Disclosed is method for treating cancer in a mammal, comprising administering to a mammal in need thereof a compound of the formula: wherein R1, R2, and R3 are as defined herein, wherein the cancer is an autophagy-dependent cancer, in an amount sufficient to induce autophagy in the cell and cause the death of cancer cells. Also disclosed is a method for selectively killing cancer cells in a patient afflicted with cancer, comprising administering to the mammal, wherein the cancer cells are autophagy-dependent cancer cells, in an amount sufficient to induce autophagy in the cells and cause the death of the cancer cells.