Arylmethyloxyphenyl derivatives: small molecules displaying P-glycoprotein inhibition

Some arylmethyloxyphenyl derivatives were prepared as simplified structures of analogous arylpiperazines with high affinity toward dopaminergic D(2) and serotonergic 5-HT(1A) receptors and inhibiting P-glycoprotein (P-gp). The compounds 5b and 8b displayed good P-gp inhibition activity measured as [(3)H]vinblastine transport inhibition in the Caco-2 cell monolayer and intracellular doxorubicin accumulation in MCF7/Adr cells by flow cytometry. Compounds 5b and 8b also inhibited, dose-dependently, ATP-ase activation induced by P-gp substrate vinblastine.