反应详情

A solution of 1.20 g of the crude product from stage 4 in 7 ml of acetic anhydride and 7 ml of acetyl chloride was stirred for 5 hours at 70° C. and then concentrated by evaporation in vacuo. The residue was taken up in 20 ml of methanol and stirred for 1 hour with Amberlyst A-21 ion exchanger. After filtration the filtrate was concentrated by evaporation in vacuo and the residue was purified by flash chromatography with chloroform/methanol (4/1) as eluent. The free base of the title compound thereby obtained was dissolved in 4 ml of methanol and 0.5 ml of a saturated solution of HCl gas in diethyl ether followed by 150 ml of diethyl ether were added to the solution. The salt formed was separated and dried in vacuo, 0.29 g (23% of theory referred to L-glutamine in stage 4) of the title compound being obtained.

1. concentrationconcentrated by evaporation in vacuo
2. filtrationAfter filtration the filtrate
3. concentrationwas concentrated by evaporation in vacuo
4. customthe residue was purified by flash chromatography with chloroform/methanol (4/1) as eluent