## Endpoint to Predict
- Endpoint scope: assay
- Measurement type: IC50
- Label type: continuous
- Binary semantics: pchembl
- Assay description: Rat FAAH Inhibition Assay: Active rat FAAH protein (30-579) was isolated as described in the literature. The coding sequence of amino adds 30-579 of rat FAAH were cloned into the expression vector pET28a to provide an N-terminal His-tag. Following expression, the His-tagged FAAH (30-579) was isolated using a method based on Patricelli at al., 1998; Biochemistry vol 37, p 15177 with a combination of chelating sepharose, heparin sepharose and size exclusion chromatography.FAAH activity was determined by measuring the liberation of the highly fluorescent 7-amino, 4-methyl Coumarin (AMC) generated during hydrolysis of the substrate Arachidonoyl 7-Amino, 4-methyl Coumarin Amide (AAMCA) by FAAH. Inhibition of FAAH activity was determined as a percentage reduction of the fluorescence determined in the absence of compound.The assay was carried out in black-walled, clear bottom, 384-well plates. 27.5 μl of FAAH protein (in FAAH assay buffer: 50 mM Hepes, 0.01% Triton X-100, 1 mM EDTA, 0.5 mg/ml BSA (fatty-acid-free), pH 8.2) was pre-incubated, at 120 nM, with increasing concentrations of compounds (2.5 μl in 100% DMSO) for 0, 1 or 3 hours at room temperature. 2.5 μl of DMSO was added for total controls (100% FAAH activity) and 2.5 μl of URB-597, a known inhibitor of FAAH activity, (at a final, saturating, concentration of 10 μM) was used for non-specific controls (0% FAAH activity). 20 μl of 7.5 μM AAMCA substrate (in FAAH assay buffer) was then added to all wells and incubated at room temperature for a further 1.5 hours. Fluorescence was determined at an excitation wavelength of 355 nm and an emission wavelength of 460 nm using a Flexstation plate reader (Molecular Devices, UK). Inhibition of FAAH activity, by the compounds, was determined as the percentage reduction in relative fluorescence units (RFU) compared to the total controls (in the absence of compound) minus the non-specific controls. IC50 values were determined, from 10-point dose response curves, in XL-Fit using a 4-Parameter Logistic Model (Sigmoidal Dose-Response Model).
- Target name: Fatty-acid amide hydrolase 1
- Target type: SINGLE PROTEIN
- Target organism: Rattus norvegicus

## Reference Molecule A
- Canonical SMILES: O=C(Nc1cccc(F)c1)N1CC(Oc2ccc(-c3ccccc3)cc2)C1
- Properties:
- ChEMBL ID: CHEMBL3677686
- Molecule type: Small molecule
- Molecular weight: 362.4
- Heavy atoms: 27
- Hydrogen bond donors: 1
- Hydrogen bond acceptors: 2
- TPSA: 41.57
- LogP: 4.79
- Rotatable bonds: 4
- Ring count: 4
- Aromatic rings: 3
- Formal charge: 0
- Fraction Csp3: 0.14
- QED: 0.73

## Known Reference Result on This Endpoint
- Molecule A clean result: median pChEMBL = 6.55
- This result is provided as context for predicting Molecule B on the same endpoint.

## Reference Molecule A Other ChEMBL Evidence
- type IC50; relation =; value 279; units nM; pChEMBL 6.55; comment 1000325

## Query Molecule B
- Canonical SMILES: O=C(Nc1ccccc1F)N1CC(Oc2ccc(-c3ccccc3)cc2)C1
- Properties:
- ChEMBL ID: CHEMBL3677687
- Molecule type: Small molecule
- Molecular weight: 362.4
- Heavy atoms: 27
- Hydrogen bond donors: 1
- Hydrogen bond acceptors: 2
- TPSA: 41.57
- LogP: 4.79
- Rotatable bonds: 4
- Ring count: 4
- Aromatic rings: 3
- Formal charge: 0
- Fraction Csp3: 0.14
- QED: 0.73

## Molecule Similarity
- Weighted Tanimoto: 0.7

Answer: 7.11