An additional requirement was that a minimum of 100 milligrams of solid was available in the compound stores. From this set of ~77,000 compounds, 88 were selected which contained two widely separated polar groups (separated by greater than three bonds), scaffolds often found in screening hits, and/or the presence of sulfonamide or sulfone (due to a lack of public ΔGtransfer data for such compounds ). Three of the selected compounds were matched molecular sets (SAMPL8-7, 8-9, and 8-17), with the intention of determining if there is a measurable role that small changes on a given scaffold would have on the experimental data. The entire list of compounds selected had a molecular weight ranging from 165 to 403 Dalton (Table ) and zero to six rotatable bonds. Of these 88 compounds, some failed with visually observable degradation, while many others, which did progress to HTE testing, failed to exhibit a measurable pKa.