Methanol → 3-[7-(benzyloxy)-1,1-dioxido-4H-1,2,4-benzothiadiazin-3-yl]-1-(cyclobutylamino)-4-hydroxyquinolin-2(1H)-one

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Reaction Conditions

Reaction Steps

The product of Example 304G (0.178 g, 0.35 mmol) in tetrahydrofuran (3 mL) at 0° C. was treated with methanol (0.025 mL, 0.70 mmol), followed by dropwise addition of a 2.0 M solution of lithium borohydride in tetrahydrofuran (0.260 mL, 0.52 mmol), stirred at 25° C. for one hour, and diluted with 1 N HCl. The resulting precipitate was filtered and dried. The solid was dissolved in tetrahydrofuran and absorbed onto silica gel by evaporating to dryness. The resulting silica was loaded onto a 2 g Alltech sep pack and eluted with dichloromethane to give the title compound (0.059 g, 33%). MS (ESI−) m/z 515 (M−H)−. 1H NMR (300 MHz, DMSO-d6) δ ppm 1.55 (m, 1 H) 1.71 (m, 1 H) 2.04 (m, 4 H) 3.77 (m, 1 H) 5.26 (s, 2 H) 6.57 (d, J=5.15 Hz, 1 H) 7.45 (m, 8 H) 7.64 (d, J=9.56 Hz, 1 H) 7.88 (m, 1 H) 8.05 (d, J=8.46 Hz, 1 H) 8.17 (m, 1 H).

Provenance & Evidence