Fig. 2: Exemplar cyclic diketone compounds studied in this work and the performance of Marvin versus Experiment.
From: Aqueous pKa prediction for tautomerizable compounds using equilibrium bond lengths
a pKa data for compounds of the dataset used were procured from both Syngenta’s database and literature sources. The pKa values of 17 compounds were also measured for the purpose of this work. Each compound either contains a 1,3-cyclohexanedione (1,3-CHD) or 1,3-cyclopentanedione group (1,3-CPD), examples of which are shown in blue and green, respectively. Substituent variation occurs at 2, 4, 5 and/or 6 position on 1,3-CHD, and 2, 4 and/or 5 for 1,3-CPD. The full set of structures and experimental pKa values can be found in Supplementary Table 1 of the SI. b Experimental (orange) pKa values across the series o1-o8, tk1-tk15 and dk1-dk12, are compared with Marvin predictions with the “consider tautomers/resonance” option (magenta) and without this option (blue). Values are in excess of 14 log units for the acidic proton at C2 (labelled for 1,3-cyclohexanedione) for o2, o4, o5, o6 and o8 and values for o1, o3 and o7 correspond to C4/C6.
