7.3.3. Special Plot: pKa Performance Graph

7.3.3. Special Plot: pKa Performance Graph

1. Open the SAMPL6_pKa.smi file from the ADMET Predictor application directory file and generate the ADMET Predictor predictions as described in the tutorial Interactive Input: SMILES. This file contains compounds and experimental pKa data used in SAMPL6 competition (Isik 2021) of the pK_a predictive models.

2. Expand the 2D scatter plot (Chart 2, bottom pane) on the right side. Click the pKa button outlined below in red

1. In the new dialog box press the Ctrl button and select experimental pKa named "pKa1 mean", "pKa2 mean", and "pKa3 mean". Click OK.

1. Click the Linear Fit button. You should see the "Predicted pKa" (by the S+pKa model) vs. "Observed pKa" plot along with performance statistics.

1. Use Export... dialog to export the matched predicted and observed pK_a.

NOTE:

For detailed information about the indicated topic, see the referenced chapters, section, and/or appendices in the ADMET Predictor User’s Manual:

• The science of multiprotic ionization, last paragraph about pK_a matching.