1. The effect of pH, temperature, reactant concentration and reaction time has been investigated for the synthesis of benzylpenicillin, dl-alpha-hydroxybenzylpenicillin and d-alpha-aminobenzylpenicillin from 6-aminopenicillanic acid by the penicillin acylase of Escherichia coli. 2. Synthesis of penicillins from carboxylic acids proceeds most rapidly at pH5; with amides the optimum pH is higher ...
