[CH3:1][O:2][C:3]1[CH:18]=[CH:17][C:6]([CH2:7][CH:8]([C:13]([O:15]C)=[O:14])[C:9](OC)=[O:10])=[C:5]([N+:19]([O-])=O)[CH:4]=1.[H][H]>C(O)C>[CH3:1][O:2][C:3]1[CH:4]=[C:5]2[C:6]([CH2:7][CH:8]([C:13]([OH:15])=[O:14])[C:9](=[O:10])[NH:19]2)=[CH:17][CH:18]=1A solution of dimethyl (4-methoxy-2-nitrobenzyl)malonate (19 g) in ethanol (200 ml) was hydrogenated in the presence of 10% palladium-C (2.0 g) at room temperature under one atmosphere of hydrogen for 24 hr. The reaction mixture was further stirred at 80° C. for 24 hr and the catalyst was removed by filtration. The filtrate was concentrated. The residue was dissolved in the combined solvent of THF (250 ml) and methanol (250 ml) and 1 N aqueous sodium hydroxide (126 ml) was added in an ice bath. The reaction mixture was stirred at room temperature for 72 hr and concentrated. The residue was made acidic by adding 1 N aqueous hydrochloric acid and the precipitate was collected by filtration. The crude crystals were washed with acetone to obtain the titled compound (11.7 g).
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