反应详情

25 g of H-Ala-OMe, HCl and 66 g. of Boc-Ser-ONb are dissolved in 500 ml DMF. The product is cooled in an ice bath and 25 ml of NEM, 24 g of N-hydroxy benzotriazole are added with magnetic stirring and the pH is maintained at 6.5 or 7 by addition of NEM. The product is stirred for 18 hrs. at ambient temperature. After TLC monitoring, the medium is evaporated to 90% (0.1 mm Hg-35° C.). The oil obtained is dissolved in 1.500 ml of chloroform, the product is washed with a solution of saturated sodium chloride (twice), 5% sulfate/potassium bisulfate solution (3 times), saturated sodium bicarbonate (5 times). The solution is dried over Na2SO4 and evaporated to dryness. An oil is obtained which is dried to constant weight (30°-0.1 mm Hg).

1. temperatureThe product is cooled in an ice bath
2. temperaturethe pH is maintained at 6.5 or 7 by addition of NEM
3. stirringThe product is stirred for 18 hrs
4. customat ambient temperature
5. customAfter TLC monitoring, the medium is evaporated to 90% (0.1 mm Hg-35° C.)
6. customThe oil obtained
7. washthe product is washed with a solution of saturated sodium chloride (twice), 5% sulfate/potassium bisulfate solution (3 times), saturated sodium bicarbonate (5 times)
8. dry with materialThe solution is dried over Na2SO4
9. customevaporated to dryness
10. customAn oil is obtained which
11. customis dried to constant weight (30°-0.1 mm Hg)