Objectives This study aimed at measuring the lipophilicity and ionization constants of diastereoisomeric dipeptides, interpreting them in terms of conformational behavior, and developing statistical models to predict them. Methods A series of 20 dipeptides of general structure NH 2-LX-(L or D)-His-OMe was designed and synthetized. Their experimental ionization constants (pK 1, pK 2 and pK 3) and lipophilicity parameters (log PN and log D ...