反应详情

To a solution of pyrazine-2-carboxylic acid (0.570 g, 4.60 mmol) in CH2Cl2 (50 mL) was added EDC (0.960 g, 5.01 mmol) and HOBt (0.620 g, 4.60 mmol) at room temperature. The mixture was stirred for 10 min, and 3-(2-aminomethyl-4-hydroxy-phenyl)-propionic acid tert-butyl ester (1.05 g, 4.18 mmol) was added. The reaction mixture was stirred for 18 h at room temperature, treated with water (50 mL), and extracted with CH2Cl2 (2×50 mL). The combined organic layers were dried (Na2SO4), concentrated, and purified by silica gel chromatography (EtOAc/hexanes, 1:1 to 1:0) to obtain the title compound (1.05 g, 70%). 1H NMR (400 MHz, CDCl3): δ 1.40 (s, 9H), 2.52 (t, 2H, J=7.6 Hz), 2.91 (t, 2H, J=7.6 Hz), 4.66 (d, 2H, J=6.4 Hz), 6.73 (dd, 1H, J=2.9, 7.8 Hz), 6.83 (d, 1H, J=2.4 Hz), 7.07 (d, 1H, J=8.3 Hz), 8.17 (br s, 1H), 8.49 (dd, 1H, J=1.5, 2.4 Hz), 8.73 (d, 1H, J=2.4 Hz), 9.41 (d, 1H, J=1.5 Hz). MS (ES) m/z 356.1 ([M−H]−).

1. stirringThe reaction mixture was stirred for 18 h at room temperature
2. extractionextracted with CH2Cl2 (2×50 mL)
3. dry with materialThe combined organic layers were dried (Na2SO4)
4. concentrationconcentrated
5. custompurified by silica gel chromatography (EtOAc/hexanes, 1:1 to 1:0)