This disclosure provides compounds with Bcl inhibitory activity based on a new chemical scaffold. Acyl phosphonamidate compounds may include a P-phenyl phosphonamidate moiety which is N-acylated with an aroyl or heteroaroyl group. The P-phenyl phosphonamidate moiety can be optionally substituted at phosphorus with thio (═S) instead of oxo (═O), and/or with a thioxy group or a second amino group instead of an oxy group. One of the heteroatoms attached to phosphorus can be cyclically linked to a carbon atom of the adjacent phenyl ring attached to the phosphorus to provide, together with the phosphorus atom through which they are connected, a heterocyclic ring. By incorporating such a cyclic constraint between two phosphorus substituents of the core linking moiety a favorable binding conformation can be promoted in the compounds. Selected compounds promote apoptosis in senescent cells, and can be developed for treating senescent-related conditions, such as osteoarthritis, ophthalmic disease, pulmonary disease, and atherosclerosis. Selected compounds promote apoptosis in cancer cells, and can be developed as chemotherapeutic agents.