[{"from": "human", "value": "What can you tell me about this molecule? [C][C][=C][C][=C][C][=C][Ring1][=Branch1][S][=Branch1][C][=O][=Branch1][C][=O][N][C][=Branch1][C][=O][C][=C][C][=Branch2][Ring2][=Branch2][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][C][C][=C][N][Branch2][Ring1][#Branch2][C][=C][Ring1][Branch1][C][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][N][C][=Branch1][C][=O][O][C][C][C][C][C][Ring1][Branch1][C][O][C]"}, {"from": "gpt", "value": "The molecule is an oral leukotriene receptor antagonist (LTRA) for the maintenance treatment of asthma, often used in conjunction with an inhaled steroid and/or long-acting bronchodilator. It is available as a tablet and is usually dosed twice daily. Another leukotriene receptor antagonist is montelukast (Singulair), which is usually taken just once daily.  Zafirlukast blocks the action of the cysteinyl leukotrienes on the CysLT1 receptors, thus reducing constriction of the airways, build-up of mucus in the lungs and inflammation of the breathing passages."}]