[NH2:1][C:2]1[C:3]([C:9]([O:11]C)=O)=[N:4][C:5]([Br:8])=[CH:6][N:7]=1.O.[NH2:14][NH2:15]>C(O)C>[NH2:1][C:2]1[C:3]([C:9]([NH:14][NH2:15])=[O:11])=[N:4][C:5]([Br:8])=[CH:6][N:7]=1To a suspension of methyl 3-amino-6-bromo-pyrazine-2-carboxylate (2.5 g, 10.8 mmol) in ethanol (50 mL) was added hydrazine hydrate (3.2 g, 3 mL, 64.6 mmol) and the reaction mixture heated at 70° C. for 1.5 hours forming a thick yellow solid. The reaction mixture was filtered and the solid washed with water (20 mL) and ethanol (40 mL). The solid was dried in vacuo to yield 3-amino-6-bromo-pyrazine-2-carbohydrazide (2.7 g, 94% yield) as a light yellow solid. 1H NMR (400 MHz, DMSO-d6) δ 4.53 (d, J=3.5 Hz, 2H), 7.62 (s, 2H), 8.31 (s, 1H) and 9.78 (s, 1H) ppm; LC/MS m/z 233.1 [M+H]+
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