CHEMBL3706324

JAK1 and TYK2 Inhibition Assay: To determine inhibition constants (Ki), compounds were diluted serially in DMSO and added to 50 uL kinase reactions containing 1.5 nM JAK1, 0.2 nM purified JAK2 or 1 nM purified TYK2 enzyme, 100 mM Hepes pH7.2, 0.015% Brij-35, 1.5 uM peptide substrate, 25 uM ATP, 10 mM MgCl2, 4 mM DTT at a final DMSO concentration of 2%. Reactions were incubated at 22° C. in 384-well polypropylene microtiter plates for 30 minutes and then stopped by addition of 25 uL of an EDTA containing solution (100 mM Hepes pH 7.2, 0.015% Brij-35, 150 mM EDTA), resulting in a final EDTA concentration of 50 mM. After termination of the kinase reaction, the proportion of phosphorylated product was determined as a fraction of total peptide substrate using the Caliper LabChip 3000 according to the manufacturer's specifications. Ki values were then determined using the Morrison tight binding model (Morrison, J. F., Biochim. Biophys. Acta. 185:269-296 (1969).