Reaction Steps
2-[3-(4-Methanesulfonyl-phenylcarbamoyl)-2,5-dimethyl-pyrrol-1-yl]-benzoic acid methyl ester was prepared from methyl anthranilate in a manner similar to that described for Examples 1G. 1H-NMR (DMSO-d6): δ 9.58 (1H, s), 7.83 (2H, d, J=8.8), 7.79 (1H, dd J=7.8, 1.5), 7.63 (2H, d, J=7.8), 7.58 (1H, dd, J=7.8, 1.5). 7.48 (1H, td, J=7.6, 1.3), 7.21 (1H, dd, J=7.8, 1.0), 7.15 (1H, s), 6.42 (1H, d, J=1.0), 3.43 (3H, s), 2.96 (3H, s), 1.94 (3H, s), 1.66 (3H, s); MS (ESI): 427 (MH4). To a solution of 2-[3-(4-methanesulfonyl-phenylcarbamoyl)-2,5-dimethyl-pyrrol-1-yl]-benzoic acid methyl ester (0.7 g, 1.6 mmol) in MeOH/THF (8 mL: 16 mL) was added LiOH (0.275 g, 6.4 mmol). After stirring 14 h at room temperature, the reaction mixture was concentrated in vacuo. The crude reaction mixture was re-dissolved in water and washed with EtOAc. The water layer was separated and then acidified with 1N HCl. The resulting suspension was extracted twice with EtOac. The combined extracts were dried (Na2SO4) and concentrated in vacuo to provide the title compound (0.67 g, 99%) as a white solid. 1H-NMR (DMSO-d6): δ 13.03 (1H, s), 9.81 (1H, s), 8.06 (2H, d, J=9.1), 8.02 (1H, d J=7.8), 7.87 (2H, d, J=8.6), 7.78 (1H, t, J=7.3). 7.68 (1H, t, J=7.8), 7.39 (1H, d, J=7.6), 6.65 (1H, s), 3.20 (3H, s), 2.23 (3H, s), 1.92 (3H, s); MS (ESI): 413 (MH+).
