To a mixture of Example 91b (80.0 mg, 0.246 mmol) and triethylamine (74.6 mg, 0.738 mmol) in dichloromethane (4 mL) was added dropwise 2-fluoroethanesulfonyl chloride (144 mg, 0.984 mmol), and the reaction mixture was stirred at about ambient temperature for about 1 hour. The reaction mixture was neutralized with saturated aqueous ammonium chloride solution (50 mL) and the mixture was extracted with ethyl acetate (3×50 mL). The combined organic layers were washed with saturated aqueous sodium chloride solution, dried (anhydrous magnesium sulfate), filtered, and concentrated. The residue was purified by preparative HPLC (C18, 10-80% acetonitrile in 0.1% TFA/water) to provide the title compound (7.0 mg, 6.5% yield). 1H NMR (300 MHz, CDCl3) ppm 11.54 (bs, 1H), 7.45 (t, J=2.8 Hz, 1H), 7.19 (s, 1H), 6.88 (d, J=8.7 Hz, 1H), 6.73 (d, J=2.7 Hz, 1H) 6.67 (dd, J=3.1, 8.8 Hz, 1H), 6.40 (dd, J=2.0, 2.7 Hz, 1H), 4.76 (m, 1H), 3.82 (s, 3H), 3.85-3.62 (m, 8H), 2.97 (bs, 1H), 2.24-1.85 (m, 2H). MS (ESI+) m/z 436.2 (M+H)+.
