The product from Example 3, 5-(5,6-difluoro-1H-indol-2-yl)-2-methoxy-phenylamine, (0.274 g, 1.0 mmol) was mixed with 4-carboxyphenyl isothiocyanate (0.183 g, 1.0 mmol) in tetrahydrofuran (10 mL) and was heated briefly to 50° C. and then allowed to stand overnight at room temperature. The tetrahydrofuran was boiled off on the rotary evaporator (no vacuum) to give a solid. Ethyl acetate (5 mL) was added, and the mixture was allowed to stand overnight at room temperature. The insoluble material was collected by filtration and was a mixture. All material from the reaction mixture was taken up in tetrahydrofuran/ethyl acetate and more 4-carboxyphenyl isothiocyanate (0.020 g, 0.11 mmol) was added and the solvent was boiled off on the rotary evaporator. Ethyl acetate was added to the solid and the mixture allowed to stand overnight at room temperature. The insoluble material was collected by filtration (0.191 g), mp 201-203° C.
