4-((3R,4R)-3-Hydroxy-4-methylcyclohexylamino)-2-(1-methylcyclopropylamino)pyrimidine-5-carbonitrile (0.181 g, 0.601 mmol) was dissolved in DMSO (6 mL). Ten drops of 50% aqueous sodium hydroxide (0.047 mL, 0.901 mmol) and ten drops of 30% aqueous hydrogen peroxide were added at room temperature. The reaction mixture was stirred at 50° C. for 1 h. Upon completion of reaction, as indicated by LCMS and TLC, the reaction mixture was cooled to room temperature and was poured into 300 mL of the ice water. The aqueous layer was extracted with 20% iPrOH/chloroform (×3) and the combined organic layers were dried over anhydrous magnesium sulfate and concentrated. The crude mixture was purified by reverse-phased semi-preparative HPLC (0-50% acetonitrile+0.1% TFA in water+0.1% TFA, over 30 min). Fractions containing product were concentrated under reduced pressure. The resulting residue was redissolved in methanol (5 mL), passed over Varian StratoSpheres HCO3 resin SPE tubes for TFA removal (0.9 mmol bicarbonate equiv. per tube), and then concentrated under reduced pressure to afford 4-((1R,3R,4R)-3-hydroxy-4-methylcyclohexylamino)-2-(1-methylcyclopropylamino)pyrimidine-5-carboxamide (0.069 g, 36% yield); 1H NMR (400 MHz, DMSO-d6) δ ppm 8.79-8.92 (m, 1H), 8.28-8.39 (m, 1H), 7.32-7.48 (m, 1H), 4.56 (s, 1H), 3.83-3.97 (m, 1H), 2.89-3.08 (m, 1H), 2.18-2.31 (m, 1H), 1.97-2.08 (m, 1H), 1.61-1.74 (m, 1H), 1.35 (s, 4H), 1.05-1.26 (m, 1H), 0.94 (d, J=6.64 Hz, 5H), 0.66 (s, 3H), 0.54 (br. s., 3H); MS (ESI) m/z 320.2 [M+1]+.
