To a solution of 4-cyano-1H-imidazole-2-carboxylic acid [2-cyclohex-1-enyl-4-(2-hydroxy-1-hydroxymethyl-ethyl)-phenyl]-amide (as prepared in the previous step, 5.4 mg, 0.015 mmol) and pyridine (3.0 μL, 0.037 mmol) in 0.5 mL of THF at −78° C. was added a solution of triphosgene (1.8 mg, 0.0061 mmol) in 0.5 mL of DCM. The resulting mixture was warmed to RT and continued to stir for 1 h under Ar. Removal of the solvent under reduced pressure followed by flash chromatography of the residue on silica gel (1-2% MeOH-DCM) gave 2.8 mg (48%) of the title compound as a white solid: 1H-NMR (CD3OD; 400 MHz): δ 8.01 (s, 1H), 7.66 (dd, 1H, J=8.6, 2.3 Hz), 7.59 (d, 1H, J=2.3 Hz), 7.29 (d, 1H, J=8.6 Hz), 5.66 (m, 1H), 4.65 (dd, 2H, J=10.9, 10.9 Hz), 4.45 (dd, 2H, J=10.9, 4.9 Hz), 3.72 (m, 1H), 2.24 (m, 4H), 1.70-1.88 (m, 4H). Mass spectrum (ESI, m/z): Calcd. for C21H20N4O4, 393.2 (M+H). found 393.1.
