Diisopropylethylamine → 1-(3-(6,7-Dimethoxyquinazolin-4-yloxy)phenyl)-3-(3-isopropylisoxazol-5-yl)urea

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Reaction Steps

A stirred solution of 3-(6,7-dimethoxyquinazolin-4-yloxy)aniline from Example 113A (89 mg, 0.30 mmol), phenyl 3-isopropylisoxazol-5-ylcarbamate from the previous step (89 mg, 0.36 mmol), N,N-diisopropylethylamine (58 mg, 0.45 mmol) and 4-(dimethylamino)pyridine (1.8 mg, 0.015 mmol) in dry tetrahydrofuran (1.5 mL), was heated at 50° C. for 30 mins. After cooling to room temperature, concentration under reduced pressure gave a residue which was partitioned between water (50 mL) and dichloromethane (50 mL). The organic layer was separated, washed with brine (50 mL), dried over MgSO4 and concentrated under reduced pressure. The residue was purified by preparative HPLC (using phenylhexyl reverse phase column, eluted with gradient of solvent B=0.05% HOAC/CH3CN and solvent A=0.05% HOAc/H2O) to afford 1-(3-(6,7-dimethoxyquinazolin-4-yloxy)phenyl)-3-(3-isopropylisoxazol-5-yl)urea as a colorless solid (25 mg, 19%). 1H NMR (300 MHz, DMSO-d6) δ 10.30 (brs, 1H), 9.14 (s, 1H), 8.56 (s, 1H), 7.57 (s, 2H), 7.39-7.44 (m, 2H), 7.31 (m, 1H), 6.99 (m, 1H), 5.99 (s, 1H), 4.00 (s, 6H), 2.90 (septet, J=6 Hz, 1H), 1.19 (d, J=6 Hz, 6H); LC-MS (ESI) m/z 450 (M+H)+.

Provenance & Evidence