A mixture of 4-methyl-3-[(quinolin-3-yl)ethynyl]benzoic acid (0.15 g, 0.5 mmol), N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (0.15 g, 0.7 mmol) and 1-hydroxybenzotriazole (0.1 g, 0.7 mmol) in N,N-dimethylformamide (15 ml) was stirred at ambient temperature for 1 hr. 2,4,6-Trichlorobenzohydrazide (0.125 g, 0.5 mmol) was added and the mixture stirred for 12 hrs at ambient temperature. Concentration and trituration of the residue with water produced a solid which was filtered, washed with water and the crude product was purified by flash chromatography on silica gel (elution with 10% methanol in dichloromethane) to get 2,4,6-trichloro-N-[4-methyl-3-[2-(3-quinolyl)ethynyl]benzoyl]benzohydrazide as a white solid.
