Calcium Acetate → N-benzyloxycarbonyl (beta-benzyl)-L-aspartyl-L-phenylalanine methyl ester

Participants

Reaction Conditions

Reaction Steps

A 100 mg amount of Thermoase and 100 mg of an inhibitor for proteolytic enzyme obtained from the potato were admixed with 10 ml of tris-hydrochloric acid buffer solution (pH 8.0) containing 2.0 × 10-2M of calcium acetate. The mixture was stirred at 30° C. for 10 minutes. The insoluble material was removed by filtering the solution through a glass filter (G-3). The filtrate was mixed with 715 mg (2.00 mmol) of N-benzyloxycarbonyl-(β-benzyl)-D,L-aspartic acid and 215 mg (1.00 mmol) of L-phenylalanine methyl ester and then 1N NaOH was added to the filtrate to adjust the pH to 7.5. The reaction was carried out with stirring at 39° C. for 17 hours. The resulting white precipitate was treated in accordance with the process of Example 1 whereby 411 mg (yield of 79.2%) of N-benzyloxycarbonyl-(β-benzyl)-L-aspartyl-L-phenylalanine methyl ester having an [α]D23 = -12.5 (C=1.0 dimethylformamide)

Provenance & Evidence