To a stirred solution of [(5-phenyl-isoxazole-3-carbonyl)-amino]-acetic acid (0.075 g, 0.00027 mol) in DMF (2 mL) was added DIPEA (0.171 g, 0.00132 mol), HOBt (0.0448 g, 0.00033 mol) and EDCI.HCl (0.064 g, 0.00033 mol) at ambient temperature. After 2 minutes piperidin-4-yl-(2-chloro-phenyl)-amine dihydrochloride (0.066 g, 0.00027 mol) was added and the resulting mixture was stirred overnight. The reaction mixture was then diluted with cold water and the product was extracted with ethyl acetate. The ethyl acetate layer was washed with brine solution, dried over sodium sulfate and concentrated under reduced pressure. The resulting residue was purified by column chromatography using basic aluminium oxide (25% ethyl acetate in hexane) to afford 0.066 g (57%) of 5-phenyl-isoxazole-3-carboxylic acid {2-[4-(2-chloro-phenylamino)-piperidin-1-yl]-2-oxo-ethyl}-amide. LCMS: 439.15 (M+1)+, 97.26%, 1H NMR (DMSO-d6): δ 8.62 (t, 1H), 7.95 (m, 2H), 7.55 (m, 3H), 7.4 (s, 1H), 7.25 (dd, 1H), 7.2 (m, 2H), 6.85 (d, 1H), 6.6 (t, 1H), 4.9 (d, 1H), 4.4 (d, 1H), 4.2 (d, 2H), 3.9 (d, 1H), 3.7 (m, 1H), 3.2 (m, 1H), 2.8 (m, 2H), 1.95 (t, 2H), 1.4 (m, 2H).
