反应详情

Prolyl-proline hydrobromide (4.24 g) is dissolved in a mixture of dimethylformamide (40 ml) and triethylamine (2.8 ml). Benzyloxycarbonyl-isoleucine p-nitrophenyl ester (9.27 g) and 1-hydroxybenzotriazole (3 g) are added and the mixture is stored at room temperature for 16 hours. Dimethylaminopropylamine (1 ml) is added and after 2 hours the solvent is removed in vacuo. The residue is dissolved in ethyl acetate (200 ml) and washed sequentially with 0.1 N hydrochloric acid, and water. The organic phase is dried over magnesium sulfate and concentrated to dryness in vacuo to yield 13.8 g solid. This material is applied to a silica gel column (300 g) in ethyl acetate and eluted with the same solvent. The fractions containing the desired above-titled tripeptide are pooled and concentrated to dryness.

1. customis removed in vacuo
2. dissolutionThe residue is dissolved in ethyl acetate (200 ml)
3. washwashed sequentially with 0.1 N hydrochloric acid, and water
4. dry with materialThe organic phase is dried over magnesium sulfate
5. concentrationconcentrated to dryness in vacuo