To a solution of 4-(3-amino-6-((1R,3R,4R)-3-fluoro-4-hydroxycyclohexyl)pyrazin-2-yl)-2-fluorobenzoic acid (18 mg, 0.052 mmol) in DMF (0.52 mL) was added (S)-2-amino-2-(3-fluoro-5-iodophenyl)ethanol hydrochloride (19.6 mg, 0.062 mmol), HOAt (10.52 mg, 0.077 mmol), EDC (19.76 mg, 0.103 mmol), and DIEA (27 μl, 0.155 mmol). The reaction mixture was stirred for 15 h. After water was added, the reaction mixture was extracted with EtOAc and the organic layer was washed with water twice. The organic layer was separated and dried over Na2SO4, filtered off and concentrated in vacuo. The crude product was purified by flash chromatography eluting with 0-100% EtOAc/heptane to provide 15.8 mg of 4-(3-amino-6-((1R,3R,4R)-3-fluoro-4-hydroxycyclohexyl)pyrazin-2-yl)-2-fluoro-N—((S)-1-(3-fluoro-5-iodophenyl)-2-hydroxyethyl)benzamide as a free base (50%). LCMS (m/z): 613.1 (MH+), 0.74 min; 1H NMR (400 MHz, CD3OD) δ ppm 7.89-7.69 (m, 2H), 7.66-7.47 (m, 3H), 7.39-7.26 (m, 1H), 7.12 (d, J=9.4 Hz, 1H), 5.05 (t, J=5.9 Hz, 1H), 4.43-4.14 (m, 1H), 3.84-3.66 (m, 2H), 3.64-3.45 (m, 1H), 2.74 (t, J=11.7 Hz, 1H), 2.17 (td, J=3.1, 6.0 Hz, 1H), 2.05-1.87 (m, 1H), 1.84-1.66 (m, 2H), 1.65-1.47 (m, 1H), 1.47-1.27 (m, 1H).
