反应详情

N-(N-Benzyloxycarbonyl-L-prolyl)-L-leucine (4.6 g), glycine ethyl ester hydrochloride (1.8 g) and triethylamine (1.78 ml) are dissolved in dry chloroform (40 ml) and thereto is added 1-(p-toluenesulfonyloxy)-6-nitro-1,2,3-benzotriazole (4.25 g) under ice-cooling and the mixture is stirred for 1 hour. After allowing to stand overnight, to the mixture are added water and ethyl acetate. The ethyl acetate layer is washed with 1 N aqueous ammonia containing 5% NaCl (six times), water, 1 N hydrochloric acid and water in order, dried over anhydrous magnesium sulfate, and then the solvent is distilled off. The resulting residue is washed with ether-petroleum ether to give N-[N-(N-benzyloxycarbonyl-L-prolyl)-L-leucyl]glycine ethyl ester (3.0 g), melting point: 149°-150° C.

1. temperaturecooling
2. waitto stand overnight, to the mixture
3. washThe ethyl acetate layer is washed with 1 N aqueous ammonia containing 5% NaCl (six times), water, 1 N hydrochloric acid and water in order
4. dry with materialdried over anhydrous magnesium sulfate
5. distillationthe solvent is distilled off
6. washThe resulting residue is washed with ether-petroleum ether