PROLINE AS NUCLEOPHILE IN KINETICALLY CONTROLLED PEPTIDE-SYNTHESIS CATALYZED BY ALCALASE IN 2-METHYL-2-PROPANOL

Procedures have been developed to synthesize proline-containing peptid es in good yields and high purities via a kinetically controled approa ch using an industrial alkaline protease, alcalase, as a catalyst in a nhydrous 2-methyl-2-propanol. The yield of the reaction was dependent on the structure of the acyl-donor and the water content in the solven t. Using tripeptide as an acyl donor, the yield was higher than that u sing dipeptide, and when amino acid derivatives were used the yield wa s the lowest. The yield was also dependent on the concentration of wat er present in the solvent. The higher the water concentration in the s olvent, the lower was the yield in the reaction. Both L-proline or D-p roline derivatives could be used as nucleophiles in the reaction.