4.1. Data Collection. The dataset was generated from in-house screening of several commercially available DEL libraries (openDEL from Hitgen) against soluble epoxide hydrolase (sEH). The DEL screen was performed as previously described in Clark et al. Briefly, Nterm his-tagged human Soluble Epoxide Hydrolase (sEH) protein (1 uM, N-term His-tagged) was incubated with pooled DEL libraries in a 100 uL reaction (50 mM HEPES (pH 7.4); 150 mM NaCl; 0.01% Tween-20; 10 mM Imidazole; 1 mM TCEP; 0.1 mg/mL ssDNA). Post-incubation, the protein was captured by magnetic beads (Invitrogen Dynabeads His-Tag, and Pierce Ni-NTA magnetic beads), and the samples washed with buffer. Each round of selection was completed by a heat elution (95°C, 10 min) to separate protein from bound molecules. A new round was initiated by introduction of fresh protein and the process repeated for a total of 3 rounds. In parallel, a matrix-binding only sample was included to account for non-specific binding. Post-selection, samples were PCR amplified and sequenced on a next-generation sequencing platform. 4.2. Data Curation. We compiled input files after experiment as comma-separated values (CSVs) containing the SMILES of each composite structure, its experimentally determined read count and the SMILES of its constituent building blocks. In some cases, the SMILES strings for building blocks included the protecting groups used during synthesis which would be removed in the process of constructing full compounds.