A solution of 6-(adamantan-1-ylmethoxy)-5-cyclopropyl-N-((2-methoxyethyl)-sulfonyl)nicotinamide (0.19 g, 0.42 mmol) in anhydrous dichloromethane (10 mL) at 0° C. was treated with boron tribromide (0.079 mL, 0.84 mmol) under nitrogen. The reaction mixture was stirred for 25 minutes and then diluted with ethyl acetate (50 mL). The mixture was washed with 1 M aqueous hydrochloric acid solution (2×30 mL), brine (30 mL); dried over anhydrous sodium sulfate; filtered and concentrated in vacuo to provide the title compound (0.18 g, quant.): 1H NMR (300 MHz, DMSO-d6) δ 11.91 (br s, 1H), 8.45 (d, J=2.3 Hz, 1H), 7.70 (d, J=2.3 Hz, 1H), 4.95 (br s, 1H), 3.93 (s, 2H), 3.80-3.73 (m, 2H), 3.65-3.58 (m, 2H), 2.07-1.98 (m, 1H), 1.98-1.90 (m, 3H), 1.73-1.57 (m, 12H), 0.98-0.90 (m, 2H), 0.76-0.70 (m, 2H); MS (ES+) m/z 435.2 (M+1).
