Reaction Steps
To a solution of the ketoimidazole prepared in Example 2 above (2.1 g,5.85 mmol) in 10.5 mL of 1-propanol was added N,N-dimethylformamide dimethyl acetal (1.32 mL, 1.18 g, 9.94 mmol) and the solution was heated at 100° C. for 6 h. At this time, TLC indicated no starting material and N-methylguanidine·HCl (0.96 g, 8.77 mmol) and NaOEt (21% w/w solution, 3.50 mL, 3.05 g, 9.35 mmol) were added. After 18 hours, the solution was cooled to room temperature, diluted with 40 mL of water, 50 mL of 3N HCl and 50 mL of EtOAC. The layers were separated and the organic layer wash washed again with 20 mL of 3N HCl. The combined aqueous layers were basified with solid K2CO3 until bubbling ceased. The aqueous layer was extracted with EtOAc (2×50 mL). The combined organics were washed with 3×100 mL of water, concentrated and the residue was recrystallized from EtOAc to give 1.24 g (50%) of the title compound: mp=205-206° C.; IR (KBr) 3242, 3110, 1695, 1588, 1568, 1532, 1507 cm-1 ; 1H NMR (CDCl3) δ8.15 (1H, d, J=5.0 Hz), 7.71 (1H, s), 7.44 (2H, m), 6.97 (2H, t, J=8.7 Hz), 6.40 (1H, d, J=5.0 Hz), 5.18 (1H, m), 4.83 (1H, m), 4.34 (2H, m),4.15 (2H, q, J=7.1 Hz), 3.02 (3H, d, J=5.0 Hz), 2.81 (2H, m), 2.19 (2H, m), 1.87 (2H, dq, J=4.4, 12.5 Hz), 1.27 (3H, t, J=7.1 Hz); 13C NMR (CDCl3) δ164.00, 163.03, 160.73, 158.51, 158.32, 155.31, 141.96, 135.57, 130.52, 130.07, 129.97, 125.01, 115.39, 115.11, 111.73, 61.61, 53.80, 43.42, 33.43, 28.43, 14.63; Anal. Cald for C22H25N6O2F; C, 62.2; H, 5.9; N, 19.8; Found C, 61.9, H, 6.0; N, 19.4.
