A solution of 130 mg (0.237 mmol) of 4-cyano-1-(2-trimethylsilanyl-ethoxymethyl)-1H-imidazole-2-carboxylic acid[2-cyclohex-1-enyl-4-(1-methyl-2,6-dioxo-piperidin-4-yl)-phenyl]-amide (as prepared in the previous step) in CH2Cl2 (10 mL) was treated with MeOH (200 μL) and TFA (3 mL) at RT for 1.25 h. MeOH (30 mL) was added, the mixture was concentrated to half volume, MeOH (20 mL) was added, and the solvents were removed completely in vacuo at <35° C. Silica gel chromatography of the residue on a 50-g Varian MegaBond Elut SPE column with 25-50% EtOAc-hexane and by RP-HPLC (C18) with 10-80% CH3CN in 0.1% TFA/H2O over 30 min afforded 8.0 mg (8%) of the title compound as a white solid: 1H-NMR (CD3OD; 400 MHz): δ 8.19 (d, 1H, J=8.4 Hz), 8.03 (s, 1H), 7.24 (dd, 1H, J=8.4, 2.4 Hz), 7.16 (d, 1H, J=2.4 Hz), 5.87-5.82 (m, 1H), 3.47-3.37 (m, 1H), 3.16 (s, 3H), 2.96-2.91 (m, 4H), 2.33-2.25 (m, 4H), 1.92-1.77 (m, 4H). Mass spectrum (ESI, m/z): Calcd. for C23H23N5O3, 418.2 (M+H), found 418.1.
