A study of the relationship between the structure of homologous series of oxprenolol at various pH values.

Stability of series of O-acyl esters of oxprenolol prepared as potential pro-drugs, is investigated over the pH range 0.4-10 at 37 degrees C. Maximum stability of all esters occurred at pH 3-4. The most stable derivative was found to be pivaloyl ester. The relationship between Charton Steric parameters (v) and the catalytic rate constant of hydrolysis is investigated.