Z-Val-ONp → Z-Val-Gly-Ala-Pro-OtBu

Participants

Reaction Steps

3.73 g of Z-Val-ONP and 2.99 g of H-Gly-Ala-Pro-OtBu in 12 ml of ethyl acetate are stirred for one hour at 0°C and 20 hours at room temperature. After dilution with ethyl acetate the mixture is washed with 50 % saturated potassium carbonate solution and water, dried over sodium sulphate and evaporated at 30°C in a waterpump vacuum. The oil is crystallised from methanol-water. Melting point 73°-75°C. In a thin layer chromatogram on silica gel Rf = 0.42 in the system tolueneacetone (1:1) and Rf = 0.46 in the system chloroform-methanol (9:1).

Provenance & Evidence