In this work, we selected the ChemBridge-MPO database for use in training pre-trained models in CNSMolGen. This database was created by ChemBridge to provide a library of small molecule compounds for the CNS drug discovery and contains 504,853 high quality, PAINS-free small molecule compounds (). The CNS MPO is a well-recognized algorithm that assigns a score based on six key physicochemical properties (cLogP, cLogD, MW, TPSA, HBD and pKa) related to the blood-brain barrier (BBB) penetration, which is critical for CNS drug development . The CNS MPO score with scores ≥ 4.0 was widely used as a cut-off to select compounds for hit discovery in drug discovery programs in the CNS therapeutic area.