Tariquidar Analogues: Synthesis by CuI‐Catalysed N/O–Aryl Coupling and Inhibitory Activity against the ABCB1 Transporter

Less lipophilic and better water soluble tariquidar analogues were synthesised from one central anthranilic acid derived building block by CuI‐catalysed N/O–arylation reactions. The compounds were tested for their inhibitory activity against the ABCB1 transporter in a flow cytometric calcein‐AM efflux assay. A correlation between their calculated log P values and their activities was observed, with the more lipophilic analogues being as potent as the reference substance tariquidar.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)