This disclosure provides compounds with Bcl inhibitory activity based on a new chemical scaffold, as shown in Formula (I). The phospholidine compounds can include a P-phenyl phospholidine moiety which is substituted with an N-aryl or N-heteroaryl group. The P-phenyl phospholidine moiety can be optionally substituted at phosphorus with thio (═S) instead of oxo (═O). A second heteroatom attached to phosphorus can be cyclically linked to the N-substituted nitrogen atom of the phospholidine that is 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.