N-(1-(2-(diethylamino)ethyl)-2-(4-ethoxybenzyl)-1H-benzo[d]-imidazol-5-ylcarbamothioyl)benzamide 20 (272 mg, 0.513 mmol) was dissolved in anhydrous tetrahydrofuran (10 mL) in a small, argon purged flask fitted with an condenser and magnetic stirbar. 2M NaOH (0.513 mL, 1.026 mmol) added and the solution was heated to reflux for 6 hours and cooled to room temperature overnight. The solution was concentrated and the residue was partitioned between H2O and ethyl acetate, transferred to a separatory funnel and the organic layer collected. The aqueous layer was further extracted with ethyl acetate and the combined organic layers were washed with brine (twice), dried over magnesium sulphate, filtered and concentrated to afford an off white solid which was slurried in hot ethyl acetate to yield white solid 21 [1-(2-Diethylamino-ethyl)-2-(4-ethoxy-benzyl)-1H-benzoimidazol-5-yl]-thiourea. Yield: 110 mg (50.3%). 1H NMR (DMSO) δ: 0.80 (t, 6H, J=7.1), 1.29 (t, 3H, J=7.0), 2.41 (q, 4H, J=7.0), 2.45-2.50 (m, 2H), 3.96 (q, 2H, J=6.9), 4.12 (t, 2H, J=6.7), 4.24 (s, 2H), 6.86 (d, 2H, J=8.6), 7.09 (dd, 1H, J=8.4, 1.5), 7.16 (d, 2H, J=8.7), 7.24 (br, 1-2H), 7.40 (d, 1H, J=8.5), 7.51 (s, 1H), 9.56 (s, 1H). MS (ESI): 426 (MH+, 100%)
