A method of inhibiting the growth of leukemic hematopoietic stem cells in a subject with leukemia is described. The method includes administering a therapeutically effective amount of a composition including a compound of formula I: I wherein R1 is independently selected from hydrogen and methyl R2 is selected from the group consisting of 4,8-dimethyl-non-1-enyl, 4,8-dimethyl-nonyl, non-1-enyl, and nonanyl groups X is a carboxyl, phosphonic, or sulfonic moiety, and n is an integer from 1 to 6, or a compound of Formula II: II wherein R1 is a C6-C12 alkyl or C6-C12 alkoxy group R2 is independently selected from the group consisting of hydrogen, methoxy, and hydroxyl and R3 is an alkyl or cycloalkyl group or a pharmaceutically acceptable salt thereof.