has role 2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile dexverapamil (2R)-(+)-2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile (+)-verapamil (+)-(R)-5-((3,4-dimethoxyphenethyl)methylamino)-2-(3,4-dimethoxyphenyl)-2-isopropylvaleronitrile chebi_ontology CHEBI:77734 (+)-(R)-verapamil (+)-(2R)-2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile (+)-2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile (R)-(+)-verapamil (+)-3-(3,4-dimethoxyphenyl)-6-((5,6-dimethoxyphenethyl)methylamino)hexane-3-carbonitrile A 2-(3,4-dimethoxyphenyl)-5-{[2-(3,4-dimethoxyphenyl)ethyl](methyl)amino}-2-(propan-2-yl)pentanenitrile that has <i>R</i> configuration. It competitively inhibits the multidrug resistance efflux pump P-glycoprotein (MDR-1, EC 3.6.3.44), thereby potentially increasing the effectiveness of a wide range of antineoplastic drugs which are inactivated by MDR-1 mechanisms. Dexverapamil exhibits lower calcium antagonistic activity and toxicity than racemic verapamil. (R)-verapamil (S)-verapamil dexverapamil(1+) EC 3.6.3.44 (xenobiotic-transporting ATPase) inhibitor