To a solution of 7-(3,5-dimethyl-4-isoxazolyl)-N4-(phenylmethyl)-3,4-quinolinediamine (for aq preparation see Intermediate 28, 0.2 g, 0.52 mmol) in DCM (10 ml) were added HOBT (0.081 g, 0.62 mmol), EDCI (0.118 g, 0.62 mmol), Et3N (0.062 g, 0.62 mmol) and formic acid (0.025 g, 0.52 mmol). The reaction mixture was stirred at room temperature overnight, then poured into water and extracted with DCM. The organic phase was washed with water, dried over Na2SO4 and concentrated. The crude solid was re-crystallized from EtOAc to give the title compound as off-white crystals (0.1 g, 48%). M.p: 216° C. 1H NMR (300 MHz, CDCl3, ppm) δ: 9.36 (s, 1H), 8.06 (s, 1H), 8.01 (s, 1H), 7.73 (d, J=7.2 Hz, 1H), 7.56 (dd, J=8.1, 8.1 Hz, 1H), 7.34 (dd, J=7.7, 7.7 Hz, 1H), 7.15-7.06 (m, 2H), 2.36 (s, 3H), 2.23 (s, 3H), 1.07 (s, 9H). LC-HRMS: ES+ exact mass calculated for C25H24N4O: 397.2028 MH+, found: 397.2021, Rt 3.03 min.
