Combined 6-(4-(4-cyano-2-methylphenyl)-5-hydroxy-1H-pyrazol-1-yl)nicotinic acid (27 mg, 0.084 mmol) and 2-oxa-6-azaspiro[3.3]heptane (12.53 mg, 0.126 mmol) in acetonitrile (1 mL) and DMF (0.5 mL). Then triethylamine (0.035 mL, 0.253 mmol) and 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (19.39 mg, 0.101 mmol) were added and the reaction was stirred at room temperature overnight. A few drops of 1N NaOH solution were added to give a clear solution, and then the mixture was diluted in ACN and purified by HPLC (Waters SunFire C18, 5 μm, ID 30×75 mm, 35-65% ACN/water+0.05% TFA) to give the title compound (3.6 mg, 10.64% yield) as a white solid. 1H NMR (400 MHz, DMSO-d6) δ ppm 2.43 (s, 3 H) 4.23-4.30 (m, 2 H) 4.53-4.60 (m, 2 H) 4.65-4.74 (m, 3 H) 7.61-7.88 (m, 4 H) 8.24 (br. s., 2 H) 8.49-8.78 (m, 2 H) 13.27 (br. s., 2 H). MS m/z [M+H]+ 402.1.
