DIPEA (0.114 mL, 0.66 mmol) was added drop wise to (4-phenoxy-benzoylamino)-acetic acid (60 mg, 0.22 mmol) in DMF (5 mL). EDCI (106 mg, 0.55 mmol) and HOBT (35 mg, 0.27 mmol) were then added, and after 10 mins, 1-Benzyl-piperazine (46 mg, 0.27 mmol) was added. The resulting mixture was stirred at room temperature overnight. Water was added, and the resulting solid was isolated by filtration under reduced pressure to afford N-[2-(4-benzyl-piperazin-1-yl)-2-oxo-ethyl]-4-phenoxy-benzamide in 58% yield. LC-MS purity: 99%, 1H NMR (DMSO-D6): δ 8.5 (t, 1H), 7.9 (d, 2H), 7.5 (t, 2H), 7.3 (m, 7H), 7.1 (m, 4H), 4.1 (d, 2H), 3.6 (s, 2H), 3.5 (m, 4H), 2.4 (m, 4H).
