To a mixture of 5-(isobutyl(methyl)carbamoyl)-4′-methylbiphenyl-3-carboxylic acid (21 mg, 0.064 mmol), N-(3-dimethylaminopropyl)-N-ethylcarbodiimide hydrochloride (25 mg, 0.13 mmol), 1-hydroxybenzotriazole hydrate (9.9 mg, 0.064 mmol), and CH2Cl2 (3 mL) were added 2-chloro-5-aminomethylpyridine (14 mg, 0.097 mmol) and N,N-diisopropylethylamine (17 μL, 0.097 mmol). The mixture was stirred at room temperature overnight, and then concentrated in vacuo. The residue was purified by preparative HPLC (100×21.2 mm C18 column, 40-80% MeCN/water[10 mM Et2NH]) to yield a white foam.
