Stratified Sampling We applied a stratified sampling approach within each cluster to capture a wide range of compounds with varying distances from the cluster centers. The compounds in each cluster were divided into 10 strata based on their distance from the cluster center. This stratification allowed us to account for internal variability within each cluster by sampling both near-center and far-center compounds. A random selection was made from each stratum, ensuring that the entire chemical space within each cluster was adequately represented.