反应详情

580 mg of (S)—N-Boc-3-aminooctanoic acid prepared in the [2], 420 mg of L-threonine methyl ester hydrochloride, 1089 mg of Bop reagent, and 333 mg of HOBt were dissolved in 4.5 mL of dehydrated DMF, 0.97 mL of triethylamine was added with stirring under cooling with ice, stirred for 30 minutes under cooling with ice, and then stirred overnight at room temperature. 70 mL of ethyl acetate was added to the reaction solution obtained, washed with 10% aqueous solution of citric acid, 4% aqueous solution of sodium hydrogencarbonate, and saturated salt solution, dried over anhydrous sodium sulfate, followed by vacuum concentration. The residue was crystallized from ethyl acetate-hexane to obtain (S)—N-Boc-3-aminooctanoyl-L-threonine methyl ester. The yield was 544 mg. Analytical values are shown below.

1. temperatureunder cooling with ice
2. stirringstirred for 30 minutes
3. temperatureunder cooling with ice
4. stirringstirred overnight at room temperature
5. customobtained
6. washwashed with 10% aqueous solution of citric acid, 4% aqueous solution of sodium hydrogencarbonate, and saturated salt solution
7. dry with materialdried over anhydrous sodium sulfate
8. concentrationfollowed by vacuum concentration
9. customThe residue was crystallized from ethyl acetate-hexane