YKL-5-124 TFA, a potent and selective irreversible covalent inhibitor of CDK7, demonstrates IC50 values of 53.5 nM for CDK7 and 9.7 nM for the CDK7/Mat1/CycH complex. It exhibits over 100-fold selectivity for CDK7 over CDK9 and CDK2, while showing no activity against CDK12 and CDK13. This compound effectively induces cell-cycle arrest, inhibits E2F-driven gene expression, and has minimal impact on the phosphorylation status of RNA polymerase II.

YKL-5-124, a potent, selective and covalent CDK7 inhibitor with an IC50 of 9.7 nM, 1300 nM and 3020 nM for CDK7/Mat1/CycH, CDK2 and CDK9 respectively, displays biochemical and cellular selectivity for CDK7 over CDK12/13.

YKL-5-124 TFA is a potent, selective, irreversible and covalent inhibitor of CDK7 (IC50s of 53.5 nM and 9.7 nM for CDK7 and CDK7/Mat1/CycH, respectively).

CDK7-IN-1 is an analog derived from YKL-5-124 and functions as an inhibitor of cyclin-dependent kinase 7 (cdk7). It exhibits strong inhibitory activity, with an IC50 value of less than 100 nM (WO 2016105528 A2, Compound 215).