反应详情

温度

4 °C

To a mixture of (R)-1-[3-(1-tert-butoxycarbonyl-4-piperidyl)propionyl]-3-piperidinecarboxylic acid (20.0 g), 2(S)-benzyloxycarbonylamino-β-alanine methyl ester hydrochloride (17.2 g) and 1-hydroxybenzotriazole (8.07 g) in N,N-dimethylformamide (200 ml) was added dropwise 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (10.9 ml) at 0° C. The mixture was stirred at 4° C. for 15 hours, then poured into ice water (500 ml), and extracted with ethyl acetate (500 ml×2). The combined organic layer was successively washed with water, saturated aqueous NaHCO3 and brine, dried over Na2SO4, and evaporated in vacuo. The residue was chromatographed on silica gel eluting with n-hexane-ethyl acetate (from 1:1 to ethyl acetate only) to give N-[(R)-1-[3-(1-tert-butoxycarbonyl-4-piperidyl)propionyl]-3-piperidylcarbonyl]-2(S)-benzyloxycarbonylamino-β-alanine methyl ester (30.5 g) as a colorless oil.

1. extractionextracted with ethyl acetate (500 ml×2)
2. washThe combined organic layer was successively washed with water, saturated aqueous NaHCO3 and brine
3. dry with materialdried over Na2SO4
4. customevaporated in vacuo
5. customThe residue was chromatographed on silica gel eluting with n-hexane-ethyl acetate (from 1:1 to ethyl acetate only)