A mixture of methyl (4S,5R)-5-(3,4-dibenzyloxyphenyl)-2-phenyl-2-oxazoline-4-carboxylate (494 mg, 1.00 mmol), 5%-palladium-carbon (64 mg) and isopropanol (5 g) was reduced with hydrogen at room temperature under atmospheric pressure for 15 hours. The reaction mixture was filtered and then the filtrate was concentrated under reduced pressure. The residue was treated with silica gel chromatography to obtain 263 mg (0.84 mmol, yield: 84%) of methyl (4S,5R)-5-(3, 4-dihydroxyphenyl)-2-phenyl-2-oxazoline-4-carboxylate.
