[N+:1]([C:4]1[CH:9]=[CH:8][N:7]=[C:6]([C:10]([OH:12])=O)[CH:5]=1)([O-:3])=[O:2].[NH2:13][CH2:14][CH2:15][NH:16][C:17](=[O:23])[O:18][C:19]([CH3:22])([CH3:21])[CH3:20]>O1CCCC1.C(N1C=CN=C1)(N1C=CN=C1)=O>[N+:1]([C:4]1[CH:9]=[CH:8][N:7]=[C:6]([C:10]([NH:13][CH2:14][CH2:15][NH:16][C:17](=[O:23])[O:18][C:19]([CH3:21])([CH3:20])[CH3:22])=[O:12])[CH:5]=1)([O-:3])=[O:2]6.0 g of 4-nitro-2-pyridinecarboxylic acid were stirred at 60° bath temperature for 4 hours in 300 ml of absolute tetrahydrofuran and 5.9 g of 1,1'-carbonyldiimidazole. Thereafter, 6.0 g of t-butyl (2-aminoethyl)carbamate were added thereto and the mixture was heated to reflux for 4 hours. The reaction mixture was concentrated under reduced pressure and thereafter partitioned between ethyl acetate and water. The combined organic phases were dried over magnesium sulfate and concentrated. The residue was crystallized from ethyl acetate, whereby there was obtained t-butyl [2-(4-nitropyridine-2-carboxamido)ethyl]carbamate as white crystals, m.p. 130°-131°.
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