Only molecules with the elements: H, B, C, N, O, F, Si, P, S, Cl, Se, Br, and I were selected. The remaining compounds were neutralized and reionized to generate a canonical tautomer and remove duplicates. If present, the stereochemistry information was preserved only for the compounds designed de novo. The scoring function was established with a range of seven descriptors (values summarized in Table in the Supplementary Material) and a penalized substructure matching for nucleoside scaffolds (Figure ).