1-Benzyl-1,2,3,4-tetrahydroisoquinoline Derivatives and Optically Pure Isomers as Novel Promising Multidrug Resistance (MDR) Reversing Agents

A series of chiral compounds were designed and synthesized as novel multidrug resistance (MDR) modulators on the basis of tetrahydroisoquinolines to reverse cancerous MDR on K562 cells and K562/DOX cells by using the MTT assay. The treatment of K562/DOX cells with 9e, 10a and 10e led to increased intracellular accumulation and decreased efflux of doxorubicin. The pharmacological effects of these tetrahydroisoquinolines on P-glycoprotein (P-gp) mediated MDR were much stronger than that of positive control drug verapamil.