Triethylamine → Z-Glu(Val-Gly-OBzl)-OBzl

Participants

Reaction Steps

H-Val-Gly-OBzl•HCl and Z-Glu-OBzl (5.57 g, 15.0 mmol) described above were dissolved in methylene chloride (50 ml), and the solution was kept at 0° C. Triethylamine (2.30 ml, 16.5 mmol), HOBt (1-hydroxybenzotriazole, 2.53 g, 16.5 mmol), and WSC•HCl (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride, 3.16 g, 16.5 mmol) were added to the solution, and the mixture was stirred at room temperature overnight for 2 days. The reaction solution was concentrated under reduced pressure, and the residue was dissolved in heated ethyl acetate (1,500 ml). The solution was washed with water (200 ml), 5% citric acid aqueous solution (200 ml× twice), saturated brine (150 ml), 5% sodium bicarbonate aqueous solution (200 ml× twice), and saturated brine again (150 ml). The organic layer was dried over anhydrous magnesium sulfate, magnesium sulfate was removed by filtration, and the filtrate was concentrated under reduced pressure. The precipitated crystal was collected by filtration and dried under reduced pressure to obtain Z-Glu(Val-Gly-OBzl)-OBzl (6.51 g, 10.5 mmol) as a white crystal.

Provenance & Evidence