[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[CH:19]=[CH:18][C:17]([N+:20]([O-])=O)=[C:16]([CH3:23])[N:15]=2)[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2].CO.[H][H]>C1COCC1.[Pd]>[C:1]([O:5][C:6]([N:8]1[CH2:13][CH2:12][N:11]([C:14]2[CH:19]=[CH:18][C:17]([NH2:20])=[C:16]([CH3:23])[N:15]=2)[CH2:10][CH2:9]1)=[O:7])([CH3:4])([CH3:3])[CH3:2]Mix a slurry of 4-(6-methyl-5-nitro-pyridin-2-yl)-piperazine-1-carboxylic acid tert-butyl ester (46.00 g, 142.7 mmol) in THF (750 mL) at room temperature with Pd/C (5% Aldrich, 3.04 g, 1.43 mmol) then place under a hydrogen atmosphere (Parr shaker, 40-45 psi) for 6 hours. Add MeOH (250 mL), and subject the slurry to an atmosphere of hydrogen for 4 hours at room temperature. Add additional catalyst (3.04 g), then place the mixture under hydrogen for 7 hours. Filter the mixture through a pad of Celite 521®, washing with THF and MeOH then concentrate under reduced pressure to provide the title compound a pale pink solid. (41.58 g, 99% yield, MS(ES+): m/z=293 [M+H]).
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