反应详情

A mixture of Example C2 (0.203 g, 0.491 mmol), N-ethyl piperazine (0.1 mL, 0.79 mmol) and N-methylpyrrolidine (0.021 g, 0.25 mmol) in dioxane (5 mL) was heated at 80° C. for 3 h, cooled to RT, and concentrated to dryness. The residue was dissolved in DCM and stirred with sat'd NaHCO3 for ˜15 min. The aqueous layer was back-extracted with DCM (3×) and the organic phases combined, dried (Na2SO4) and concentrated to afford a light brown oil. The crude residue was purified via silica gel chromatography (MeOH/DCM) to afford a colorless oil, which was suspended in MeCN/H2O, sonicated, frozen and lypholized overnight to afford 4-ethyl-N-(4-((6-(3-pivaloylureido)pyridin-3-yl)oxy)pyridin-2-yl)piperazine-1-carboxamide as a white solid (74 mg, 32%). 1H NMR (400 MHz, DMSO-d6): δ 11.22 (s, 1H), 10.44 (s, 1H), 9.25 (s, 1H), 8.23 (d, J=2.9 Hz, 1H), 8.12 (d, J=5.7 Hz, 1H), 8.08 (d, J=9.0 Hz, 1H), 7.71 (dd, J=9.0, 2.9 Hz, 1H), 7.37 (d, J=2.4 Hz, 1H), 6.61 (dd, J=5.7, 2.4 Hz, 1H), 3.44-3.35 (m, 4H), 2.35-2.23 (m, 6H), 1.21 (s, 9H), 0.98 (t, J=7.2 Hz, 3H); MS (ESI) m/z: 470.3 (M+H+).

1. concentrationconcentrated to dryness
2. dissolutionThe residue was dissolved in DCM
3. extractionThe aqueous layer was back-extracted with DCM (3×)
4. dry with materialdried (Na2SO4)
5. concentrationconcentrated
6. customto afford a light brown oil
7. customThe crude residue was purified via silica gel chromatography (MeOH/DCM)
8. customto afford a colorless oil, which
9. customsonicated
10. temperaturefrozen
11. waitlypholized overnight