N[C:2]1[N:11]=[CH:10][C:9]2[C:4](=[C:5]([CH:14]3[CH2:18][CH2:17][CH2:16][CH2:15]3)[C:6]([O:12][CH3:13])=[CH:7][CH:8]=2)[N:3]=1.N([O-])=[O:20].[Na+].N>F[B-](F)(F)F.[H+]>[CH:14]1([C:5]2[C:6]([O:12][CH3:13])=[CH:7][CH:8]=[C:9]3[C:4]=2[NH:3][C:2](=[O:20])[N:11]=[CH:10]3)[CH2:18][CH2:17][CH2:16][CH2:15]1To a solution of 2-amino-8-cyclopentyl-7-methoxyquinazoline (1.38 g,) in tetrafluoroboric acid (30 mL), sodium nitrite solution (1.16 g in 10 mL of water) was added dropwise at 0° C. The reaction mixture was stirred at 0° C. for 1 hour and at room temperature for 18 hours. The reaction mixture was cooled in a ice bath and neutralized with 30% ammonia solution. The product was extracted with ethyl acetate (3×50 mL), combined organic extract was washed with brine and dried over anhydrous sodium sulfate. The solvent was removed under reduced pressure to give the title compound as a orange solid (1.0 g, 73%). mp 201–204° C.; 1H NMR (CDCl3): δ 1.7–2.0 (complex, 8H, 4×CH2), 3.43 (m, 1H, CH), 3.96 (s, 3H, OCH3), 6.89 (d, 1H, Ar-H, J=8.8 Hz), 7.59 (d, 1H, Ar-H, J=8.8 Hz), 8.92 (brs, 1H, NH), 9.03 (s, 1H, Ar-H).
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