Exploration of bromodomain ligand-linker conjugation sites for efficient CBP/p300 heterobifunctional degrader activity

Bioorg Med Chem Lett. 2024 Feb 24:129676. doi: 10.1016/j.bmcl.2024.129676. Online ahead of print.ABSTRACTSynthesis of proteolysis targeting chimeras (PROTACs) involves conjugation of an E3 ligase binding ligand to a ligand targeting a protein of interest via a rigid or flexible chemical linker. The choice of linker conjugation site on these ligands can be informed by structural analysis of ligand-target binding modes, the feasibility of synthetic procedures to access specific sites, and computational modeling of predicted ternary complex formations. Small molecules that target bromodomains - epigenetic readers of lysine acetylation - typically offer several potential options for linker conjugation sites. Here we describe how varying the linker attachment site (exit vector) on a CBP/p300 bromodomain ligand along with linker length affects PROTAC degradation activity and ternary complex formation. Using kinetic live cell assays of endogenous CBP and p300 protein abundance and bead-based proximity assays for ternary complexes, we describe the structure-activity relationships of a diverse library of CBP/p300 degraders (dCBPs).PMID:38408512 | DOI:10.1016/j.bmcl.2024.129676
Source: Bioorganic and Medicinal Chemistry Letters - Category: Chemistry Authors: Source Type: research