[CH2:1]([O:3][C:4]1[N:12]=[CH:11][C:10]([N+:13]([O-])=O)=[CH:9][C:5]=1[C:6]([OH:8])=[O:7])[CH3:2].O.C([O-])(O)=O.[Na+]>CCO.[Pd]>[NH2:13][C:10]1[CH:11]=[N:12][C:4]([O:3][CH2:1][CH3:2])=[C:5]([CH:9]=1)[C:6]([OH:8])=[O:7]A solution of 2-ethoxy-5-nitronicotinic acid (12.0 g, 56.6 mmol, prepared by the method described in WO9954333) in a mixture of EtOH (150 ml), H2O (150 ml), NaHCO3 (4.80 g, 57.0 mmol) and 10% palladium on carbon (1.0 g) was hydrogenated at 60 psi and at 60° C. for 6 h. The mixture was cooled, filtered and acidified with AcOH. The mixture was concentrated in vacuo and the residue triturated with DCM/MeOH (95:5) to afford the title compound as a brown/purple solid (5.0 g, 27.5 mmol, 48%); mp 260-262° C.
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