Sodium borohydride → 6-tert-butyl-8-fluoro-2-[3-(hydroxymethyl)-4-[1-methyl-5-[(5-methyl-6,7-dihydro-4H-pyrazolo[1,5-a]pyrazin-2-yl)amino]-6-oxo-3-pyridyl]-2-pyridyl]phthalazin-1-one

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Reaction Steps

To a solution of 128e (158 mg, 0.27 mmol) in methanol/dichloromethane (5/5 mL) was added NaBH4 (31 mg, 0.82 mmol) at room temperature. After the reaction was stirred for 1 h, LCMS indicated the reaction was complete. The reaction was quenched with water (10 mL) and concentrated under reduced pressure. The residue was extracted with dichloromethane (3×20 mL). The combined organic layer was washed with brine (30 mL), dried over Na2SO4, filtered, and concentrated under reduced pressure. The residue was purified by reverse-phase prep-HPLC to afford 128 (95 mg, 60%) as a white solid. MS-ESI: [M+H]+ 585.3. 1H NMR (500 MHz, CDCl3) δ 8.66 (d, J=5.0 Hz, 1H), 8.35 (d, J=2.0 Hz, 1H), 8.00 (d, J=2.5 Hz, 1H), 7.58-7.54 (m, overlap, 4H), 7.44 (s, 1H), 5.70 (s, 1H), 4.52-4.39 (m, 2H), 4.10-4.09 (m, 3H), 3.70 (s, 3H), 3.59 (s, 2H), 2.88-2.86 (m, 2H), 2.47 (s, 3H), 1.43 (s, 9H).

Provenance & Evidence