Method for reversing multiple drug resistant phenotype

A method for reversing multiple drug resistance (MDR) phenotype in tumors insensitive to hydrophobic chemotherapeutic drugs due to over expression of mdr-1, comprising administering an effective amount of a long chain amino alcohol compound, wherein the long chain amino alcohol compound includes resolved enantiomers, resolved diastereomers, hydrates, salts, solvates or mixtures thereof from formula I or from formula II:

• formula I ##STR8## wherein n is an integer from one to four and m is an integer from four to twenty, R.sub.1 and R.sub.2 are independently hydrogen, a straight or branched chain alkyl, alkenyl or alkynyl of up to twenty carbon atoms in length or --(CH.sub.2).sub.w R.sub.5, wherein if R.sub.1 or R.sub.2 is --(CH.sub.2).sub.2 R.sub.5, w is an integer from one to twenty and R.sub.5 is an hydroxyl, halo, or C.sub.1-8 alkoxyl group, R.sub.1 and R.sub.2 jointly form a saturated or unsaturated heterocyclic having from four to eight carbon atoms, R.sub.3 is hydrogen or C.sub.1-3, wherein a total sum of carbon atoms comprising R.sub.1 and R.sub.2, (CH.sub.2).sub.n and (CH.sub.2).sub.m does not exceed forty, R.sub.4 is a heterocyclic moiety having from 4-7 atoms, including a nitrogen atom in one ring or two fused rings;
• or
• formula II ##STR9## wherein n, m, R.sub.3, and R.sub.4 are defined as provided in formula I, R.sub.6 and R.sub.7 are hydrogen, a straight or branched chain alkane, alkene or alkyne of up to twenty carbon atoms in length, or --(CH.sub.2).sub.x R.sub.8, at least one of R.sub.6 or R.sub.7 is --(CH.sub.2).sub.2 R.sub.8, x is an integer from zero to fourteen and R.sub.8 is a moiety having a general structure as provided in formula III ##STR10## wherein m, R.sub.3, and R.sub.4 are defined as provided in formula I, Z is N or Ch, p is an integer from zero to four, and R.sub.9 is H or a straight or branched chain alkane, alkene or alkyne of up to twenty carbon atoms in length.