A solution of 1-benzenesulfonyl-2-[2-cyclopentyl-1-(4-methanesulfonyl-phenyl)-vinyl]-5-isopropoxy-1H-pyrrolo[2,3-b]pyridine (310 mg, 0.55 mmol) in tetrahydrofuran (0.5 mL) and a tetrabutylammonium fluoride solution in tetrahydrofuran (1 M, 4 mL, 4 mmol) was stirred at room temperature for 12 h. The reaction mixture was then diluted with ethyl acetate (150 mL), and washed with a saturated aqueous ammonium chloride solution, brine, dried over anhydrous sodium sulfate and concentrated in vacuo to afford 2-[2-cyclopentyl-1-(4-methanesulfonyl-phenyl)-vinyl]-5-isopropoxy-1H-pyrrolo[2,3-b]pyridine (236 mg, quant.) as a white solid: LC/MS m/e calcd for C24H28N2O3S [M+H]+ 425.57, observed 425.2.
