3,4-Dimethoxy-1-benzenecarbonyl isothiocyanate was prepared using commercially available 3,4-dimethoxy-1-benzenecarbonyl chloride (80 mg) as a starting compound according to the description of the literature. 4-[(6,7-Dimethoxy-4-quinazolinyl)oxy]aniline (50 mg) was dissolved in toluene (5 ml) and ethanol (1 ml) to prepare a solution. A solution of 3,4-dimethoxy-1-benzenecarbonyl isothiocyanate in ethanol (1 ml) was then added to the solution, and the mixture was stirred at room temperature for 2 hr. The reaction solution was concentrated, and the residue was purified by chromatography on silica gel using chloroform/acetone for development to give the title compound (57 mg, yield 65%).
