5-[5-(3,4-Dichlorobenzoylamino)pyridin-2-yloxy]-1H-indole-2-carboxylic acid (0.250 g, 0.565 mmol) was dissolved in THF (20 mL). To the solution were added 1-benzo[1,3]dioxol-5-ylmethylpiperadine (0.125 g, 0.565 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.119 g, 0.622 mmol), and the resulting solution was stirred for 15 hours at room temperature. Water (50 mL) was added to the reaction solution, and the mixture was extracted with ethyl acetate (40 mL). After the organic layer was washed with brine, then dried over anhydrous sodium sulfate, the solvent was evaporated. The obtained residue was purified by silica gel column chromatography (CH2Cl2:MeOH=30:1) to yield 0.360 g of the title compound as a pale yellow powder.
