## Endpoint to Predict
- Endpoint scope: assay
- Measurement type: IC50
- Label type: continuous
- Binary semantics: pchembl
- Assay description: 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, 21.2.1-21.2.27). 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.
- Assay organism: Homo sapiens
- Target name: Procathepsin L
- Target type: SINGLE PROTEIN
- Target organism: Homo sapiens

## Reference Molecule A
- Canonical SMILES: NCCCCC(NC(=O)C1CCCC1)C(=O)COc1cccc(F)c1
- Properties:
- ChEMBL ID: CHEMBL5771146
- Molecular weight: 350.43
- Heavy atoms: 25
- Hydrogen bond donors: 2
- Hydrogen bond acceptors: 4
- TPSA: 81.42
- LogP: 2.58
- Rotatable bonds: 10
- Ring count: 2
- Aromatic rings: 1
- Formal charge: 0
- Fraction Csp3: 0.58
- QED: 0.64

## Known Reference Result on This Endpoint
- Molecule A clean result: median pChEMBL = 5.26
- This result is provided as context for predicting Molecule B on the same endpoint.

## Reference Molecule A Other ChEMBL Evidence
- type IC50; relation =; value 5526; units nM; pChEMBL 5.26; comment 932172

## Query Molecule B
- Canonical SMILES: NCCCCC(NC(=O)c1ccc(F)nc1)C(=O)COc1ccon1
- Properties:
- ChEMBL ID: CHEMBL5764494
- Molecular weight: 350.35
- Heavy atoms: 25
- Hydrogen bond donors: 2
- Hydrogen bond acceptors: 7
- TPSA: 120.34
- LogP: 1.08
- Rotatable bonds: 10
- Ring count: 2
- Aromatic rings: 2
- Formal charge: 0
- Fraction Csp3: 0.38
- QED: 0.49

## Molecule Similarity
- Weighted Tanimoto: 0.39

Answer: 5.2