A mixture of 4-(4-bromo-2-fluorophenylamino)-1-methyl-6-oxo-1,6-dihydropyridine-3-carboxylic acid (0.078 g, 0.229 mmol), EDCI (0.13 g, 0.69 mmol), and HOBt (0.093 g, 0.69 mmol) in DMF (5 mL) was stirred for 30 minutes. O-Cyclopropylmethyl-hydroxylamine (0.060 g, 0.69 mmol) was added followed by Et3N (0.096 mL, 0.69 mmol). After 1 hour, the reaction mixture was diluted with EtOAc and washed with saturated NH4Cl solution, saturated NaHCO3 solution and brine. The organic layer was dried (MgSO4) and concentrated to yield 83 mg (89%) clean desired product. MS APCI (+) m/z 410, 412 (M+, Br pattern) detected; 1H NMR (400 MHz, DMSO-d6) δ 11.57 (s, 1H), 9.42 (s, 1H), 8.10 (s, 1H), 7.67 (d, 1H), 7.43 (m, 2H), 3.70 (d, 2H), 3.35 (s, 3H), 1.11 (m, 1H), 0.54 (m, 2H), 0.27 (m, 2H).
