反应详情

To a mixture of 6,7-dimethoxy-4-piperidin-4-yl-quinazoline (1.86 g, 6.80 mmol), prepared essentially as described in the previous step, and (4-isopropoxy-phenyl)-carbamic acid 4-nitro-phenyl ester (2.28 g, 7.22 mmol), prepared essentially as described in Example 1a, in CH3CN (13 mL) was added DIEA (1.24 mL, 7.50 mmol). The homogeneous solution was refluxed for 4 h, allowed to cool to rt, shaken with 1 M K2CO3, and extracted with EtOAc (2×25 mL). The organic layers were combined, washed with 0.5 M NaH2PO4 (1×50 mL), 4 M NaCl (1×25 mL), dried three times (Na2SO4), and concentrated under reduced pressure to give crude title compound as a beige semisolid (3.5 g). Flash chromotography (3:4→1:2 hex/acetone) afforded the title compound as an off-white foam (2.21 g, 72%). 1H-NMR (300 MHz, CDCl3) 9.08 (s, 1H), 7.34 (s, 1H), 7.28-7.22 (m, 3H), 6.83 (m, 2H), 6.46 (br s, 1H), 4.47 (heptet, J=6.1 Hz, 1H), 4.27 (br m, 2H), 4.07 (s, 3H), 4.06 (s, 3H), 3.59 (tt, J=11.0 Hz, 3.7 Hz, 1H), 3.15 (td, J=12.8 Hz, 2.4 Hz, 2H), 2.22-2.06 (m, 2H), 2.04-1.92 (m, 2H), 1.31 (d, J=6.1 Hz, 6H). LC/MS (ESI): calcd mass 450.2, found 451.3 (MH)+. Anal. Calcd for C25H30N4O4: C, 66.65; H, 6.71; N, 12.44. Found: C, 66.41; H, 6.68; N, 12.22.

1. customprepared essentially
2. customprepared essentially
3. temperatureThe homogeneous solution was refluxed for 4 h
4. extractionextracted with EtOAc (2×25 mL)
5. washwashed with 0.5 M NaH2PO4 (1×50 mL), 4 M NaCl (1×25 mL)
6. dry with materialdried three times (Na2SO4)
7. concentrationconcentrated under reduced pressure
8. customto give crude title compound as a beige semisolid (3.5 g)