Methyl iodide → 1-(((5S,7S)-3-(5-(2-methoxypropan-2-yl)pyrazin-2-yl)-7-methyl-2-oxo-1-oxa-3-azaspiro[4.5]decan-7-yl)methyl)-1H-benzo[d]imidazole-6-carbonitrile

To a solution of 1-(((5S,7S)-3-(5-(2-hydroxypropan-2-yl)pyrazin-2-yl)-7-methyl-2-oxo-1-oxa-3-azaspiro[4.5]decan-7-yl)methyl)-1H-benzo[d]imidazole-6-carbonitrile (75 mg, 0.163 mmol) in N,N-Dimethylformamide (DMF) (1 mL) was added sodium hydride (9.77 mg, 0.244 mmol) at RT. After 10 minutes, MeI (0.020 mL, 0.326 mmol) was added. The mixture stirred for an hour and was purified by reverse phase HPLC (Waters Sunfire 30×150 mm Acetonitrile:Water 0.1% TFA 30-70%, 50 mL/min, 15 min). The product was free based with PL-HCO3 resin SPE to yield 1-(((5S,7S)-3-(5-(2-methoxypropan-2-yl)pyrazin-2-yl)-7-methyl-2-oxo-1-oxa-3-azaspiro[4.5]decan-7-yl)methyl)-1H-benzo[d]imidazole-6-carbonitrile as a white powder (45 mg, 58%). 1H NMR (400 MHz, DMSO-d6) δ 9.25 (d, J=1.51 Hz, 1H), 8.47-8.53 (m, 2H), 8.39 (d, J=1.00 Hz, 1H), 7.84 (d, J=8.78 Hz, 1H), 7.60 (dd, J=8.53, 1.51 Hz, 1H), 4.17 (s, 2H), 3.88 (dd, J=23.09, 10.29 Hz, 2H), 3.09 (s, 3H), 2.00 (d, J=14.05 Hz, 1H), 1.89 (d, J=14.56 Hz, 1H), 1.59-1.78 (m, 3H), 1.30-1.56 (m, 9H), 1.08 (s, 3H). MS (m/z) 443.2 (M-OMe).