反应详情

To a suspension of tert-butyl (2-mercapto-benzoimidazol-1-yl)-acetate (Intermediate 3-I, 53 mg, 0.2 mmol) and K2CO3 (41.4 mg, 0.4 mmol) in acetone (0.8 ml) is added 2-cyclohexylethyl bromide (28.8 mg, 22.6 μl). The reaction mixture is kept stirring at reflux for 5 h then filtered on a short plug of silica gel. The solvents are evaporated and the crude is purified by preparative HPLC yielding the title compound in 60% as a colourless oil: tR=7.39 min (LC-1), ESI-MS (pos.): m/z 321.36 [M+H]+; 1H NMR (CDCl3): δ (ppm) 0.80-0.91 (m, 2H), 1.04-1.23 (m, 3H), 1.35 (s, 9H, tBu), 1.35 (m, 1H), 1.54-1.72 (m, 6H), 1.83 (br. s, 1H), 3.32 (t, 2H, SCH2), 4.65 (s, 2H, CH2CO2), 7.07-7.17 (m, 3Harom), 7.61 (m, 1Harom).

1. temperatureat reflux for 5 h
2. filtrationthen filtered on a short plug of silica gel
3. customThe solvents are evaporated
4. customthe crude is purified by preparative HPLC