| abstract |
Use of a compound of formula 1 or a pharmaceutically acceptable salt thereof in the manufacture of a medicament as a major chemotherapeutic agent to induce cell death in neoplastic cells or to enhance the efficacy of chemotherapy for treating multidrug resistant neoplastic cells.n n n Formula 1n n n n n n n n Wheren n n R 1 is hydroxyl, C 1-4 alkoxyl, C 1-4 alkylcarbonyloxymethoxyl, phenyl C 1-2 alkylamino group, 2,5-pyrrolidinedione-1- (C 1-4 ) Alkoxy or Wherein X 1 is a chemical bond or C 1-2 alkylene, X 2 is hydrogen, or when X 1 is methylene, it is a carboxyl which forms a 5-membered ring with X 1, and X 3 is hydrogen or C 1 -2 alkyl, X 4 is hydrogen or C 1-2 alkyl, or X 3 and X 4 together form a 5-membered ring, and at least one of X 2 , X 3 and X 4 is hydrogen),n n n R 2 is C 3-4 alkyl,n n n R 3 is C 1-4 alkyl, , , . or (Where n is an integer of 0 to 3). |