反应详情

(2R,3R)-2-(3-chloro-4-cyano-2-methylphenylamino)-3-hydroxybutanoic acid (663 mg, 2.5 mmol) (intermediate 3a) and 3-hydroxy-benzohydrazide (376 mg, 2.5 mmol) were coupled similarly to the procedure used for intermediate 1b. After column chromatography (5% methanol/EtOAc) the title compound was isolated as a white solid (615 mg, 62%). 1H NMR (500 MHz, acetone-d6, δ in ppm) 9.79 (br s, 1H), 8.81 (br s, 1H), 7.45 (ad, J=8.7 Hz, 1H), 7.38 (m, 2H), 7.27 (t, J=7.87 Hz, 1H), 7.02 (m, 1H), 6.71 (d, J=8.7 Hz, 1H), 5.61 (m, 1H), 4.23 (m, 1H), 4.14 (m, 1H), 2.29 (s, 3H), 1.37 (d, J=6.5 Hz, 3H).