Triethylamine (0.192 mL, 1.38 mmol) was added under nitrogen to a mixture of 5-bromo-6-methoxycarbonylmethoxy-naphthalen-2-ylmethyl-ammonium; chloride (0.25 g, 0.69 mmol), prepared in the previous step, and 1-phenyl-5-propyl-1H-pyrazole-4-carbonyl chloride (0.17 g, 0.69 mmol) in 20 mL of methylene chloride at room temperature. The reaction stirred under nitrogen for 17 h. The reaction was diluted with methylene chloride, extracted two times with water, two times with 5% sodium bicarbonate, dried (MgSO4) and the solvent removed under reduced pressure to give (1-Bromo-6-{[(1-phenyl-5-propyl-1H-pyrazole-4-carbonyl)-amino]-methyl}-naphthalen-2-yloxy)-acetic acid methyl ester (0.347 g, 95%) as a white solid, mp 144-146° C.
