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Epik: Rapid and robust pK_a predictions

Combining the proven reliability of Hammett and Taft methods with powerful tautomerization tools, Epik is the program of choice for accurate enumeration of ligand protonation states in biological conditions.

The Advantages of Empirical pK_a Prediction

Proper treatment of ligand protonation states is essential to lead discovery. The pK_a's of a drug's various functional groups play a critical role in determining its bioavailability and pharmacokinetic profile, while virtual screening software relies on correctly protonated structures in order to perceive the discrete interactions that drive ligand binding. However, many readily available libraries provide ligand structures in familiar tautomeric forms with all functional groups neutralized. These forms may not be highly populated under biological conditions, and are therefore inappropriate for property prediction or virtual screening experiments.

Epik provides a time-tested solution to these problems, designed specifically to work within the context of contemporary drug discovery workflows. Using Hammett and Taft methods in conjunction with ionization and tautomerization tools, Epik is able to rapidly and reliably predict pK_a values and return all chemically sensible structures.