A series of acylpyrogallols were designed, synthesized, and evaluated as small-molecule inhibitors of antiapoptotic Bcl-2 proteins. The most potent compound 9 (TM-179) binds to Bcl-2 with an IC50 of 170 nM and to Mcl-1 with a Ki of 37 nM. Compound 9 potently inhibits cell growth and induces apoptosis in human breast and prostate cancer cell lines.