PROTAC CDK9 Degrader-1 is a CRBN-recruiting PROTAC selectively targeting on CDK9, consist of a CDK9 ligand (aminopyrazole analog) linked to a CRBN E3 ligand thalidomide.

PROTAC CDK9 degrader-2 (compounds 11c) is a potent and selective CDK9 degrader based on PROTAC, with an IC50 of 17 μM in MCF-7 cell lines. Natural product Wogonin binds ubiquitin E3 ligase cereblon (CRBN) via a linker to form PROTAC.