CHEMBL5735504

Inhibition of Lysine Gingipain: The capacities of compounds of the present invention to inhibit the activity of lysine gingipain were measured in a fluorogenic assay similar to those described by Barret (Biochemical Journal. 1980, 187(3), 909). The specific assay conditions were as follows. Buffer: pH=7.5, 100 mM Tris-HCl, 75 mM NaCl, 2.5 mM CaCl2), 10 mM cysteine, 1% DMSO after all additions. Protein: 0.1 nM Kgp, isolated from culture of Porphyromonas gingivalis, as described by Pike et al. (J. Biol. Chem. 1994, 269(1), 406), and Potempa and Nguyen (Current Protocols in Protein Science. 2007, 21.20.1-21.20.27). Fluorogenic substrate: 10 μM Z-His-Glu-Lys-MCA. Time=90 minutes. Temperature=37° C. Each compound: 10 concentrations, starting at either 100 μM or 100 nM, with lower concentrations generated by serial 3-fold dilutions. By testing a range of concentrations for each compound, the concentration required to inhibit the activity of lysine gingipain by 50% (the “IC50”) was determined. Under the described assay conditions, the signal-to-noise ratio was excellent, and the Z factor was greater than 0.6. Compounds in Table 1 were tested, as well as the compounds set forth in Table 2 below.The capacities of compounds of the present invention to inhibit the activity of cathepsins B, H, K, L, and S were measured in similar assays. Boc-Leu-Arg-Arg-AMC (20 μM) in sodium acetate buffer (50 mM, pH 5.5) containing DTT (1 mM) and EDTA (2 mM) was used for the Cathepsin B assay. L-Arg-AMC (20 μM) in sodium acetate buffer (50 mM, pH 5.5) containing DTT (1 mM) and EDTA (2 mM) was used for the Cathepsin H assay. Z-Phe-Arg-AMC (10 μM) in HEPES buffer (50 mM, pH 7.4) containing DTT (2.5 mM) and EDTA (1 mM) was used for the Cathepsin K assay. Z-Phe-Arg-AMC (20 μM) in sodium acetate buffer (50 mM, pH 5.5) containing DTT (1 mM) and EDTA (2 mM) was used for the Cathepsin L assay. Z-Leu-Arg-AMC (10 μM) in sodium acetate buffer (25 mM, pH 4.5) containing DTT (2.5 mM) and NaCl (50 mM) was used for the Cathepsin S assay.