HOAt → (2R,4S)-ethyl 5-(biphenyl-4-yl)-4-(2-methoxythiazole-5-carboxamido)-2-methylpentanoate

Participants

Reaction Steps

To a solution of 2-methoxythiazole-5-carboxylic acid (101 mg, 0.64 mmol) in DMF (6 mL) is added HOAt (107 mg, 0.58 mmol), EDCl (133 mg, 0.69 mmol), and TEA (0.48 mL, 3.47 mmol). The crude is stirred at room temperature for 15 mins. To this crude is added (2R,4S)-ethyl 4-amino-5-(biphenyl-4-yl)-2-methylpentanoate hydrochloride salt. The crude is stirred at room temperature for overnight. The crude is quenched with 1 N HCl and water, diluted in EtOAc. The organic layer is washed with brine, dried over MgSO4, filtered, and concentrated. The residue is purified via flash column chromatography using 30% EtOAc/heptane to 70% EtOAc/heptane to give (2R,4S)-ethyl 5-(biphenyl-4-yl)-4-(2-methoxythiazole-5-carboxamido)-2-methylpentanoate (170 mg). HPLC retention time 1.94 minutes (condition A); MS 453.3 (M+1); 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.18 (d, J=7.1 Hz, 3H), 1.23 (t, J=7.1 Hz, 3H), 1.71 (ddd, J=14.0, 9.9, 3.9 Hz, 1H), 1.88-2.04 (m, 1H), 2.56-2.73 (m, 1H), 2.78-2.96 (m, 1H), 2.96-3.09 (m, 1H), 4.09 (s, 3H), 4.09-4.18 (m, 2H), 4.30-4.47 (m, 1H), 6.15 (d, J=8.1 Hz, 1H), 7.27 (d, J=6.8 Hz, 2H), 7.29-7.36 (m, 1H), 7.42 (t, J=7.6 Hz, 2H), 7.49 (s, 1H), 7.53 (d, J=8.1 Hz, 2H), 7.57 (d, J=7.3 Hz, 2H).

Provenance & Evidence