Drug resistance is one of the major problems in cancer chemotherapy. Search for thedrugs that can reverse the resistance, especially the multidrug resistance (MDR) is a taskfor improving the therapeutic result of cancer chemotherapy. MDR appears to a largeextent to be due to the overexpression of a membrane-associated P-glycoprotein (P-gp)which pumps anticancer drugs out of MDR cells, thereby preventing accumulation of drugs Mdr appears to a large extent to be due to the overexpression. Drug resistance is one of the major problems in cancer chemotherapy. Search for thedrugs that can reverse the resistance, especially the multidrug resistance (MDR) is a taskfor improving the therapeutic result of cancer chemotherapy. Of a membrane-associated P-glycoprotein (P-gp)which pumps anticancer drugs out of MDR cells, now preventing accumulation of drugs