[{"from": "human", "value": "Provide a brief overview of this molecule. [C][O][C][=Branch1][C][=O][O][C][C][=C][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][N+1][=Branch1][C][=O][O-1]"}, {"from": "gpt", "value": "The molecule is a carbonate ester that is dimethyl carbonate in which one of the methyl groups has been replaced by a 4-nitrobenzyl group."}]