To a solution of 4-[3-(4-phenoxy-2-propyl phenoxy)propoxy]benzenesulfonamide (0.045 g, 0.102 mmol) and acetone (3 mL) was added potassium carbonate (0.028 g, 0.204 mmol). To the resulting suspension was added cyclohexyl isocyanate (0.026 mL, 0.204 mmol) dropwise. The reaction suspension was then stirred in a 65° C. oil bath for 6 h. After cooling to room temperature, the reaction was concentrated to a residue. The residue was partitioned between ethyl acetate and water. The ethyl acetate phase was dried over sodium sulfate, filtered, and concentrated to an oil. The oil was chromatographed over silica gel with hexanes/ethyl acetate (4:1) and hexanes/ethyl acetate (3:1) to obtain the title compound.
