Patent ID: 6054437
Filing Date: 2000-04-25
Classification: A61K,A61P

Abstract:
A method for potentiating chemotherapy to treat multidrug-resistant neoplastic cells, comprising:administering a compound of formula I or a pharmaceutically acceptable salt thereof to a patient having said multidrug-resistant neoplastic cells, substantially contemporaneously with an effective amount of antineoplastic chemotherapy, in an amount sufficient to potentiate said chemotherapy, said multidrug-resistant neoplastic cells being sensitive to said compound or said salt in combination with said chemotherapy: ##STR47## where R.sup.1 is hydroxyl, C1-4 alkoxyl, C1-4 alkylcarbonyloxymethoxyl, phenyl C1-2 alkylamino group, 2,5-pyrrolidinedione-1-alkoxyl (C1-4), or ##STR48## wherein X.sup.1 is a chemical bond or C1-2 alkylene, X.sup.2 is hydrogen or carboxyl forming a 5-membered ring with X.sup.1 when X.sup.1 is methylene, X.sup.3 is hydrogen or C1-2 alkyl, X.sup.4 is hydrogen or C1-2 alkyl, or X.sup.3 and X.sup.4 together form a 5-membered ring, in which at least one of X.sup.2, X.sup.3, and X.sup.4 is hydrogen,R.sup.2 is C3-4 alkyl, R.sup.3 is C1-4 alkyl, ##STR49## in which n is an integer of 0 to 3.