Synthesis of 6-Nitroderivatives of Oxazolo[3,2-a]-pyridines and Their Reactions with Nucleophiles
نویسندگان
چکیده
5-Nitro-2-pyridone can be selectively N-phenacylated, and the resulting phenacylpyridones I undergo cyclization to 6-nitrooxazolo[3,2-a]pyridinium salts II. These salts II readily react with ammonia and aliphatic amines leading to the products of pyridine ring opening previously unknown 1-amino-2-nitro-4-(oxazole-2-yl)butadienes-1,3. Reaction of salts II with water lead to hydrolytic cleavage of the oxazole fragment.
منابع مشابه
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