To a solution of EXAMPLE 23B (1 g, 3.07 mmol) in anhydrous N,N-dimethylformamide (25 mL) was added 4-bromo-1H-pyrrole-2-carboxylic acid (0.67 g, 3.53 mmol), 1-ethyl-3-[3-(dimethylamino)propyl]-carbodiimide hydrochloride (0.77 g, 4 mmol), 1-hydroxybenzotriazole hydrate (0.61 g, 4 mmol) and triethylamine (0.4 g, 4 mmol). The reaction was stirred at room temperature overnight, and partitioned between ethyl acetate and brine. The organic phase was washed with brine, dried over anhydrous Na2SO4, filtered, and concentrated. The crude material was purified flash chromatography (20% ethyl acetate in hexane) to afford the title compound. LC-MS (ESI): m/z 500, 498 (M+H), RT: 2.37 min; 1H NMR (400 MHz, dimethylsulfoxide-d6): δ 3.75 (s, 3H), 3.78 (s, 3H), 4.51 (s, 2H), 4.77 (s, 2H), 6.53 (dd, J=6.4, 2.0 Hz, 1H), 6.60 (d, J=2.0 Hz, 1H), 7.09 (dd, J=1.2, 1.6 Hz, 1H), 7.15 (d, J=8.0 Hz, 1H), 7.60 (d, J=8.8 Hz, 2H), 8.21 (d, J=9.2 Hz, 2H), 12.02 (br s, 1H).
