Abstract: The invention relates generally to small molecules that mimic the biological activity of certain peptides and proteins, to compositions containing them and to their use. In particular, the invention relates to compounds of the general formula (I) that mimic the biological activity of BH3-only proteins and are capable of binding to and neutralizing pro-survival Bcl-2 proteins: wherein A1, A2, B1, B2, B3, X, Z, R1, R2, R3 and t are as described herein. The invention also relates to processes of preparing the benzenesulfonamide compounds that mimic portions of peptides and proteins, and to the use of such compounds in the regulation of cell death and the treatment and/or prophylaxis of diseases or conditions associated with the deregulation of cell death.