5-Bromo-2-[[3-(3,4-dichlorophenyl)phenyl]sulfonylamino]benzenesulfonamide (70 mg, 0.13 mmol) was dissolved in DMF (700 μl), then phenylboronic acid (20 mg, 0.16 mmol) was added followed by the addition of 2M sodium carbonate solution (260 μl). The mixture was subjected to vacuum/argon (×3), tetrakis(triphenylphosphine)palladium (8 mg, 0.05 mol %) was added and the reaction was allowed to stir at 80° C. overnight. The cooled reaction mixture was filtered and was then purified by preparative HPLC (XTerra MS C8 column, acetonitrile/ammonium acetate buffer) to give the title compound (23 mg, 32%).
