[NH2:1][C:2]1[C:7]([N+:8]([O-])=O)=[CH:6][C:5]([Br:11])=[CH:4][N:3]=1.O.O.[Sn](Cl)Cl.[BH4-].[Na+].C(OCC)(=O)C>CC(O)(C)C>[Br:11][C:5]1[CH:6]=[C:7]([NH2:8])[C:2]([NH2:1])=[N:3][CH:4]=1A procedure similar to that described in Preparation 42 was repeated, except that 12.0 g of 2-amino-5-bromo-3-nitropyridine (prepared as described in Preparation 56), 62.1 g of tin(II) chloride dihydrate, 1.04 g of sodium borohydride and 300 ml of a 9:1 by volume mixture of ethyl acetate and 2-methyl-2-propanol were used, to give the title compound as a crude product. This crude product was crystallized by trituration with a mixture of ethyl acetate and hexane, to give 7.46 g of the title compound, melting at 135°-137° C.
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