A solution of phenol (9.4 mg, 0.1 mmol) and 3-(8-amino-2-furan-2-yl-[1,2,4]triazolo[1,5-a]pyrazin-6-yl)-prop-2-yn-1-ol (0.05 mmol, see Ex. 46 below which was prepared according to Example 3 above) in THF (1 mL) at 0° C. was treated with triphenyl phosphine (26 mg, 0.1 mmol) and diisopropyl azodicarboxylate (20 uL, 0.1 mmol). After 30 min at 0° C., the reaction was allowed to warm to room temperature and was stirred for an additional 14 hours. The reaction mixture was diluted with water and concentrated in vacuo. The aqueous phase was extracted with ethyl acetate, and the organic extract was washed with brine, dried over magnesium sulfate, and concentrated in vacuo. The residue was purified using preparative HPLC (C18, H2O:MeCN gradient) to afford 2-furan-2-yl-6-(3-phenoxy-prop-1-ynyl)-[1,2,4]triazolo[1,5-a]pyrazin-8-ylamine as a white powder. 1H NMR (300 MHz, DMSO-d6) δ 8.45 (s, 1H), 7.92 (d, 1H), 7.34 (br m, 2H), 7.34 (t, J=8.7 Hz, 2H) 7.14 (d, J=3 Hz, 1H), 7.0-7.1 (br m, 3H), 6.72 (dd, J=3.0, 1.8 Hz, 1H), 5.07 (s, 2H), MS: m/z 332 [M+1].
