## Endpoint to Predict
- Endpoint scope: assay
- Measurement type: Ki
- Label type: continuous
- Binary semantics: pchembl
- Assay description: Adenosine Receptor Binding Assay: Binding affinity of test compounds to four human adenosine receptors, A1, A2A, A2B and A3 was determined in radioligand competitive binding assay (conducted by Cerep, France) using following protocols. For A1 receptor (A1R), membrane homogenates from CHO cells transfected with A1R were incubated for 60 min at 22° C. with 1 nM [3H]DPCPX in the absence or presence of the test compound in a buffer containing 50 mM Tris-HCl (pH 7.4), 5 mM MgCl2, 1 mM EDTA/Tris and 2 UI/mL ADA. For A2AR, membrane homogenates from HEK293 cells transfected with A2AR were incubated for 120 min at 22° C. with 6 nM [3H]CGS21680 in the absence or presence of the test compound in a buffer containing 50 mM Tris-HCl (pH 7.4), 10 mM MgCl2, and 2 UI/mL ADA. For A2B receptor (A2BR), membrane homogenates from HEK293 cells transfected with A2BR were incubated for 60 min at 22° C. with 5 nM [3H]CPX in the absence or presence of the test compound in a buffer containing 10 mM Hepes/Tris (pH 7), 1 mM MgCl2, and 1 mM EDTA. For A3 receptor (A3R), membrane homogenates from HEK293 cells transfected with A3R were incubated for 120 min at 22° C. with 0.15 nM [125I] AB-MECA in the absence or presence of the test compound in a buffer containing 50 mM Tris-HCl (pH 7.4), 5 mM MgCl2, 1 mM EDTA and 2 UI/mL ADA. Nonspecific binding was determined in the presence of unlabeled 1 μM DPCPX, 10 μM NECA, 100 μM NECA, and 1 μM IB-MECA in A1R, A2AR, A2BR, A3R binding assays, respectively. Following incubation, the samples are rapidly filtered and washed with ice-cold 50 mM Tris-HCl. Then filters are dried and counted for radioactivity in a scintillation counter (Topcount, Packard) using a scintillation cocktail (Microscint 0, Packard). Duplicate experiments were performed for each assay. The results are expressed as a percent inhibition of control radioligand specific binding.Mouse BBB Assay
- Assay organism: Homo sapiens
- Target name: Adenosine receptor A2a
- Target type: SINGLE PROTEIN
- Target organism: Homo sapiens

## Reference Molecule A
- Canonical SMILES: C[C@](C(=O)N[C@@H]1CCC[C@@H]1O)(c1ccccc1)n1ncc2c1nc(N)n1nc(-c3ccco3)nc21
- Properties:
- ChEMBL ID: CHEMBL5997347
- Molecular weight: 472.51
- Heavy atoms: 35
- Hydrogen bond donors: 3
- Hydrogen bond acceptors: 8
- TPSA: 149.39
- LogP: 2.11
- Rotatable bonds: 5
- Ring count: 6
- Aromatic rings: 5
- Formal charge: 0
- Fraction Csp3: 0.29
- QED: 0.35

## Known Reference Result on This Endpoint
- Molecule A clean result: median pChEMBL = 8.66
- This result is provided as context for predicting Molecule B on the same endpoint.

## Reference Molecule A Other ChEMBL Evidence
- type Ki; relation =; value 2.2; units nM; pChEMBL 8.66; comment 1217557

## Query Molecule B
- Canonical SMILES: CC1(O)CCC(NC(=O)[C@@](C)(c2ccccc2)n2ncc3c2nc(N)n2nc(-c4ccco4)nc32)CC1
- Properties:
- ChEMBL ID: CHEMBL5793140
- Molecular weight: 500.56
- Heavy atoms: 37
- Hydrogen bond donors: 3
- Hydrogen bond acceptors: 8
- TPSA: 149.39
- LogP: 2.89
- Rotatable bonds: 5
- Ring count: 6
- Aromatic rings: 5
- Formal charge: 0
- Fraction Csp3: 0.35
- QED: 0.33

## Molecule Similarity
- Weighted Tanimoto: 0.76

Answer: 8.8