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.