反应详情

To a pre-cooled (−45° C.) solution of (2R,3R)-2-(4-cyanonaphthalen-1-ylamino)-3-hydroxybutanoic acid (1.50 g, 5.55 mmol) and 4-cyanobenzohydrazide (894 mg, 5.55 mmol) in anhydrous THF (80 mL) was added 1-Hydroxybenzotriazole monohydrate (850 mg, 5.55 mmol) and N-(3-Dimethylaminopropyl)-N′-ethylcarbodimide-HCl (2.13 g, 11.1 mmol) at −45° C. followed by triethylamine (1.55 mL, 11.1 mmol). The reaction mixture warmed to room temperature and stirred for 24 h, then quenched with 5% aq. citric acid (300 mL). The solution was extracted with EtOAc (300 mL). The organic extract was washed with 5% aq. citric acid (2×150 mL), sat. aq. NaHCO3 (3×150 mL), H2O (2×150 mL), dried (Na2SO4), filtered and concentrated under reduced pressure to provide the title compound as a light brown solid (2.12 g, 92%): 1H NMR (400 MHz, DMSO-d6, δ in ppm) 10.84 (s, 1H), 10.44 (s, 1H), 8.48 (d, J=8.8 Hz, 2H), 8.04-7.93 (m, 4H), 7.91 (d, J=8.2 Hz, 1H), 7.74 (t, J=6.8 Hz, 1H), 7.62 (t, J=7.2 Hz, 1H), 6.92 (d, J=8.2 Hz, 1H), 6.75 (d, J=8.2 Hz, 1H), 5.25 (d, J=4.5 Hz, 1H), 4.32-3.97 (m, 3H), 1.32 (d, J=6.1 Hz, 3H).

1. customquenched with 5% aq. citric acid (300 mL)
2. extractionThe solution was extracted with EtOAc (300 mL)
3. extractionThe organic extract
4. washwas washed with 5% aq. citric acid (2×150 mL), sat. aq. NaHCO3 (3×150 mL), H2O (2×150 mL)
5. dry with materialdried (Na2SO4)
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure