## Endpoint to Predict
- Endpoint scope: assay
- Measurement type: IC50
- Label type: continuous
- Binary semantics: pchembl
- Assay description: Fluorescence Polarization Assay: Expression and purification of the BRD4(I) recognition domain: colonies of newly transformed plasmid DNA from E. coli BL21(DE3)-condon plus-RIL cells were cultivated in 50 mL of Terrific Broth medium containing 50 μg/mL kanamycin and 34 μg/mL chloramphenicol at 37° C. overnight (starting culture). The starting culture was then diluted 100-fold in 1 L of fresh TB medium and the cells were grown at 37° C. to an optical density of about 0.8 at and then the temperature was lowered to 16° C. When the system was equilibrated at 16° C., the optical density at was approximately 1.2, and protein expression was induced with 0.2 mmol of isopropyl-β-D-thiogalactopyranoside (IPTG) overnight at 16° C. Bacteria were harvested by centrifugation (4000×g, 20 minutes, 4° C.) and stored as a pellet at −80° C. The cells expressing His 6-tagged protein was resuspend in lysis buffer [50 mmol 4-hydroxyethylpiperazineethanesulfonic acid (HEPES), 25° C., pH 7.5, 500 mmol NaCl, 10 mmol imidazole, 5% glycerol and freshly added 0.5 mmol of tris(2-carboxyethyl)phosphine hydrochloride (TCEP) and 1 mmol of phenylmethanesulfonyl fluoride (PMSF)] and lysed at 4° C. using JN 3000PLUS high pressure homogenizer (JNBIO-Guangzhou, China). The lysate was clarified by centrifugation (12,000×g for 1 hour at 4° C.) and applied to a nickel-nitriloacetate agarose column. The column was washed once with 50 mL of wash buffer containing 30 mmol of imidazole. The protein was eluted using imidazole in an elution buffer in a stepwise elution (100-250 mmol imidazole in 50 mmol HEPES, 25° C., pH 7.5, 500 mmol NaCl, 5% glycerol). All fractions were collected and monitored by SDS-polyacrylamide gel electrophoresis (Bio-Rad Criterion TM Precast Gels, 4-12% Bis-Tris, 1 mm, from Bio-Rad, CA). After 1 mmol of dithiothreitol (DTT) was added, the eluted proteins were treated with tobacco plaque virus (TEV) protease overnight at 4° C. to remove the His6 tag. The protein was concentrated and further purified by size exclusion chromatography on a Superdex 75 16/60 HiLoad gel filtration column. The samples were monitored by SDS-polyacrylamide gel electrophoresis and concentrated to 8-10 mg/mL with gel filtration buffer, 10 mmol Hepes pH 7.5, 500 mM NaCl, 1 mmol DTT, and used for protein binding assays and crystallization.
- Target name: Bromodomain-containing protein 4
- Target type: SINGLE PROTEIN
- Target organism: Homo sapiens

## Reference Molecule A
- Canonical SMILES: Cc1ccc(-n2nc(C(=O)N3C[C@@H](C)N[C@@H](C)C3)nc2-c2ccc3c(c2)N(C2CC(F)(F)C2)C(C)C(=O)N3C)cc1
- Properties:
- ChEMBL ID: CHEMBL5849616
- Molecular weight: 563.65
- Heavy atoms: 41
- Hydrogen bond donors: 1
- Hydrogen bond acceptors: 6
- TPSA: 86.6
- LogP: 4.03
- Rotatable bonds: 4
- Ring count: 6
- Aromatic rings: 3
- Formal charge: 0
- Fraction Csp3: 0.47
- QED: 0.52

## Known Reference Result on This Endpoint
- Molecule A clean result: median pChEMBL = 7.7
- This result is provided as context for predicting Molecule B on the same endpoint.

## Reference Molecule A Other ChEMBL Evidence
- type IC50; relation =; value 20.1; units nM; pChEMBL 7.7; comment 1068950

## Query Molecule B
- Canonical SMILES: Cc1ccc(-n2nc(C(=O)N3CCN(C)CC3)nc2-c2ccc3c(c2)N(C2CC2)C(C)C(=O)N3C)cc1
- Properties:
- ChEMBL ID: CHEMBL4556261
- Molecule type: Unknown
- Molecular weight: 499.62
- Heavy atoms: 37
- Hydrogen bond donors: 0
- Hydrogen bond acceptors: 6
- TPSA: 77.81
- LogP: 2.96
- Rotatable bonds: 4
- Ring count: 6
- Aromatic rings: 3
- Formal charge: 0
- Fraction Csp3: 0.43
- QED: 0.55

## Molecule Similarity
- Weighted Tanimoto: 0.68

Answer: 7.8