Boron trifluoride etherate → N-(4-{1-[1-(2-methoxyethyl)-1H-pyrrol-2-yl]-methyl}-phenyl)-N-methyl-benzenesulfonamide

To a solution of 16 mg (0.04 mmol) of N-(4-{1-hydroxy-1-[1-( 2-methoxyethyl)-1H-pyrrol-2-yl]-methyl}-phenyl)-N-methyl-benzenesulfonamide (Example 7) in 1.5 mL CH2Cl2 at 0° C. were added 620 μL (3.88 mmol) of triethylsilane followed by 100 μL (0.79 mmol) of boron trifluoride diethyl etherate dropwise. The mixture was warmed to room temperature and stirred for 2.5 h. After this time, the reaction mixture was cooled to 0° C., quenched by the addition of a saturated aqueous solution of sodium bicarbonate, allowed to warm to room temperature, and extracted with EtOAc. The combined organic layers were dried over Na2SO4, filtered and the filtrate was concentrated. The residue was purified by chromatography on silica gel (hexanes:EtOAc, 3:1) to give the title compound.