Skp2 inhibitor 2 (14f) impedes the F-box protein S-phase kinase-associated protein 2 (Skp2), demonstrating an IC50 of 10.2 μM against Skp2-Cks1. This compound targets Skp2, a component of cullin-RING ligases that recruits and ubiquitinates substrates, playing roles in both proteolytic and non-proteolytic processes [1].