>[O][=C][Branch1][C][Cl][C][C][C][C][C][C][C][C][C][C][Br]"}, {"from": "gpt", "value": "[C][N][Branch1][C][C][C][=O].[Cl][C][Cl]"}]