CHEMBL5737799

SRC Inhibitory Activity Measurement: Regarding the conditions for measurement of in vitro inhibitory activity of compounds against SRC kinase activity, the price list of LabChip-series consumable reagents of PerkinElmer shows that FL-Peptide 4 corresponds to the substrate peptide for reaction to measure SRC kinase activity. Thus, FL-Peptide 4 was used as a substrate. The purified recombinant human SRC protein used in the test was purchased from Carna Biosciences, Inc.To measure the inhibitory activity, first, the compounds of the present invention were individually diluted with dimethyl sulfoxide (DMSO) stepwise. Subsequently, SRC protein, FL-Peptide 4 (final concentration: 1.5 μM), magnesium chloride (final concentration: 10 mM), ATP (final concentration: 15 μM), and a solution of the compound of the present invention in DMSO (final concentration of DMSO: 5%) were added to a reaction buffer (100 mM HEPES, pH of 7.0, 1 mM dithiothreitol, 0.003% Brij35, 0.04% Tween-20) containing a phosphatase inhibitor cocktail (PhosSTOP, Roche) and a protease inhibitor cocktail (complete Mini, EDTA-free, Roche) at recommended concentrations. Each mixture was incubated at 30° C. for 90 minutes to perform kinase reaction. EDTA diluted with a separation buffer available from PerkinElmer (final concentration: 30 mM) was then added thereto to terminate the kinase reaction. Finally, non-phosphorylated substrate peptides (S) and phosphorylated peptides (P) were separated and detected by microchannel capillary electrophoresis using LabChip EZ Reader II (PerkinElmer). The phosphorylation level was calculated from the height of the peaks of S and P, and the compound concentration at which phosphorylation was inhibited by 50% was defined as IC50 value (nM).