Compound (SMILES): CC(=O)Nc1cn2nc(-c3cncc(C(=O)NCCC(C)c4ccccc4)c3)ccc2n1
InChIKey: RBHTVXVLVZUGFC-UHFFFAOYSA-N
Target: Receptor-interacting serine/threonine-protein kinase 1 (SINGLE PROTEIN), Homo sapiens
UniProt: Q13546
Assay: RIPK1 HTRF Binding Assay: A solution was prepared containing 0.2 nM Anti GST-Tb (Cisbio, 61GSTTLB), 90.6 nM probe and 1 nM His-GST-TVMV-hRIPK1(1-324) in FRET Buffer (20 mM HEPES, 10 mM MgCl2, 0.015% Brij-35, 4 mM DTT, 0.05 mg/mL BSA). Using Formulatrix Tempest, the detection antibody/enzyme/probe solution (2 mL) was dispensed into wells of a 1536 plate (Black Low Binding Polystyrene 1536 Plate (Corning, 3724)) containing 10 nL of compounds of interest at appropriate concentration in DMSO. The plate was incubated at rt for 1 h. FRET was measured using the EnVision plate reader (Excitation: 340 nM, Emission: 520 nM/495 nM). Total signal (0% inhibition) was calculated from wells containing 10 nL DMSO only. Blank signal (100% inhibition) calculated from wells containing 10 nL of 15 nM staurosporine and internal controls.Cloning and Baculovirus Expression of RIPK1 ConstructThe coding region of human RIPK1(1-324) flanked by NdeI site at 5′ end and stop codon TGA and XhoI site at 3′ end was codon optimized and gene synthesized at GenScript USA Inc. (Piscataway, N.J.) and subcloned into a modified pFastBacl vector (Invitrogen, Carlsbad, Calif.) with N-terminal His-GST-TVMV tag, to generate His-GST-TVMV-hRIPK1(1-324)-pFB. The fidelity of the synthetic fragment was confirmed by sequencing.Baculovirus was generated for the construct using the Bac-to-Bac baculovirus expression system (Invitrogen) according to the manufacturer's protocol. Briefly, recombinant bacmid was isolated from transformed DH10Bac E. coli competent cells (Invitrogen) and used to transfect Spodoptera frugiperda (Sf9) insect cells (Invitrogen). Baculovirus was harvested 72 hours post transfection and a virus stock was prepared by infecting fresh Sf9 cells at a 1/1000 (v/v) ratio for 66 hours.For large scale protein production, Sf9 cells (Expression System, Davis, Calif.) grown in ESF921 insect medium (Expression System) at 2×106 cells/ml were infected with virus stock at a 1/100 (v/v) ratio for 66 hours. The production was carried out either at a 10 L scale in a 22 L cellbag (GE Healthcare Bioscience, Pittsburgh, Pa.) or at a 20 L scale in a 50 L cellbag using WAVE-Bioreactor System 20/50 (GE Healthcare Bioscience). The infected cells were harvested by centrifugation at 2000 rpm for 20 min at 4° C. in a SORVALL® RC12BP centrifuge. The cell pellets was stored at −70° C. before protein was purified.Purification of His-GST-TVMV-hRIPK1(1-324)RIPK1 containing cell paste was resuspended in 50 mM Tris pH 7.5, 150 mM NaCl, 10 mM imidazole, 5% glycerol, 5 mM MgSO4, 1 mM TCEP, 25 U/ml Benzonase, and Complete Protease Inhibitor tablets (1/50 ml, Roche Diagnostics, Indianapolis, Ind.). The cells were lysed by nitrogen cavitation using an unstirred pressure vessel @ 525 PSI (Parr Instrument Company, Moline, Ill.). The suspension was clarified by centrifugation at 136,000×g for 40 min, at 4° C. The lysate was decanted from the pellet and passed through a 5 ml NiNTA Superflow cartridge (Qiagen, Valencia, Calif.) using an AKTA Pure (GE Healthcare). Column was eluted with 10 CV linear gradient into 50 mM Tris 7.5, 150 mM NaCl, 500 mM imidazole, 5% glycerol, 1 mM TCEP. Peak fractions were pooled and loaded directly onto 5 ml GSTrap 4B column (GE Healthcare). Column was washed with 50 mM Tris 7.0, 150 mM NaCl, 5% glycerol, 1 mM DTT and eluted in 10 CV linear gradient into 50 mM Tris 8.0, 150 mM NaCl, 20 mM reduced glutathione, 5% glycerol, 1 mM DTT. Fractions identified by SDS-PAGE as containing RIPK1 were pooled and concentrated using 30 kDa MWCO spin concentrators (Amicon Ultra-15, Millipore, Billerica, Mass.) and loaded onto a HiLoad 26/600 Superdex 200 column (GE Healthcare) equilibrated in 25 mM Tris 7.5, 150 mM NaCl, 2 mM TCEP, 5% glycerol. The RIPK1 protein eluted as a dimer off the SEC column.The yield was 8 mg/L with a purity >95% as determined by Coomassie staind SDS-PAGE gel analysis.
Measurement: IC50 = 41 nM (pChEMBL 7.389999866485596)
Descriptors: MW 428.5, ALogP 3.67, HBA 6, HBD 2, PSA 101.28, QED 0.47