Donated Chemical Probes

Target	BRD2 BRD3 BRD4 BRDT
Targeted domain	BD2
Mode of action	Inhibitor
Control
Recommended cellular usage concentration	≤ 10 µM
In vivo use	Yes
Synonyms	Compound 20
Donated by	GlaxoSmithKline

Inhibitor/agonist potency: goal is < 50 nM (IC₅₀, K_D)	Surpasses criterion: :BET mutant TR-FRET assay: BRD2 (BD1) pIC₅₀ = 4.6 (n = 13); (BD2) 6.5 (n= 20); 80-fold BRD3 (BD1) pIC₅₀ = 4.6 (n = 6); (BD2) 7.1 (n = 16); 320-fold BRD4 (BD1) pIC₅₀ = 4.8 (n = 14); (BD2) 7.1 (n = 16); 200-fold BRDT (BD1) pIC₅₀ = 4.6 (n = 9); (BD2) 6.7 (n = 18); 125-fold BROMOScan (DiscoverX): BRD2 (BD1): pK_d =4.9; (BD2) 7.8; 800-fold BRD3 (BD1): pK_d= 5.1; (BD2) 7.9 ; 630-fold BRD4 (BD1): pK_d =5.6; (BD2)8.2; 400-fold BRDT (BD1): pK_d = 5.3; (BD2) 7.8; 320-fold SPR BRD4 (BD1): pK_d = 5.0; BRD4 (BD2) pK_d = 7.3 (200-fold)
Selectivity within target family: > 30-fold	Surpasses criterion:: BROMOScan (DiscoverX) (34 tested): selective for the BD2 domain of BET proteins; closest hits: TAF1 BD2 (pKd = 5.4), EP300 (pKd = 5.1) and CREBBP (pKd = 5.0)
Selectivity outside target family	Selectivity screen (48 targets tested): clean; Clean PDSP scan
On target cell activity for cell-based targets: goal is < 1 µM IC₅₀/EC₅₀	Surpasses criterion: Lipopolysaccharide (LPS)-stimulated human whole blood assay: MCP-1 (pIC₅₀ = 6.1± 0.2 (n=8)) LPS-PBMC assay (MCP-1) pIC₅₀ = 7.2 ± 0.3 (n = 8)