To a mixture of (S)-3-{[2-(4,5-diphenyloxazol-2-yl)-2-cyclohexen-1-yl]methyl}benzoic acid (120 mg, 0.276 mmol) and 2-(2-aminoethyl)pyridine (0.040 ml, 0.331 mmol) in DMF (5 ml) was added 1-hydroxybenzotriazole (56 mg, 0.414 mmol) and 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride (106 mg, 0.552 mmol). After stirring the resulting mixture at room temperature for 2 hours, the reaction mixture was diluted with EtOAc (30 ml), washed with water, saturated sodium hydrogencarbonate solution, water and brine successively, dried over magnesium sulfate, and evaporated in vacuo. The residue was purified by silica gel column chromatography (methylene chloride:MeOH, 20:1 elution) to give (S)-N-[2-(2-pyridyl)ethyl]-3-{[2-(4,5-diphenyloxazol-2-yl)-2-cyclohexen-1-yl]methyl}benzamide (138.8 mg, 93%).
