[{"from": "human", "value": "Provide a brief overview of this molecule. [C][C][N+1][Branch2][Ring2][C][C][C][C][Ring1][=Branch1][Branch1][Branch1][C][C][Ring1][=Branch1][C][Branch1][=Branch2][C][=C][C][=C][C][=C][Ring1][=Branch1][Branch1][=Branch2][C][=C][C][=C][C][=C][Ring1][=Branch1][O][C][C][O][C][C][=C][C][=C][C][=C][Ring1][=Branch1].[Br-1]"}, {"from": "gpt", "value": "The molecule is the bromide salt form of umeclidinium, a muscarinic receptor antagonist, with bronchodilator activity. Although it does not display selectivity for specific muscarinic receptors, on topical application, umeclidinium acts mainly on M3 muscarinic receptors located on smooth muscle cells, thereby preventing smooth muscle contraction and resulting in bronchodilatory effect."}]