[{"from": "human", "value": "Please give me some details about this molecule. [C][C][C][=Branch1][C][=O][N][Branch2][Ring1][Ring2][C][C][C][N][Branch1][Branch1][C][C][Ring1][=Branch1][C][C][=C][C][=C][C][=C][Ring1][=Branch1][C][=C][C][=C][C][=C][Ring1][=Branch1]"}, {"from": "gpt", "value": "The molecule is a fentanyl analog opioid that was on the list of Schedule I drugs in America in 1985 due to its structural similarity to fentanyl. In 2010 it was removed from the list after it was found to have minimal opioid activity. Benzylfentanyl has a Ki of 213nM at the mu opioid receptor, binding around 200x less strongly than fentanyl itself."}]