To a solution of methyl (5-{3-[4-(aminocarbonothioyl)-2-propyl-phenoxy]-propoxy}-1H-indol-1-yl)acetate (Example 52, 500 mg, 1.14 mmol) in ethanol (35 mL), was added 1-bromo-2-butanone (739 mg, 2.27 mmol) and pyridine (0.14 mL, 135 mg, 1.70 mmol). The reaction mixture was stirred for 3 h at 70° C. The solvent was evaporated under reduced pressure and the residue was purified by silica gel chromatography (0-15% EtOAc in hexane) to give 89 mg (16%) of the title compound. 1H NMR (400 MHz, CDCl3) δ 7.75-7.70 (m, 2H), 7.18-7.12 (m, 2H), 7.05 (d, 1H) 6.95-6.85 (m, 2H), 6.80 (s, 1H), 6.48 (d, 1H), 4.85 (s, 2H), 4.25-4.20 (m, 4H), 3.75 (s, 3H), 2.85 (q, 2H), 2.70-2.60 (m, 2H), 2.40-2.30 (m, 2H), 1.75-1.60 (m, 2H), 1.35 (t, 3H), 0.95 (t, 3H).
