To a solution of 0.884 g (2.590 mmol) of 6-(6-phenylhexanoyl)-4,5,6,7-tetrahydrofuro[2,3-c]pyridine-2-carboxylic acid, 0.16 g (2.59 mmol) of 2-aminoethanol, 1.08 ml (7.77 mmol) of triethylamine and 2.50 ml (25.9 mmol) of carbon tetrachloride in 50 ml of acetonitrile, 2.04 g (7.77 mmol) of triphenylphosphine was added under ice-cooling, followed by stirring at room temperature for 4 hours. The reaction mixture was poured into water and extracted with ethyl acetate 3 times. The combined organic layer was dried over anhydrous magnesium sulfate; the solvent was distilled off under reduced pressure. The resulting crude product was purified by silica gel flush column chromatography (ethyl acetate to ethyl acetate/methanol=20/1) to yield the desired product.
