The physicochemical representation was drastically different from that obtained using ECFP (see Figure ). Firstly, it contained a "hydrophilic" region with 1st UMAP coordinate > 10, which was covered almost exclusively by EnamineRT compounds, with only a few occasional exceptions from the METLIN SMRT dataset. Secondly, there were over ten well-separated regions containing smaller conglomerates inside them. METLIN SMRT covered about 20-30% less chemical space in the physicochemical representation (as compared to EnamineRT) and was particularly enriched with lipophilic compounds having 2nd UMAP coordinate < 5. In other words, EnamineRT covered larger region of chemical space as compared to METLIN SMRT dataset.