[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][N@@+1][Branch2][Ring2][Branch2][C][C][C@][C@@H1][C][=Branch1][C][=O][C][C][C@][Ring1][#Branch1][Branch2][Ring1][#Branch1][C@H1][Ring1][O][C][C][=C][Ring1][O][C][=Branch1][=Branch2][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][O][Ring1][S][O][C][C][C][C][Ring1][Ring1]"}, {"from": "gpt", "value": "The molecule is a pheriphally-acting \u03bc-opioid antagonist that acts on the gastrointestinal tract to decrease opioid-induced constipation without producing analgesic effects or withdrawal symptoms. It is also a weak CYP2D6 inhibitor. FDA approved in 2008."}]