DIPEA (0.096 mL, 0.56 mmol) was added drop wise to 4-phenylamino-benzoic acid (47 mg, 0.22 mmol) in DMF (4 mL). EDCI (53 mg, 0.28 mmol) and HOBT (30 mg, 0.22 mmol) were added consecutively and, after 10 mins, 2-amino-1-[4-(2-trifluoromethyl-benzoyl)-piperazin-1-yl]-ethanone in its TFA salt form (80 mg, 0.19 mmol) was added. The resulting mixture was stirred at room temperature overnight. Water was then added the resulting solid filtered to afford 68 mg of crude product. Purification by column chromatography (using silica gel of mesh size of 60-120 and 80/20 EtOAc:Hexane as the eluent) afforded 45 mg (47% yield) of N-{2-Oxo-2-[4-(2-trifluoromethyl-benzoyl)-piperazin-1-yl]-ethyl}-4-phenylamino-benzamide. LC-MS purity: 96.8%. 1H-NMR (DMSO-D6): δ 8.6 (s, 1H), 8.3 (t, 1H), 7.8 (m, 5H), 7.6 (d, 1H), 7.3 (t, 2H), 7.2 (d, 2H), 7.1 (d, 2H), 6.9 (t, 1H), 4.1 (d, 2H), 3.6 (m, 4H), 3.4 (m, 2H), 3.1 (m, 2H).
