3-[3-bromo-4-[(2,4-difluorobenzyl)oxy]-6-methyl-2-oxopyridin-1(2H)-yl]-4-methylbenzoic acid (from Step 4 above) (1.9 g, 4.10 mmol) was dissolved in 20 ml of CH2Cl2. Ethanolamine (297 μl, 4.92 mmol) was added, followed, in order, by EDCI (0.764 g, 4.92 mmol), 1-hydroxybenzotriazole (0.6659, 4.92 mmol) and triethylamine (1.14 ml, 8.20 mmol). The reaction was stirred at room temperature overnight. The reaction was quenched with NH4Cl and extracted 3 times with ethyl acetate. The combined organic layer was then washed with saturated NaHCO3 (aq.) and extracted 3 times with ethyl acetate. The organic layers were combined and washed with H2O and extracted 3 times with ethyl acetate. The organic layers were combined and dried over Na2SO4 and evaporated. The resulting residue was triturated with diethyl ether/hexane to obtain a solid, which was dried in vacuo to give a white solid (15 g, 72%). 1H NMR (300 MHz, CDCl3) δ 7.93 (dd, J=7.85, 1.61 Hz, 1H), 7.65 (d, J=1.61 Hz, 1H), 7.62 (app q, J=8.26 Hz, 1H), 7.40 (d, J=8.06 Hz, 1H), 7.39-7.30 (m, 1H), 7.03-6.97 (m, 1H), 6.88-6.81 (m, 1H), 6.25 (s, 1H), 5.20 (s, 2H), 3.70-3.52 (m, 1H), 3.16-3.12 (m, 2H), 2.10 (s, 3H), 1.98 (s, 3H); ES-MS m/z 507 (M+H). ES-HRMS m/z 507.0719 (M+H calcd for C23H22BrF2N2O4 requires 507.0726).
