{3-[3-(2-cyano-benzyl)-5-ethyl-4-oxo-4,5-dihydro-3H-imidazo[4,5-c]pyridin-2-yl]-cyclohexyl}-carbamic acid benzyl ester → 2-[2-(3-Amino-cyclohexyl)-5-ethyl-4-oxo-4,5-dihydro-imidazo[4,5-c]pyridin-3-ylmethyl]-benzonitrile

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Reaction Steps

A solution of {3-[3-(2-cyano-benzyl)-5-ethyl-4-oxo-4,5-dihydro-3H-imidazo[4,5-c]pyridin-2-yl]-cyclohexyl}-carbamic acid benzyl ester (66 mg, 0.13 mmol) in 1:3 EtOH/THF (8 mL) was hydrogenated over 10% Pd/C (70 mg, 0.065 mmol) at room temperature. After 2 h, the catalyst was removed by filtration, rinsing with MeOH, and the filtrate was concentrated in vacuo. The crude product was purified by flash chromatography, eluting with 90:10:0.5 CH2Cl2/MeOH/NH4OH to give 2-[2-(3-amino-cyclohexyl)-5-ethyl-4-oxo-4,5-dihydro-imidazo[4,5-c]pyridin-3-ylmethyl]-benzonitrile (40 mg, 82% yield). The HCl salt was prepared by treating the amine in EtOAc with ethereal HCl (0.2 mL). 1H-NMR (CDCl3): δ 7.72 (dd, 1H, J=7.6, 1.2 Hz), 7.50 (t, 1H, J=7.6 Hz), 7.39 (t, 1H, J=7.6 Hz), 7.14 (d, 1H, J=7.2 Hz), 6.93 (d, 1H, J=7.6 Hz), 6.72 (dd, 1H, J=7.6, 2.0 Hz), 6.07 (m, 2H), 4.07 (m, 2H), 2.70 (m, 2H), 1.92 (m, 1H), 1.83 (m, 2H), 1.60 (m, 4H), 1.40 (m, 2H), 1.37 (dt, 3H, J=7.2, 3.2 Hz). MS: calculated for C22H25N5O+H 376.2; found: 376.2.

Provenance & Evidence