GSK973 is a highly selective and orally bioavailable inhibitor that targets the second bromodomains (BD2s) of the BET family. It exhibits a pIC 50 of 7.8 and a pK d of 8.7 specifically for BRD4 BD2. Additionally, GSK973 demonstrates a remarkable selectivity of 1600-fold for BRD4 BD2 over BRD4 BD1. Moreover, it displays good potency against BRD2 BD2, BRD3 BD2, and BRDT BD2, with pIC 50 ranging from 7.4 to 7.8 and pK d ranging from 8.3 to 8.5.
BET bromodomain inhibitor 1 is an orally active, selective inhibitor of bromodomain and extra-terminal (BET) proteins. It specifically inhibits BRD4 with an IC50 of 2.6 nM. Additionally, BET bromodomain inhibitor 1 demonstrates high affinities towards BRD2(2), BRD3(2), BRD4(1), BRD4(2), and BRDT(2) with Kd values of 1.3 nM, 1.0 nM, 3.0 nM, 1.6 nM, and 2.1 nM, respectively. This compound exhibits anti-cancer activity.