To a solution of 2-[(3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-yl)carbonylbenzoic acid (100 mg, 033 mmol) in N,N-dimethylformamide (2.00 mL) was added N-methylmorpholine (0.14 mL 1.32 mmol) followed by addition of HOAt (55 mg, 0.40 mmol) and HATU (130 mg, 0.33 mmol). The mixture was stirred for 30 minutes at room temperature followed by the addition of benzylamine (36 uL, 0.33 mmol). The reaction mixture was then heated to 60° C. for 18 h. The mixture was cooled to room temperature and the solvent was evaporated. The residue was dissolved in ethyl acetate the organic layer was washed with brine, 1.0 M aq. hydrochloric acid, brine, saturated aq. sodium-hydrogencarbonate and brine. The organic layer was separated dried over anhydrous sodium sulfate, filtered and the filtrate concentrated in vacuo. The residue was purified by column chromatography (SiO2, hexanes/ethyl acetate) to afford the title compound (0.27 g, 80%). MS (EI) for C23H18N2O4: 387 (M+H).
