[{"from": "human", "value": "Could you provide a description of this molecule? [C][C][Branch1][C][C][C@@][Branch2][Ring1][#Branch2][C][C][C][N][Branch1][C][C][C][C][C][=C][C][=Branch1][#Branch2][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][C][O][C][Branch1][Ring1][C][#N][C][=C][C][=Branch1][#Branch2][=C][Branch1][Branch1][C][=C][Ring1][=Branch1][O][C][O][C].[Cl]"}, {"from": "gpt", "value": "The molecule is the R-enantiomer of the calcium channel blocker verapamil. Dexverapamil competitively inhibits the multidrug resistance efflux pump P-glycoprotein (MDR-1), thereby potentially increasing the effectiveness of a wide range of antineoplastic drugs which are inactivated by MDR-1 mechanisms.  This agent exhibits decreased calcium antagonistic activity and toxicity compared to racemic verapamil. (NCI04)"}]