3′-O, 4′-O-aromatic acyl substituted 7,8-pyranocoumarins: a new class of P-glycoprotein modulators

P-glycoprotein (Pgp) overexpression in tumour cells leads to multidrug resistance (MDR) and causes failure in cancer chemotherapy. We have previously identified (±)-praeruptorin A (PA) as a potential lead compound for Pgp modulators. In this study we investigated the MDR-reversing activities of PA derivatives.Series 7,8-pyranocoumarins with various C-3' and C-4' side chains had been semi-synthesized and their MDR-reversing activity was...