## Endpoint to Predict
- Endpoint scope: assay
- Measurement type: Kd
- Label type: continuous
- Binary semantics: pchembl
- Assay description: Bcl-2 Protein Family Binding Assay: Binding to Bcl-2 proteins Bcl-2, and Bcl-XL was assessed using the Bcl2scan platform: T7 phage strains displaying BCL2 proteins were grown in parallel in 24-well blocks in an E. coli host derived from the BL21 strain. E. coliwere grown to log-phase and infected with T7 phage from a frozen stock (multiplicity of infection=0.4) and incubated with shaking at 32° C. until lysis (90-150 minutes). The lysates were centrifuged (5,000×g) and filtered (0.2 μm) to remove cell debris. Streptavidin-coated magnetic beads were treated with biotinylated BIM peptide ligand for 30 minutes at room temperature to generate affinity resins for BCL2 assays. The liganded beads were blocked with excess biotin and washed with blocking buffer (SeaBlock (Pierce), 1% BSA, 0.05% Tween 20, 1 mM DTT) to remove unbound ligand and to reduce non-specific phage binding. Binding reactions were assembled by combining BCL2 proteins, liganded affinity beads, and test compounds in 1× binding buffer (20% SeaBlock, 0.17×PBS, 0.05% Tween 20, 6 mM DTT). Test compounds were prepared as 100× stocks in 100% DMSO. Kds were determined using an 11-point 3-fold compound dilution series with one DMSO control point. All compounds for Kd measurements were distributed by acoustic transfer in 100% DMSO. The compounds were then diluted directly into the assays such that the final concentration of DMSO was 0.9%. All reactions performed in polypropylene 384-well plates. Each was a final volume of 0.02 ml. The assay plates were incubated at room temperature with shaking for 1 hour and the affinity beads were washed with wash buffer (lx PBS, 0.05% Tween 20). The beads were then re-suspended in elution buffer (lx PBS, 0.05% Tween 20, 2 μM non-biotinylated affinity ligand) and incubated at room temperature with shaking for 30 minutes.
- Target name: Apoptosis regulator Bcl-2
- Target type: SINGLE PROTEIN
- Target organism: Homo sapiens

## Reference Molecule A
- Canonical SMILES: CC1(C)CCC(C23CC(C)(C2)C3)=C(CN2CCN(c3ccc(C(=O)NS(=O)(=O)c4ccc(N[C@H](CCN5CCC(O)CC5)CSc5ccccc5)c(S(=O)(=O)C(F)(F)F)c4)cc3)CC2)C1
- Properties:
- ChEMBL ID: CHEMBL5805527
- Molecular weight: 958.25
- Heavy atoms: 65
- Hydrogen bond donors: 3
- Hydrogen bond acceptors: 11
- TPSA: 139.36
- LogP: 8.34
- Rotatable bonds: 16
- Ring count: 9
- Aromatic rings: 3
- Formal charge: 0
- Fraction Csp3: 0.56
- QED: 0.09

## Known Reference Result on This Endpoint
- Molecule A clean result: median pChEMBL = 7.26
- This result is provided as context for predicting Molecule B on the same endpoint.

## Reference Molecule A Other ChEMBL Evidence
- type Kd; relation =; value 55; units nM; pChEMBL 7.26; comment 1262043

## Query Molecule B
- Canonical SMILES: CC1(C)CCC(c2ccc(Cl)cc2)=C(CN2CCN(c3ccc(C(=O)NS(=O)(=O)c4ccc(N[C@H](CCN5CCOCC5)CSc5ccccc5)c(S(=O)(=O)C(F)(F)F)c4)cc3)CC2)C1
- Properties:
- ChEMBL ID: CHEMBL443684
- Preferred name: NAVITOCLAX
- Molecule type: Small molecule
- Max clinical phase: 3
- Molecular weight: 974.63
- Heavy atoms: 65
- Hydrogen bond donors: 2
- Hydrogen bond acceptors: 11
- TPSA: 128.36
- LogP: 8.83
- Rotatable bonds: 16
- Ring count: 7
- Aromatic rings: 4
- Formal charge: 0
- Fraction Csp3: 0.43
- QED: 0.1

## Molecule Similarity
- Weighted Tanimoto: 0.71

Answer: 7.26