Development of Human Carbonic Anhydrase II Heterobifunctional Degraders.
O'Herin, C.B., Moriuchi, Y.W., Bemis, T.A., Kohlbrand, A.J., Burkart, M.D., Cohen, S.M.(2023) J Med Chem 
- PubMed: 36735827 
- DOI: https://doi.org/10.1021/acs.jmedchem.2c01843
- Primary Citation of Related Structures:  
8EMU, 8EXC, 8EXG, 8EYL - PubMed Abstract: 
Human carbonic anhydrase II (hCAII) is a metalloenzyme essential to critical physiological processes in the body. hCA inhibitors are used clinically for the treatment of indications ranging from glaucoma to epilepsy. Targeted protein degraders have emerged as a promising means of inducing the degradation of disease-implicated proteins by using the endogenous quality control mechanisms of a cell. Here, a series of heterobifunctional degrader candidates targeting hCAII were developed from a simple aryl sulfonamide fragment. Degrader candidates were functionalized to produce either cereblon E3 ubiquitin ligase (CRBN) recruiting proteolysis targeting chimeras (PROTACs) or adamantyl-based hydrophobic tags (HyTs). Screens in HEK293 cells identified two PROTAC small-molecule degraders of hCA. Optimization of linker length and composition yielded a degrader with sub-nanomolar potency and sustained depletion of hCAII over prolonged treatments. Mechanistic studies suggest that this optimized degrader depletes hCAII through the same mechanism as previously reported CRBN-recruiting heterobifunctional degraders.
Organizational Affiliation: 
Department of Chemistry and Biochemistry, University of California, La Jolla, California 92093, United States.