A mixture of 8-amino-N-(4-chlorobenzyl)-4-hydroxy-6-(4-morpholinylmethyl)-3-quinolinecarboxamide (Preparation 3, 331 mg) and 1,1′-carbonyl diimidazole (215 mg) in DMF (2.5 mL) is heated at 80° C. for 1 h. A second portion of 1,1′-carbonyl diimidazole (167 mg) is added and heating is continued for an additional 1 h. After cooling, water (8 mL) is added and the resulting precipitate is filtered off, washed with water and dried to afford 261 mg of the title compound. Physical characteristics: M.p. 286° C. (dec); 1H NMR (300 MHz, DMSO-d6) δ2.39, 3.57, 3.62, 4.57, 7.39, 7.61, 8.88, 10.0, 12.0. Anal. Found: C, 60.37; H, 4.78; N, 12.49.
