Prenylated xanthones as potential P-glycoprotein modulators

Dimethylallyl (DMA) derivatives of a naturally occurring xanthone (decussat in 1) were prepared. Their activity as potential P-glycoprotein inhibitors was monitored by affinity of direct binding and compared to that of corresp onding DMA-flavones. Both classes of compounds exhibited the same structure -activity relationships. Decreasing polarity enhanced the binding affinity for the P-glycoprotein C-terminal cytosolic domain since DMA derivatives we re more active, bur, unsubstituted hydroxyl group close to the carbonyl was required for efficient activity. (C) 2000 Elsevier Science Ltd. All rights reserved.